Download november 2010 - australian resuscitation council research updates

NOVEMBER 2010 – AUSTRALIAN RESUSCITATION COUNCIL RESEARCH UPDATES
Please note that guideline numbers refer to the most recent draft guidelines (Nov 2010)
1. Aguila A, Funderburk M, Guler A, McNitt S, Hallinan W, Daubert J, et al., Clinical predictors of survival in patients treated with
therapeutic hypothermia following cardiac arrest. Resuscitation 2010: 81(12); 1621-6
Therapeutic hypothermia has been shown to provide neuroprotection and improved survival in patients suffering a cardiac arrest.
We report outcomes of consecutive patients receiving therapeutic hypothermia for cardiac arrest and describe predictors of short
and long-term survival. Eighty patients receiving therapeutic hypothermia between January 2005 and December 2008 were
identified and categorized as those who survived and died. Outcomes and predictors of survival were determined. Forty-five patients
(56%) survived to hospital discharge and were alive at 30 days and among survivors 41 (91%) were alive 1 year after discharge.
Survivors were younger, were more likely to present with VF, required less epinephrine during resuscitation, were more likely to
have preserved renal function, and were less likely to be taking beta-blockers and ACE inhibitors. Predictors of survival included VF
on presentation (OR 14.9, CI 2.7–83.2, p=0.002), pre-cardiac arrest aspirin use (OR 9.7, CI 1.6–61.1, p=0.02), return of spontaneous
circulation <20min (OR 9.4, CI 2.2–41.1, p=0.003), absence of coronary artery disease (OR 5.3, CI 1.1–24.7, p=0.002) and preserved
renal function. Therapeutic hypothermia is useful in the treatment of patients suffering a cardiac arrest. Several clinical factors may
aid in predicting patients who are likely to survive after a cardiac arrest.
Guideline 11.8: Therapeutic hypothermia after cardiac arrest
2. Axelsson C, Holmberg S, Karlsson T, Axelsson ÅB and Herlitz J, Passive leg raising during cardiopulmonary resuscitation in outof-hospital cardiac arrest — Does it improve circulation and outcome? Resuscitation 2010: 81(12); 1615-20
Passive leg raising (PLR), to augment the artificial circulation, was deleted from cardiopulmonary resuscitation (CPR) guidelines in
1992. Increases in end-tidal carbon dioxide (PETCO2) during CPR have been associated with increased pulmonary blood flow
reflecting cardiac output. Measurements of PETCO2 after PLR might therefore increase our understanding of its potential value in
CPR. We also observed the alteration in PETCO2 in relation to the return of spontaneous circulation (ROSC) and no ROSC. The PETCO 2
was measured, subsequent to intubation, in 126 patients suffering an out-of-hospital cardiac arrest (OHCA), during 15min or until
ROSC. Forty-four patients were selected by the study protocol to PLR 35cm; 21 patients received manual chest compressions and 23
mechanical compressions. The PLR was initiated during uninterrupted CPR, 5min from the start of PETCO 2 measurements. During
PLR, an increase in PETCO2 was found in all 44 patients within 15s (p=0.003), 45s (p=0.002) and 75s (p=0.0001). Survival to hospital
discharge was 7% among patients with PLR and 1% among those without PLR (p=0.12). Among patients experiencing ROSC (60 of
1
Australian Research Council – November 2010 Research Updates
126), we found a marked increase in PETCO2 1min before the detection of a palpable pulse. Since PLR during CPR appears to increase
PETCO2 after OHCA, larger studies are needed to evaluate its potential effects on survival. Further, the measurement of PETCO 2
could help to minimise the hands-off periods and pulse checks.
Guideline 8: Cardiopulmonary resuscitation
3. Bjelland TW, Hjertner O, Klepstad P, Kaisen K, Dale O and Haugen B, Antiplatelet effect of clopidogrel is reduced in patients
treated with therapeutic hypothermia after cardiac arrest. Resuscitation 2010: 81(12); 1627-31
The platelet inhibitor clopidogrel is administered to patients treated with therapeutic hypothermia following cardiac arrest due to
acute coronary syndromes. Interactions with proton pump inhibitors and genetics are factors with a known potential to attenuate
the platelet inhibition of clopidogrel. In patients treated with therapeutic hypothermia, reduced gastrointestinal function and
hypothermia may also reduce the effect of clopidogrel. To investigate the net platelet inhibition of clopidogrel, we have measured
the platelet reactivity index in patients treated with therapeutic hypothermia. Twenty-five Caucasian patients treated with
clopidogrel and therapeutic hypothermia were prospectively included. Therapeutic hypothermia was defined as 33–34°C and
delivered for 24h. Clopidogrel loading doses (300–600mg) were administered enterally the day of admission and followed by 75mg
daily. Blood samples were collected on day 1 (n=25) and day 3 (n=16). The samples were analysed for inhibition by clopidogrel with a
vasodilator stimulated phosphoprotein phosphorylation kit. On day 1 and day 3, platelet reactivity index was 0.77±0.09 and
0.57±0.16, respectively. The number of patients with a satisfactory antiplatelet effect (defined as platelet reactivity index <0.5) were
0 (0%) and 5 (31%), respectively. In patients treated with therapeutic hypothermia after cardiac arrest, the effect of clopidogrel on
platelets was virtually nonexistent on day 1 after administration, with some improvement on day 3.
Guideline 11.8: Therapeutic hypothermia after cardiac arrest
4. Bounes V, Romain B, Romain and Olivier D, Olivier, Sufentanil Is Not Superior to Morphine for the Treatment of Acute
Traumatic Pain in an Emergency Setting: A Randomized, Double-Blind, Out-of-Hospital Trial. Ann Emerg Med 2010: 56(5); 509-16
We determine the best intravenous opioid titration protocol by comparing morphine and sufentanil for adult patients with severe
traumatic acute pain in an out-of-hospital setting, with a physician providing care. In this double-blind randomized clinical trial,
patients were eligible for inclusion if aged 18 years or older, with acute severe pain (defined as a numeric rating scale score ≥6/10)
caused by trauma. They were assigned to receive either intravenous 0.15 μg/kg sufentanil, followed by 0.075 μg/kg every 3 minutes
or intravenous 0.15 mg/kg morphine and then 0.075 mg/kg. The primary endpoint of the study was pain relief at 15 minutes,
defined as a numeric rating scale less than or equal to 3 of 10. Secondary endpoints were time to analgesia, adverse events, and
duration of analgesia during the first 6 hours. A total of 108 patients were included, 54 in each group. At 15 minutes, 74% of the
2
Australian Research Council – November 2010 Research Updates
patients in the sufentanil group had a numeric rating scale score of 3 or lower versus 70% of those in the morphine group (Δ4%; 95%
confidence interval –13% to 21%). At 9 minutes, 65% of the patients in the sufentanil group experienced pain relief versus 46% of
those in the morphine group (Δ18%; 95% confidence interval 0.1% to 35%). The duration of analgesia was in favor of the morphine
group. Nineteen percent of patients experienced an adverse event in both groups, all mild to moderate. Intravenous morphine
titration using a loading dose of morphine followed by strictly administered lower doses at regular intervals remains the criterion
standard. Moreover, this study supports the idea that the doses studied should be considered for routine administration in severe
pain protocols.
5. Brisson P and Brisson M, Variable Application and Misapplication of Cricoid Pressure. J Trauma 2010: 69(5); 1182-4 In 1961,
Sellick described a three-finger technique of cricoid pressure used to prevent gastric regurgitation during induction of anesthesia.
The “Sellick maneuver” is now used worldwide. The authors have observed great variability in the application of cricoid pressure by
health care providers and have suspected that misapplication occurs. The objectives of this observational study were to determine
how many different techniques of cricoid pressure were being used and to identify the reasons for such variability of technique.
Methods: During a 30-month period, the authors observed 32 health care providers applying cricoid pressure at five hospitals. The
technique and the professional degree of the person performing the maneuver were recorded. We also reviewed five national
courses that provide airway management training to determine which technique of cricoid pressure was being taught. Results: Ten
different techniques of cricoid pressure were identified in 32 observations. We identified cases in which pressure was mistakenly
applied to the thyroid cartilage and sternocleidomastoid muscles. The original three-finger Sellick technique was rarely used (3 of
32). A review of five national training courses revealed that none provide specific cricoid pressure training. Conclusion: This
observational study demonstrates that there is great variability in the application of cricoid pressure, identifying 10 different
techniques in 32 observations. Misapplication does occur with possible patient harm. We suggest four possible reasons for this
variability of technique. The authors use the three-finger cricoid pressure technique as originally described by Sellick and thought
that this technique is effective, easy to teach, and safely keeps the fingers in the midline of the cricoid cartilage.
6. Brown JB, Stassen NA, Bankey PE, Sangosanya AT, Cheng JD and Gestring ML, Helicopters and the Civilian Trauma System:
National Utilization Patterns Demonstrate Improved Outcomes After Traumatic Injury. J Trauma 2010: 69(5); 1030-6
The role of helicopter transport (HT) in civilian trauma care remains controversial. The objective of this study was to compare patient
outcomes after transport from the scene of injury by HT and ground transport using a national patient sample. Methods: Patients
transported from the scene of injury by HT or ground transport in 2007 were identified using the National Trauma Databank version
3
Australian Research Council – November 2010 Research Updates
8. Injury severity, utilization of hospital resources, and outcomes were compared. Stepwise logistic regression was used to
determine whether transport modality was a predictor of survival or discharge to home after adjusting for covariates. Results: There
were 258,387 patients transported by helicopter (16%) or ground (84%). Mean Injury Severity Score was higher in HT patients (15.9
± 12.3 vs. 10.2 ± 9.5, < 0.01), as was the percentage of patients with Injury Severity Score >15 (42.6% vs. 20.8%; odds ratio [OR],
2.83; 95% confidence interval [CI], 2.76–2.89). HT patients had higher rates of intensive care unit admission (43.5% vs. 22.9%; OR,
2.58; 95% CI, 2.53–2.64) and mechanical ventilation (20.8% vs. 7.4%; OR, 3.30; 95% CI, 3.21–3.40). HT was a predictor of survival
(OR, 1.22; 95% CI, 1.17–1.27) and discharge to home (OR, 1.05; 95% CI, 1.02–1.07) after adjustment for covariates. Conclusions:
Trauma patients transported by helicopter were more severely injured, had longer transport times, and required more hospital
resources than those transported by ground. Despite this, HT patients were more likely to survive and were more likely to be
discharged home after treatment when compared with those transported by ground. Despite concerns regarding helicopter
utilization in the civilian setting, this study shows that HT has merit and impacts outcome.
7. Chan PS, Krumholz HM, Spertus JA, Jones PG, Cram P, Berg RA, et al., Automated External Defibrillators and Survival After InHospital Cardiac Arrest. JAMA 2010: 304(19); 2129-36
Automated external defibrillators (AEDs) improve survival from out-of-hospital cardiac arrests, but data on their effectiveness in
hospitalized patients are limited. Objective: To evaluate the association between AED use and survival for in-hospital cardiac arrest.
Design, Setting, and Patients: Cohort study of 11 695 hospitalized patients with cardiac arrests between January 1, 2000, and August
26, 2008, at 204 US hospitals following the introduction of AEDs on general hospital wards. Main Outcome Measure: Survival to
hospital discharge by AED use, using multivariable hierarchical regression analyses to adjust for patient factors and hospital site.
Results: Of 11 695 patients, 9616 (82.2%) had nonshockable rhythms (asystole and pulseless electrical activity) and 2079 (17.8%) had
shockable rhythms (ventricular fibrillation and pulseless ventricular tachycardia). AEDs were used in 4515 patients (38.6%). Overall,
2117 patients (18.1%) survived to hospital discharge. Within the entire study population, AED use was associated with a lower rate
of survival after in-hospital cardiac arrest compared with no AED use (16.3% vs 19.3%; adjusted rate ratio [RR], 0.85; 95% confidence
interval [CI], 0.78-0.92; P < .001). Among cardiac arrests due to nonshockable rhythms, AED use was associated with lower survival
(10.4% vs 15.4%; adjusted RR, 0.74; 95% CI, 0.65-0.83; P < .001). In contrast, for cardiac arrests due to shockable rhythms, AED use
was not associated with survival (38.4% vs 39.8%; adjusted RR, 1.00; 95% CI, 0.88-1.13; P = .99). These patterns were consistently
observed in both monitored and non-monitored hospital units where AEDs were used, after matching patients to the individual units
in each hospital where the cardiac arrest occurred, and with a propensity score analysis. Conclusion: Among hospitalized patients
with cardiac arrest, use of AEDs was not associated with improved survival.
Guideline 7: Automated external defibrillation (AED) in BLS
4
Australian Research Council – November 2010 Research Updates
8. Duchateau F-X, Pariente D, Ducarme G, Bohbot S, Belpomme V, Devaud M-L, et al., Fetal Monitoring in the Prehospital Setting.
J Emerg Med 2010: 39(5); 623-8
Prehospital emergency care providers have very little information regarding fetal perfusion adequacy in the field. Objective: This
study was conducted to evaluate the feasibility of the use of fetal monitoring in the prehospital setting. Methods: A mobile
cardiotocometer was used for all consecutive pregnant women managed by our physician-staffed Emergency Medical Services unit.
The visualization of interpretable tracings (both fetal heart rate and tocography) at the different stages of prehospital management
was evaluated. Any change in a patient's management was also recorded. Results: There were 145 patients enrolled during 119
inter-hospital transfers and 26 primary prehospital interventions. Interpretable tracings were obtained for 81% of the patients
during the initial examination. This rate decreased to 66% during handling and transfer procedures. For 17 patients (12%), the
monitoring led to a change in the patient's management. Conclusion: This study shows that cardiotocography can be easily
performed in the prehospital setting, and is usually feasible. Moreover, the study demonstrates a positive impact of fetal heart rate
monitoring on prehospital management.
9. Frank M, Schmucker U, Stengel D, Fischer L, Lange J, Grossjohann R, et al., Proper Estimation of Blood Loss on Scene of Trauma:
Tool or Tale? J Trauma 2010: 69(5); 1191-5
Background: Visually estimated amount of blood loss may influence decision making in the prehospital setting. The purpose of this
study was to determine the ability and accuracy of paramedics and emergency physicians to visually estimate a volume of external
blood loss and the influence of different vital signs. Methods: In a prospective, blinded, observational design, participants were
asked to visually estimate the amount of blood in six simulated trauma scenarios. Casualties were provided with a simulated injury,
and a certain amount of artificial blood that was poured on the casualties' clothing and on the floor. In addition, vital signs (i.e.,
blood pressure and heart rate) were given. Each two moulage patients were provided with the same injury pattern and the same
simulated blood loss. Although one patient seemed to be normovolemic, the other seemed to be hypovolemeic by the given vital
signs., Results: With regard to all given amounts of blood loss, providing vital parameters suggesting instability (i.e., low blood
pressure, high heart rate) led to a higher estimation of the lost blood volume in both paramedics and emergency physicians.
However, estimations were influenced impressively by the given parameters. For both stable and unstable patients, small actual
volumes were overestimated, whereas higher volumes tended to be underestimated. Neither occupational status (emergency
physician or paramedic) nor gender or level of experience influenced accuracy of estimated blood loss significantly.
Guideline 8.1: Principles of control of bleeding
5
Australian Research Council – November 2010 Research Updates
10. Green SM, Roback MG and Krauss B, Laryngospasm During Emergency Department Ketamine Sedation: A Case-Control Study.
Ped Emerg Care 2010: 26(11); 798-802
Objective: The objective of this study was to assess predictors of emergency department (ED) ketamine-associated laryngospasm
using case-control techniques. Methods: We performed a matched case-control analysis of a sample of 8282 ED ketamine sedations
(including 22 occurrences of laryngospasm) assembled from 32 prior published series. We sequentially studied the association of
each of 7 clinical variables with laryngospasm by assigning 4 controls to each case while matching for the remaining 6 variables. We
then used univariate statistics and conditional logistic regression to analyze the matched sets. Results: We found no statistical
association of age, dose, oropharyngeal procedure, underlying physical illness, route, or coadministered anticholinergics with
laryngospasm. Coadministered benzodiazepines showed a borderline association in the multivariate but not univariate analysis that
was considered anomalous. Conclusions: This case-control analysis of the largest available sample of ED ketamine-associated
laryngospasm did not demonstrate evidence of association with age, dose, or other clinical factors. Such laryngospasm seems to be
idiosyncratic, and accordingly, clinicians administering ketamine must be prepared for its rapid identification and management.
Given no evidence that they decrease the risk of laryngospasm, coadministered anticholinergics seem unnecessary.
11. Hirshberg A, Frykberg E, Mattox K and Stein M, Triage and Trauma Workload in Mass Casualty: A Computer Model. J Trauma
2010: 69(5); 1074-82
Background: The aim of this study was to quantitatively analyze the impact of hospital triage on the workload of trauma teams in the
Emergency Department during a mass casualty incident, using a computer model. Methods: The inflow and triage of casualties into
an Emergency Department with 5 trauma teams was modeled using the Monte Carlo method. Triage was represented as a binary
classification task performed in one or two sequential steps. The input variables were triage accuracy (specificity and sensitivity) and
casualty load, and the key output variable was the time to saturation (TTS) of the trauma teams, which was computed from the
available and needed team minutes. Results: The relationship between an increasing casualty load and the TTS describes a sigmoidshaped curve. Improving triage accuracy extends the TTS and shifts the curve to the right. Switching to sequential competent triage
(80% accuracy) results in TTS that is similar to perfect single-step triage (100% accuracy) but at the cost of investing less team time in
urgent casualties. The optimal ratio of trauma teams to urgent casualties in sequential mode is 1:8, indicating that the treatment of
urgent casualties must be delegated to reinforcement staff., Conclusions: This study introduces innovative tools for quantitative
analysis of hospital triage in mass casualty incidents and shows how triage accuracy and mode affect the ability of trauma teams to
cope with heavy casualty loads. These tools can be used to optimize the hospital response to future threats.
6
Australian Research Council – November 2010 Research Updates
12. Kirves H, Handolin L, Niemela M, Pitkaniemi J and Randell T, Paramedics' and pre-hospital physicians' assessments of
anatomic injury in trauma patients: a cohort study. Scandin J Trauma, Resusc Emerg Med 2010: 18(1); 60
BACKGROUND: The pre-hospital assessment of a blunt trauma is difficult. Common triage tools are the mechanism of injury (MOI),
vital signs, and anatomic injury (AI). Compared to the other tools, the clinical assessment of anatomic injury is more subjective than
the others, and, hence, more dependent on the skills of the personnel. The aim of the study was to estimate whether the training
and qualifications of the personnel are associated with the accuracy of prediction of anatomic injury and the completion of prehospital procedures indicated by local guidelines. METHODS: Adult trauma patients met by a trauma team at Helsinki University
Trauma Centre during a 12-month period (n=422) were retrospectively analysed. To evaluate the accuracy of prediction of anatomic
injury, clinically assessed pre-hospital injuries in six body regions were compared to injuries assessed at hospital in two patient
groups, the patients treated by pre-hospital physicians (group 1, n=230) and those treated by paramedics (group 2, n=190).RESULTS:
The groups were comparable in respect to age, sex, and MOI, but the patients treated by physicians were more severely injured than
those treated by paramedics [ISS median (interquartile range) 16 (6 -26) vs. 6 (2-10)], thus rendering direct comparison of the groups
ineligible. The positive predictive values (95 % confidence interval) of assessed injury were highest in head injury [0,91 (0,84-0,95) in
group 1 and 0,86 (0,77-0,92) in group 2]. The negative predictive values were highest in abdominal injury [0,85 (0,79-0,89) in group 1
and 0,90 (0,84-0,93) in group 2]. The measurements of agreement between injuries assessed pre- and in-hospitally were moderate
in thoracic and extremity injuries. Substantial kappa values (95 % confidence interval) were achieved in head injury, 0,67 (0,57-0,77)
in group 1 and 0,63 (0,52-0,74) in group 2. The rate of performing the pre-hospital procedures as indicated by the local instructions
was 95-99 %, except for decompression of tension pneumothorax. CONCLUSION: Accurate prediction of anatomic injury is
challenging. No conclusive differences were seen in the ability of pre-hospital physicians and paramedics to predict anatomic injury
in the respective patient populations.
13. Leonard J, Kuppermann N, Olsen C, Babcock-Cimpello L, Brown K, Mahajan P, et al., Factors Associated With Cervical Spine
Injury in Children After Blunt Trauma. Ann Emerg Med 2010: Nov 1
Cervical spine injuries in children are rare. However, immobilization and imaging for potential cervical spine injury after trauma are
common and are associated with adverse effects. Risk factors for cervical spine injury have been developed to safely limit
immobilization and radiography in adults, but not in children. The purpose of our study is to identify risk factors associated with
cervical spine injury in children after blunt trauma. We conducted a case-control study of children younger than 16 years, presenting
after blunt trauma, and who received cervical spine radiographs at 17 hospitals in the Pediatric Emergency Care Applied Research
Network (PECARN) between January 2000 and December 2004. Cases were children with cervical spine injury. We created 3 control
groups of children free of cervical spine injury: (1) random controls, (2) age and mechanism of injury-matched controls, and (3) for
7
Australian Research Council – November 2010 Research Updates
cases receiving out-of-hospital emergency medical services (EMS), age-matched controls who also received EMS care. We abstracted
data from 3 sources: PECARN hospital, referring hospital, and out-of-hospital patient records. We performed multiple logistic
regression analyses to identify predictors of cervical spine injury and calculated the model's sensitivity and specificity. We reviewed
540 records of children with cervical spine injury and 1,060, 1,012, and 702 random, mechanism of injury, and EMS controls,
respectively. In the analysis using random controls, we identified 8 factors associated with cervical spine injury: altered mental
status, focal neurologic findings, neck pain, torticollis, substantial torso injury, conditions predisposing to cervical spine injury, diving,
and high-risk motor vehicle crash. Having 1 or more factors was 98% (95% confidence interval 96% to 99%) sensitive and 26% (95%
confidence interval 23% to 29%) specific for cervical spine injury. We identified similar risk factors in the other analyses. We
identified an 8-variable model for cervical spine injury in children after blunt trauma that warrants prospective refinement and
validation.
Guideline 8.18: Management of a potential spinal injury
14. Lyon RM, Clarke S, Gowens P, Egan G and Clegg GR, Resuscitation quality assurance for out-of-hospital cardiac arrest –
Setting-up an ambulance defibrillator telemetry network. Resuscitation 2010: 81(12);1726-8
Out-of-hospital cardiac arrest (OHCA) is a leading cause of pre-hospital mortality. Chest compressions performed during
cardiopulmonary resuscitation aim to provide adequate perfusion to the vital organs during cardiac arrest. Poor resuscitation
technique and the quality of pre-hospital CPR influences outcome from OHCA. Transthoracic impedance (TTI) measurement is a
useful tool in the assessment of the quality of pre-hospital resuscitation by ambulance crews but TTI telemetry has not yet been
performed in the United Kingdom. We describe a pilot study to implement a data network to collect defibrillator TTI data via
telemetry from ambulances. Prospective, observational pilot study over a 5-month period. Modems were fitted to 40 defibrillators
on ambulances based in Edinburgh. TTI data was sent to a receiving computer after resuscitation attempts for OHCA. 58 TTI traces
were transmitted during the pilot period. Compliance with the telemetry system was high. The mean ratio of chest compressions
was 73% (95% CI 69–77%), the mean chest compression rate was 128 (95% CI 122–134). The mean time interval from chest
compression interruption to shock delivery was 27s (95% CI 22–32s). Trans-thoracic impedance analysis is an effective means of
recording important measures of resuscitation quality including the hands-on-the-chest time, compression rate and defibrillation
interval time. TTI data transmission via telemetry is straightforward, efficient and allows resuscitation data to be captured and
analysed from a large geographical area. Further research is warranted on the impact of post-resuscitation reporting on the quality
of resuscitation delivered by ambulance crews.
8
Australian Research Council – November 2010 Research Updates
15. Mahler SA, Pattani S, Standifer J, Caldito G, Conrad SA and Arnold TC, Clinical Sobriety Assessment by Emergency Physicians
in Blunt Trauma Patients with Acute Alcohol Exposure. J Emerg Med 2010: 39(5);685-90
Background: Alcohol use increases injury risk and severity. However, few studies have evaluated the ability of emergency physicians
(EPs) to accurately determine sobriety. Objectives: To determine the predictive value of clinical sobriety assessment by EPs in blunt
trauma patients with acute alcohol use. Materials and Methods: Blunt trauma patients, aged 18-65 years with suspected acute
alcohol use, were prospectively enrolled in the study. EPs assessed study subjects before sample collection for blood alcohol level
(BAL) and urine drug screen measurement. Alcohol exposure was considered significant if BAL was >= 80 mg/dL. Sobriety (nonsignificant alcohol exposure) was defined as a BAL < 80 mg/dL. EP sobriety assessment was compared to measured BAL and
predictive values were calculated. Agreement on significance of alcohol exposure occurred if EP-estimated BAL > 80 mg/dL agreed
with measured BAL > 80 mg/dL, or estimated BAL < 80 mg/dL agreed with measured BAL < 80 mg/dL. Chi-squared analysis was used
to compare the proportion of correct physician assessments among patients with sobriety and those with significant alcohol
exposure. Results: Of 158 enrolled subjects, 153 completed clinical assessment. EP assessment had a predictive value of 83% (95%
confidence interval [CI] 77-90%) for significant alcohol exposure and 69% (95% CI 60-78%) for sobriety. Agreement on the
significance of alcohol exposure was 82% (125/153; 95% CI 76-88%). EPs identified 32% (11/34; 95% CI 17-48%) of sober patients,
but identified 96% (114/119; 95% CI 92-99%) of patients with significant alcohol exposure. EP assessment was significantly less
accurate in identifying sober patients (p < 0.01). Conclusions: Emergency physicians identified significant recent alcohol exposure in
blunt trauma patients 96% of the time. However, clinical assessment by EPs in blunt trauma patients with recent alcohol use had
only moderate predictive value for significant alcohol exposure. Sober patients were frequently misidentified as having significant
alcohol exposure.
16. Mirzoyev DS, McLeod C, Bunch TJ, Bell MR and White RD, Hypokalemia during the cooling phase of therapeutic hypothermia
and its impact on arrhythmogenesis. Resuscitation 2010: 81(12);1632-6
Mild to moderate therapeutic hypothermia (TH) has been shown to improve survival and neurological outcome in patients
resuscitated from out-of-hospital cardiac arrest (OHCA) with ventricular fibrillation (VF) as the presenting rhythm. This approach
entails the management of physiological variables which fall outside the realm of conventional critical cardiac care. Management of
serum potassium fluxes remains pivotal in the avoidance of lethal ventricular arrhythmia. We retrospectively analyzed potassium
variability with TH and performed correlative analysis of QT intervals and the incidence of ventricular arrhythmia. We enrolled 94
sequential patients with OHCA, and serum potassium was followed intensively. The average initial potassium value was
3.9±0.7mmoll−1 and decreased to a nadir of 3.2±0.7mmoll−1 at 10h after initiation of cooling (p<0.001). Eleven patients developed
sustained polymorphic ventricular tachycardia (PVT) with eight of these occurring during the cooling phase. The corrected QT
9
Australian Research Council – November 2010 Research Updates
interval prolonged in relation to the development of hypothermia (p<0.001). Hypokalemia was significantly associated with the
development of PVT (p=0.002), with this arrhythmia being most likely to develop in patients with serum potassium values of less
than 2.5mmoll−1 (p=0.002). Rebound hyperkalemia did not reach concerning levels (maximum 4.26±0.8mmoll−1 at 40h) and was
not associated with the occurrence of ventricular arrhythmia. Furthermore, repletion of serum potassium did not correlate with the
development of ventricular arrhythmia. Therapeutic hypothermia is associated with a significant decline in serum potassium during
cooling. Hypothermic core temperatures do not appear to protect against ventricular arrhythmia in the context of severe
hypokalemia and cautious supplementation to maintain potassium at 3.0mmoll−1 appears to be both safe and effective.
Guideline 11.8: Therapeutic hypothermia after cardiac arrest
17. Mörtberg E, Zetterberg H, Nordmark J, Blennow K, Rosengren L and Rubertsson S, S-100B is superior to NSE, BDNF and GFAP
in predicting outcome of resuscitation from cardiac arrest with hypothermia treatment. Resuscitation 2010: In Press, Corrected
Proof(10 Nov);
Objective: To conduct a pilot study to evaluate the blood levels of brain derived neurotrophic factor (BDNF), glial fibrillary acidic
protein (GFAP), neuron specific enolase (NSE) and S-100B as prognostic markers for neurological outcome 6 months after
hypothermia treatment following resuscitation from cardiac arrest. Design Prospective observational study. Setting: One intensive
care unit at Uppsala University Hospital. Patients: Thirty-one unconscious patients resuscitated after cardiac arrest. Interventions:
None. Measurements and main results: Unconscious patients after cardiac arrest with restoration of spontaneous circulation (ROSC)
were treated with mild hypothermia to 32-34 °C for 26 h. Time from cardiac arrest to target temperature was measured. Blood
samples were collected at intervals of 1-108 h after ROSC. Neurological outcome was assessed with Glasgow-Pittsburgh cerebral
performance category (CPC) scale at discharge from intensive care and again 6 months later, when 15/31 patients were alive, of
whom 14 had a good outcome (CPC 1-2). Among the predictive biomarkers, S-100B at 24 h after ROSC was the best, predicting poor
outcome (CPC 3-5) with a sensitivity of 87% and a specificity of 100%. NSE at 96 h after ROSC predicted poor outcome, with
sensitivity of 57% and specificity of 93%. BDNF and GFAP levels did not predict outcome. The time from cardiac arrest to target
temperature was shorter for those with poor outcome. Conclusions: The blood concentration of S-100B at 24 h after ROSC is highly
predictive of outcome in patients treated with mild hypothermia after cardiac arrest.
Guideline 11.8: therapeutic hypothermia after cardiac arrest
10
Australian Research Council – November 2010 Research Updates
18. Nguyen HL, Gore JM, Saczynski JS, Yarzebski J, Reed G, Spencer FA, et al., Age and Sex Differences and 20-Year Trends (1986
to 2005) in Prehospital Delay in Patients Hospitalized With Acute Myocardial Infarction. Circulation: Cardiovascular Quality and
Outcomes 2010: Online first(19 Oct)
Background: The prompt administration of coronary reperfusion therapy for patients with an evolving acute myocardial infarction
(AMI) is crucial in reducing mortality and the risk of serious clinical complications in these patients. However, long-term trends in
extent of prehospital delay and factors affecting patient's care-seeking behavior remain relatively unexplored, especially in men and
women of different ages. The objectives of this study were to examine the overall magnitude and 20-year trends (1986 to 2005) in
duration of prehospital delay in middle-aged and elderly men and women hospitalized with AMI. Methods and Results: The study
sample consisted of 5967 residents of the Worcester, Mass, metropolitan area hospitalized at all greater Worcester medical centers
for AMI between 1986 and 2005 who had information available about duration of prehospital delay. Compared with men <65 years,
patients in other age-sex strata exhibited longer prehospital delays over the 20-year period under study. The multivariable-adjusted
medians of prehospital delay were 1.96, 2.07, and 2.57 hours for men <65 years, men 65 to 74 years, and men ≥75 years and 2.08,
2.33, and 2.27 hours for women <65 years, women 65 to 74 years, and women ≥75 years, respectively. These age and sex
differences have narrowed over time, which has been largely explained by changes in patient's comorbidity profile and AMIassociated characteristics. Conclusions: Our results suggest that duration of prehospital delay in persons with symptoms of AMI has
remained essentially unchanged during the 20-year period under study and elderly individuals are more likely to delay seeking
timely medical care than younger persons.
19. Perkins G, Woollard M, Cooke M, Deakin C, Horton J, Lall R, et al., Prehospital Randomised Assessment of a Mechanical
Compression Device In Cardiac Arrest (PaRAMeDIC) Trial Protocol. Scandin J Trauma, Resusc Emerg Med 2010: 18(1);58
BACKGROUND: Survival after out-of-hospital cardiac arrest is closely linked to the quality of CPR, but in real life, resuscitation during
pre-hospital care and ambulance transport is often suboptimal. Mechanical chest compression devices deliver consistent chest
compressions, are not prone to fatigue and could potentially overcome some of the limitations of manual chest compression.
However, there is no high-quality evidence that they improve clinical outcomes, or that they are cost effective. The Pre-hospital
Randomised Assessment of a Mechanical Compression Device In Cardiac Arrest (PARAMEDIC) trial is a pragmatic cluster randomised
study of the LUCAS-2 device in adult patients with non-traumatic out-of-hospital cardiac arrest . METHODS: The primary objective of
this trial is to evaluate the effect of chest compression using LUCAS-2 on mortality at 30 days post out-of-hospital cardiac arrest,
compared with manual chest compression. Secondary objectives of the study are to evaluate the effects of LUCAS-2 on survival to 12
months, cognitive and quality of life outcomes and cost-effectiveness. Methods: Ambulance service vehicles will be randomised to
either manual compression (control) or LUCAS arms. Adult patients in out-of-hospital cardiac arrest, attended by a trial vehicle will
11
Australian Research Council – November 2010 Research Updates
be eligible for inclusion. Patients with traumatic cardiac arrest or who are pregnant will be excluded. The trial will recruit
approximately 4000 patients from England, Wales and Scotland. A waiver of initial consent has been approved by the Research
Ethics Committees. Consent will be sought from survivors for participation in the follow-up phase. CONCLUSION: The trial will assess
the clinical and cost effectiveness of the LUCAS-2 mechanical chest compression device. Trial Registration: The trial is registered on
the International Standard Randomised Controlled Trial Number Registry (ISRCTN08233942).
Guideline 11.6: Equipment & techniques in adult ALS
20. Pichamuthu K and Jerobin J, Bioscavenger therapy for organophosphate poisoning an open-labeled pilot randomized trial
comparing fresh frozen plasma or albumin with saline in acute organophosphate poisoning in humans. Clin Toxicol 2010: 48(813-9
Traditional treatment of organophosphate poisoning (OP) with oximes has had limited success. Fresh frozen plasma (FFP) or
albumin, acting as bioscavengers to mop up free organophosphate, has been recently proposed as a treatment modality. In this pilot
open-label, three-arm, randomized controlled study exploring proof of concept, we evaluated if bioscavenger therapy had a role in
OP. Patients and methods. Sixty patients with significant poisoning presenting within 12 hours, with suppression of
pseudocholinesterase activity to < 1,000 U/L, were randomized to receive FFP (8 bags, 250 mL each over 3 days), 20% human
albumin (4 × 100 mL over 3 days), or saline (2,000 mL over 3 days) in addition to atropine and supportive care. Pseudocholinesterase
and organophosphate levels were measured pretreatment, post-infusion (Day 2, Day 3), and predischarge and expressed as mean ±
standard error. The incidence of intermediate syndrome, need for mechanical ventilation, atropine requirement, and mortality were
assessed. Results. Twenty patients received albumin and 19 patients each FFP or saline. FFP increased pseudocholinesterase levels
(250 ± 44-1,241 ± 364 U/L) significantly (p = 0.007). Small, nonsignificant increases were observed with saline (160 ± 30-259 ± 78)
and albumin (146 ± 18-220 ± 61). Organophosphate levels reduced in all 3 arms; no clear-cut trends were observed. We observed
more cases of intermediate syndrome with FFP [10/19 (53%) vs. 5/20 (25%) vs. 5/19 (26%), FFP, albumin, and saline arms (p = 0.15)].
The interventions did not affect ventilatory requirements (14/19 vs. 15/20 vs. 14/19) or prevent delayed intubation. There were no
differences in mean (±standard error) atropine requirement (in milligrams) in the first 3 days (536 ± 132 vs. 361 ± 125 vs. 789 ± 334)
and duration (in days) of ventilation (10.0 ± 2.1 vs. 7.1 ± 1.5 vs. 7.5 ± 1.5) or hospital stay (12.4 ± 2.2 vs. 9.8 ± 1.4 vs. 9.8 ± 1.6). Two
patients developed adverse effects with FFP. Mortality was similar (4/19 vs. 5/20 vs. 2/19, p = 0.6). Conclusions: Despite significant
increase in pseudocholinesterase levels with FFP, this pilot study did not demonstrate favorable trends in clinical outcomes with FFP
or albumin.
Guideline 8.12: Emergency management of a victim who has been poisoned
12
Australian Research Council – November 2010 Research Updates
21. Robinson S, Swain A, Hoyle S and Larsen P, Survival from out-of-hospital cardiac arrest in New Zealand following the 2005
resuscitation guideline changes. Resuscitation 2010: 81(12);1648-51
The effect of cardiopulmonary resuscitation guideline changes on out-of-hospital survival rates and defibrillation efficacy was
investigated. The guideline changes were those recommended by the International Liaison Committee on Resuscitation in 2005. A
retrospective comparative study was undertaken of out-of-hospital cardiac arrests in the Wellington region. The effect of guideline
changes between the periods of 1st July 2005–30th June 2006 and 1st June 2007–31st May 2008 was examined. Data was collected
from Wellington Free Ambulance and hospital records in accordance with the Utstein template. The primary outcome measure was
survival to hospital discharge. Additional end points included individual shock success, return of spontaneous circulation (ROSC) and
survival to hospital admission. There was no significant increase in survival to hospital discharge with 11% (18/162) pre-change and
12% (20/170) post-change (p=0.5). First-shock efficacy decreased from 68% (65/96) to 62% (57/92) (p=0.75). Second shock efficacy
decreased from 47% (14/30) to 27% (9/33) (p=0.12). The proportion of patients with ROSC increased from 34% (55/162) to 42%
(72/170) (p=0.07, Chi squared). The proportion surviving to hospital increased significantly from 22% (36/162) to 36% (61/170)
(p=0.006). Withdrawal of atropine in 2005 had no adverse effect on the outcome. This study suggests that in the Wellington Region
of New Zealand, the new guidelines have improved survival to hospital but not to discharge. Whilst the guideline changes have
resulted in a trend towards decreased shock success rates, ROSC and survival to hospital admission have both increased.
22. Ryynanen O-P, Iirola T, Reitala J, Palve H and Malmivaara A, Is Advanced Life Support better than Basic Life Support in
prehospital care? A systematic review. Scandin J Trauma, Resusc Emerg Med 2010: 18(1);62
BACKGROUND: Prehospital care is classified into ALS- (advanced life support) and BLS- (basic life support) levels according to the
methods used. ALS-level prehospital care uses invasive methods, such as intravenous fluids, medications and intubation. However,
the effectiveness of ALS care compared to BLS has been questionable. Aim - The aim of this systematic review is to compare the
effectiveness of ALS- and BLS-level prehospital care. MATERIAL AND METHODS: In a systematic review, articles where ALS-level
prehospital care was compared to BLS-level or any other treatment were included. The outcome variables were mortality or
patient's health-related quality of life or patient's capacity to perform daily activities. RESULTS: We identified 46 articles, mostly
retrospective observational studies. The results on the effectiveness of ALS in unselected patient cohorts are contradictory. In
cardiac arrest, early cardiopulmonary resuscitation and defibrillation are essential for survival, but prehospital ALS interventions
have not improved survival. Prehospital thrombolytic treatment reduces mortality in patients having a myocardial infarction. The
majority of research into trauma favours BLS in the case of penetrating trauma and also in cases of short distance to a hospital. In
patients with severe head injuries, ALS provided by paramedics and intubation without anaesthesia can even be harmful. If the
prehospital care is provided by an experienced physician and by a HEMS organisation (Helicopter Emergency Medical Service), ALS
13
Australian Research Council – November 2010 Research Updates
interventions may be beneficial for patients with multiple injuries and severe brain injuries. However, the results are contradictory.
CONCLUSIONS: ALS seems to improve survival in patients with myocardial infarction and BLS seems to be the proper level of care for
patients with penetrating injuries. Some studies indicate a beneficial effect of ALS among patients with blunt head injuries or
multiple injuries. There is also some evidence in favour of ALS among patients with epileptic seizures as well as those with a
respiratory distress.
23. Scheuermeyer F, Christenson J, Innes G, Boychuk B, Yu E and Grafstein E, Safety of Assessment of Patients With Potential
Ischemic Chest Pain in an Emergency Department Waiting Room: A Prospective Comparative Cohort Study. Ann Emerg Med 2010:
56(5);455-62
Emergency department (ED) crowding has been associated with a variety of adverse outcomes. Current guidelines suggest that
patients with potentially ischemic chest pain should undergo rapid assessment and treatment in a monitored setting to optimize the
diagnosis of acute coronary syndrome. These patients may be at high risk of incorrect diagnosis and adverse events when their
evaluation is delayed because of crowding. To mitigate crowding-related delays, we developed processes that enabled emergency
physicians to evaluate potentially sick patients in the waiting room when all nurse-staffed stretchers are occupied. The objective of
this study was to investigate the safety of waiting room chest pain evaluation. This prospective comparative cohort study was
conducted in a busy urban, tertiary care ED. Explicit triage and waiting room evaluation processes were introduced. One thousand
one hundred seven patients with chest pain of potential cardiac origin were triaged either to a monitored bed or a waiting room
chair, depending on bed availability and triage judgment. After diagnostic evaluation, patients were followed for 30 days to identify
the proportion of missed cases of acute coronary syndrome (primary outcome) and other prespecified adverse events. Analysis was
based on intention to treat. Eight hundred four patients were triaged to monitored bed and 303 to waiting room evaluation. Initial
vital signs were similar, but the waiting room group was younger and had lower rates of some cardiovascular risk factors. The rate of
acute coronary syndrome, defined as acute myocardial infarction or objective unstable angina, was 11.7% in the monitored bed
group and 7.6% in waiting room patients. There were no missed acute coronary syndrome cases in either the monitored bed group
(0%; 95% confidence interval [CI] 0% to 0.4%) or the waiting room group (0%; 95% CI 0% to 1.0%). There were 32 adverse events in
the monitored bed group (4.0%; 95% CI 2.6% to 5.3%) and 2 in the waiting room group (0.7%; 95% CI 0% to 1.6%). Our organized
approach to triage and waiting room evaluation for stable chest pain patients was safe and efficient. Although waiting room
evaluation is not ideal, it may be a feasible contingency strategy for periods when ED crowding compromises access to monitored,
nurse-staffed ED beds.
14
Australian Research Council – November 2010 Research Updates
24. Serrano L, Hess E, Bellolio M, Murad M, Montori V, Erwin P, et al., Accuracy and Quality of Clinical Decision Rules for Syncope
in the Emergency Department: A Systematic Review and Meta-analysis. Ann Emerg Med 2010: 56(4);362-73
We assess the methodological quality and prognostic accuracy of clinical decision rules in emergency department (ED) syncope
patients. We searched 6 electronic databases, reviewed reference lists of included studies, and contacted content experts to identify
articles for review. Studies that derived or validated clinical decision rules in ED syncope patients were included. Two reviewers
independently screened records for relevance, selected studies for inclusion, assessed study quality, and abstracted data. Randomeffects meta-analysis was used to pool diagnostic performance estimates across studies that derived or validated the same clinical
decision rule. Between-study heterogeneity was assessed with the I2 statistic, and subgroup hypotheses were tested with a test of
interaction. We identified 18 eligible studies. Deficiencies in outcome (blinding) and interrater reliability assessment were the most
common methodological weaknesses. Meta-analysis of the San Francisco Syncope Rule (sensitivity 86% [95% confidence interval {CI}
83% to 89%]; specificity 49% [95% CI 48% to 51%]) and the Osservatorio Epidemiologico sulla Sincope nel Lazio risk score (sensitivity
95% [95% CI 88% to 98%]; specificity 31% [95% CI 29% to 34%]). Subgroup analysis identified study design (prospective, diagnostic
odds ratio 8.82 [95% CI 3.5 to 22] versus retrospective, diagnostic odds ratio 2.45 [95% CI 0.96 to 6.21]) and ECG determination (by
evaluating physician, diagnostic odds ratio 25.5 [95% CI 4.41 to 148] versus researcher or cardiologist, diagnostic odds ratio 4 [95%
CI 2.15 to 7.55]) as potential explanations for the variability in San Francisco Syncope Rule performance. The methodological quality
and prognostic accuracy of clinical decision rules for syncope are limited. Differences in study design and ECG interpretation may
account for the variable prognostic performance of the San Francisco Syncope Rule when validated in different practice settings.
Guideline 8.21: Syncope
25. Shahin H, Gopinath SP and Robertson CS, Influence of Alcohol on Early Glasgow Coma Scale in Head-Injured Patients. J
Trauma 2010: 69(5);1176-81
Background: To assess the depressant effects of alcohol on the level of consciousness of patients admitted with head injuries, this
study examined the changes that occur in the Glasgow Coma Scale (GCS) of traumatic brain injury patients over time. Methods: The
records of 269 head trauma patients consecutively admitted to the neurosurgery intensive care unit were examined retrospectively.
Eighty-one patients were excluded because of incomplete data. The remaining 188 patients were further divided into an intoxicated
group (blood alcohol concentration [BAC] ≥0.08%, n = 100 [53%]) and a nonintoxicated group (BAC <0.08%, n = 88 [47%]). The GCS in
the prehospital setting, in the emergency department, and the highest GCS achieved during the first 24 hours postinjury were
compared. Results: The change between emergency department-GCS and the best day 1 GCS in the intoxicated group was greater
than the nonintoxicated group and deemed clinically and statistically significant; median change (3 vs. 0) < 0.001. To assess whether
these results were directly related to the BAC%, piecewise regression using a general linear model was used to assess the intercept
15
Australian Research Council – November 2010 Research Updates
and slope of alcohol on the changes of GCS with cutting point at BAC% = 0.08. The analysis showed that, in the nonintoxicated range,
the effect of alcohol was not significantly related to the changes of GCS. But in the intoxicated range, BAC% was significantly
positively related to the changes of GCS. Conclusion: This study concludes that the GCS increases significantly over time in alcohol
intoxicated patients with traumatic brain injury.
26. Teodorescu C, Reinier K, Dervan C, Uy-Evanado A, Samara M, Mariani R, et al., Factors Associated With Pulseless Electric
Activity Versus Ventricular Fibrillation: The Oregon Sudden Unexpected Death Study. Circulation 2010: 122(21);2116-22
Corresponding with a continuing decline in the prevalence of sudden cardiac arrest cases presenting with ventricular fibrillation (VF),
there has been a significant rise in the prevalence of pulseless electrical activity (PEA). Given significantly lower survival from PEA
versus VF, we comprehensively investigated PEA correlates by incorporating first-responder data with lifetime clinical history
information. Methods and Results: In the Portland, Oregon, metropolitan area (population ~1 million), cases of out-of-hospital
sudden cardiac arrest who underwent attempted resuscitation were identified prospectively (2002-2007). Those presenting with
PEA versus VF and asystole were compared with χ2 tests, ANOVA, and logistic regression. A total of 1277 cases aged >18 years
underwent resuscitation by first responders (mean age, 65+/-16 years; 67% male). Presenting arrhythmia was VF in 48%, PEA in 25%,
and asystole/other in the remainder. Compared with VF cases, PEA cases were older (mean age, 68 versus 63 years; P=0.0002), more
likely to be female (37% versus 26%; P=0.0008), and less likely to survive to hospital discharge (6% versus 25%; P<0.0001). A history
of syncope was strongly associated with PEA (odds ratio, 2.6; confidence interval, 1.3 to 5.3) after adjustment for age, gender,
response time, and arrest circumstances. Black race was also independently associated with PEA (odds ratio, 2.6; confidence
interval, 1.3 to 5.4). Pulmonary disease and female gender were significant factors associated with PEA (P for interaction=0.04). In a
subgroup analysis of resting ECGs (n=391), there were no differences in cardiac clinical history or prevalence of cardiac conduction
system disease (PEA, 31.6% versus VF, 32.2%; P=0.48). Conclusions--PEA cases had a significantly higher prevalence of syncope in
their lifetime, with other correlates, including black race, that were distinct from VF cases. Potential mechanistic links between
syncope and future manifestation with PEA warrant further exploration.
Section 11: ALS
27. Weeke P, Folke F, Gislason G, Lippert F, Olesen J, Andersson C, et al., Pharmacotherapy and hospital admissions before outof-hospital cardiac arrest: A nationwide study. Resuscitation 2010: 81(12);1657-63
For out-of-hospital cardiac arrest (OHCA) to be predicted and prevented, it is imperative the healthcare system has access to those
vulnerable before the event occurs. We aimed to determine the extent of contact to the healthcare system before OHCA. All
patients in Denmark with a registered OHCA June 1, 2001–December 31, 2005 were matched on age and sex with 10 random
16
Australian Research Council – November 2010 Research Updates
controls from the entire Danish population. We estimated the association with OHCA by conditional logistic regression analyses, and
we determined the proportion of patients in contact with the healthcare system before OHCA from hospital admissions or claimed
prescriptions. We identified 12,089 patients with an OHCA. Of these, 62% (7548) and 85% (10,312) were in contact with the
healthcare system up to 30 days and 1 year before OHCA, respectively. Association with OHCA up to 30 days before the event
pertained to myocardial infarction (odds ratio (OR)=6.4, 95% confidence interval (CI): 4.7–8.6)); heart failure (OR=5.1, CI: 4.1–6.3);
ischemic heart disease (OR=1.9, CI: 1.6–2.4); and cardiac dysrhythmia (OR=1.8, CI: 1.4–2.2). Concomitant pharmacotherapy up to 30
days before OHCA with the strongest association was: corticosteroids (systemic) (OR=2.7, CI: 2.5–3.0), bronchial dilators (OR=2.5, CI:
2.3–2.7), anti-psychotic medication (OR=2.1, CI: 1.9–2.3), and digoxin (OR=2.1, CI: 2.0–2.3). Similar results were found for
associations up to 1 year before OHCA. Contrary to general belief, the majority of OHCA patients are in contact with the healthcare
system shortly before OHCA.
28. Whyte AJ, Kehrl T, Brooks DE, Katz KD and Sokolowski D, Safety and Effectiveness of Acetadote for Acetaminophen Toxicity. J
Emerg Med 2010: 39(5);607-11
Background: Acetaminophen (APAP) toxicity is commonly encountered in the Emergency Department. Until 2004, treatment
consisted of either oral N-acetylcysteine (NAC) or filtered oral NAC administered intravenously (i.v.). Intravenous acetylcysteine
(Acetadote) is a new Food and Drug Administration-approved i.v. formulation of acetylcysteine manufactured by Cumberland
Pharmaceuticals in Nashville, Tennessee. Little post-marketing data exists on the effectiveness and safety of i.v. acetylcysteine.
Objectives: We evaluated the clinical presentations and outcomes of patients treated with i.v. acetylcysteine for APAP toxicity.
Methods: We performed a retrospective chart review of patients treated with i.v. acetylcysteine for APAP ingestion. The primary
outcome measures were: adverse reactions to and effectiveness of i.v. acetylcysteine, as defined by elevation of transaminases, liver
failure, renal failure, death, and hospital length of stay (LOS). Data collected included: comorbidities, allergies, intentionality, timing
and dosing of i.v. acetylcysteine, hospital LOS, transaminases > 1000 IU/L, development of liver failure requiring transplant,
development of renal failure requiring hemodialysis, death, and anaphylactoid reactions. Results: Sixty-four patients met our study
criteria. Overall, 16 (25%) patients developed transaminases > 1000 IU/L, 4 (6%) of them died and 2 (3%) received liver transplants.
Of the 15 patients (23%) treated within 8 h, none died or developed liver or renal failure, and only 1 developed transient
transaminase elevation > 1000 IU/L. In the patients treated outside of 8 h, the median LOS was 3 days, whereas the group treated
within 8 h had a median LOS of only 1 day. Six (9%) patients developed anaphylactoid reactions, 2 of whom received the i.v.
acetylcysteine bolus over 15 min. Five of these patients were treated pharmacologically and completed treatment, and one had
treatment discontinued for undocumented reasons. Conclusion: Intravenous acetylcysteine seemed to be a safe and effective
formulation of N-acetylcysteine.
17
Australian Research Council – November 2010 Research Updates
SELECTED ABSTRACTS FROM THE 2010 AHA SCIENTIFIC SESSIONS
(Complete list of abstracts are in Circulation supplement 2010 122(21_Meeting abstracts))
29. Berger S, Campbell R, Drezner J, Wilson J, Ellison A, Kessel M, et al., Abstract 12205: Saving Lives in Schools -- School-based
CPR-AED Programs: Awareness, Education, Planning and Partnerships. Circulation 2010: 122(21_MeetingAbstracts);A12205
Background: Sudden cardiac death (SCD) in the young is devastating. 20% of the U.S. adult and pediatric population spends time in
schools each week, making schools a strategic location for secondary prevention through CPR-AED programs. Purpose: We sought to
describe the impact of school based CPR-AED programs. Methods: Project ADAM (PA) (Milwaukee, WI) and Project SAVE (Atlanta,
GA) are community programs designed to prevent SCD in schools. The goals are directed toward schools, including (1)
education/awareness of signs, symptoms, treatment of SCA, (2) implementation of CPR-AED programs in schools (3) advocacy for
students to learn CPR/AED use prior to graduation. SCA events are monitored at existing participating schools. A comprehensive
program includes a coordinator, EMS, first responder team development/training, purchase/maintenance of AED(s) and an
emergency response plan. Results: WI: 850 schools have CPR-AED programs (35% of all WI schools). All schools in the Milwaukee
Public School system have a program and 70% of high schools have programs. Across WI, in schools where an AED was deployed at
the time of a SCA, there was a 36% rate of survival to hospital discharge. Since PA started, 11 "saves" are a result of school
programs: 6 adults, 5 children/adolescents. GA: Project SAVE has provided CPR-AED program information to all 180 school districts
in GA. 65% of all schools have AEDs and a HeartSafe program has been recognized in 728 schools (32% of schools). From Oct 2004 —
May 2010: 49 (26 students; 23 adults) SCA events have been reported in GA schools. Due to improved school AED and emergency
response plans, 22 of the incidents have resulted in survival to hospital discharge (45% total survival rate, 10 students; 12 adults).
Many student SCAs did not occur with high school sports (2 elementary, 6 middle, and 18 high school). Diagnoses in the
child/adolescent survivor group include LQTS, CA from the opposite sinus of Valsalva, HCM, Kawasaki disease, aortic stenosis, WPW,
commotio cordis and lightning strike. Conclusions: Community programs designed to assist schools implement school CPR-AED
programs are successful and lead to a high survival rate for SCA occurring in schools.
Guideline 9.2: Teaching resuscitation in schools
30. Blewer AL, Leary M, Decker CS, Andersen JC, Fredericks AC, Bobrow BJ, et al., Abstract 17196: Hands-only CPR Video Selfinstruction Promotes Self-confidence and Secondary Training: A Hospital-based Randomized Trial. Circulation 2010:
122(21_MeetingAbstracts);A17196
Background: Recent work suggests that hands-only CPR (omitting rescue breaths) is an acceptable layperson resuscitation strategy.
It is unknown whether training in hands-only CPR or standard CPR (30 compressions:2 breaths) engenders more rescuer confidence
18
Australian Research Council – November 2010 Research Updates
or encourages wider dissemination. Objectives: We hypothesized that laypersons receiving video self-instruction (VSI) CPR training
will be more confident in their skills and more likely to share the VSI kit with additional family members (secondary training), when
randomized to hands-only CPR instruction versus training in standard CPR. Methods: In a multisite trial of CPR educational
strategies, family members of hospitalized cardiac patients were trained in CPR using an established VSI kit. Subjects were
randomized to standard or hands-only modes of CPR education, using videos with the same actor and similar video duration. CPR
skills and subject impressions on training were then assessed. The magnitude of secondary training was measured via survey one
month after initial instruction. Results: Of 1038 individuals screened, 380 consented to CPR training. Enrolled subject mean age was
53±14 years, 307/380 (81%) were spouses/immediate family of the hospitalized patients and 319/380 (84%) were never CPR trained
or had not received training in over 10 years. Skills performance was indistinguishable between the hands-only and standard CPR
groups (checking responsiveness, calling for help, compression rate/depth). Trainees in the hands-only group were significantly more
likely to rate themselves "very comfortable" with the idea of using CPR skills in an actual event than standard group trainees (71 vs
50, p=0.01). Subjects were contacted one month after initial training to assess secondary training. VSI kits were shared with a mean
of 3.8±4.2 additional family members in the hands-only group versus 3.2±2.6 in the standard CPR group (p=NS). Conclusions: Handsonly CPR education resulted in a statistically significant increase in self-confidence compared to standard CPR training, and a trend
towards increased secondary training using VSI kits. This work suggests that implementation of VSI training programs using handsonly CPR may confer broader dissemination of life-saving skills.
Guideline 9.11: CPR training
31. Brooks SC, Cheng HC, Chan JY, Beecroft J, Morrison LJ and Chan TC, Abstract 12337: Modeled Geographic Optimization of
Public Access Defibrillator Locations. Circulation 2010: 122(21_MeetingAbstracts);A12337Introduction: Mortality after out-of-hospital cardiac arrest (OHCA) is very high. Early defibrillation improves chances of survival.
Bystanders rarely use automated external defibrillators (AEDs). Hypothesis: Current geographical deployment of AEDs in the Toronto
and Peel Regions of Ontario can be improved using optimization techniques. Objectives: 1) Quantify the current coverage of
historical OHCAs with registered AEDs; 2) Develop a strategy to optimize future AED placement using mathematical modeling
techniques. Methods: The Resuscitation Outcomes Consortium Epistry — Cardiac Arrest is a large epidemiologic registry of
consecutive OHCAs. To assess the current deployment of public access AEDs registered with emergency medical dispatch, we
measured distance and time metrics relative to public location cardiac arrests in our study region occurring between 01/01/2006
and 11/30/2009. Using geographic information systems technology and the maximal covering location model, we determined
optimal locations for the placement of future AEDs. Results: We analyzed 1,414 public-location out-of-hospital cardiac arrests. There
were 2,041 pre-existing registered AEDs providing coverage (within 100 meters) for only 226 of these episodes (16.0%). The average
19
Australian Research Council – November 2010 Research Updates
distance to the closest AED was 487 ± 779 meters. The average bystander travel time to the closest AED was 4.87 ± 7.79 minutes
(walking at 100 m/minute). Using our optimization model, we determined that the top five locations for additional AED placement
would cover an additional 51 OHCAs. A minimum of 884 additional AEDs would be required to cover all historical public location
OHCAs with sequential priority placement of AEDs resulting in one-to-one coverage after approximately 200 new AEDs (Figure 1).
Conclusions: Distribution of registered AEDs in the study region is sub-optimal. Modeling has the potential to improve AED
distribution, usage and survival after public location OHCA.
Guideline 7: Automated external defibrillators in BLS
32. Choi J-H, Shin TG, Jo IJ, Sim MS, Song HG, Jeong YK, et al., Abstract 16388: Comparison of Extracorporeal Cardiopulmonary
Resuscitation with Conventional Cardiopulmonary Resuscitation in Patients with In-Hospital Cardiac Arrest: A Propensity Score
Analysis. Circulation 2010: 122(21_MeetingAbstracts);A16388
Introduction: Whether the survival of in-hospital cardiac arrest victims could be extended by extracorporeal cardiopulmonary
resuscitation (E-CPR) supported with extracorporeal membrane oxygenation (ECMO) compared to conventional CPR (C-CPR) is still
not well determined. Methods: We retrospectively analyzed a total of 406 adult patients with witnessed in-hospital cardiac arrest
receiving CPR more than 10 minutes, from January 2003 to June 2009 (85 in the E-CPR and 321 in the C-CPR). Results: The primary
endpoint was a survival discharge with minimal neurologic impairment. Propensity score matching was used to balance the baseline
characteristics and CPR variables that could potentially affect prognosis. In the matched population (n = 120), the survival discharge
rate with minimal neurologic impairment in E-CPR group was significantly higher than C-CPR group (23.3% versus 5% odds ratio[OR]
0.17, 95% confidence interval[CI] 0.04 to 0.63, p =0.008). In addition, there was a significant difference in the six-month survival with
minimal neurologic impairment(hazard ratio[HR] 0.51, 95% CI 0.34 to 0.77, p<0.001 by log-rank test). In subgroup with cardiac
origin, E-CPR also showed a benefit in survival discharge(OR 0.19, 95% CI 0.05 to 0.75, p=0.018) and 6-month survival with minimal
neurologic impairment(HR 0.55, 95% CI 0.34 to 0.88, p=0.013; p=0.002 by log-rank test) Conclusions: E-CPR showed a survival
benefit over C-CPR in patients with witnessed in-hospital arrest, who received CPR of more than 10 minutes, especially with cardiac
origin.
33. Dumas F, Grimaldi D, Zuber B, Fichet J, Demars N, Marx JS, et al., Abstract 15755: Hypothermia After Cardiac Arrest: Effective
in Both Shockable and Non-Shockable Patients? Circulation 2010: 122(21_MeetingAbstracts);A15755Introduction: Management of out-of-hospital cardiac arrest (OHCA) survivors routinely includes mild therapeutic hypothermia (MTH)
in order to improve cerebral outcome. Although the level of evidence of improvement is high in patients resuscitated from a
shockable rhythm (Ventricular Fibrillation or pulseless Ventricular Tachycardia: VF/VT), data are more controversial in non shockable
20
Australian Research Council – November 2010 Research Updates
patients (Pulseless Electrical Activity or asystole: PEA/asystole). We therefore assessed the prognostic value of hypothermia on
neurological outcome at hospital discharge according to first recorded cardiac rhythm. Methods: Between Jan 2000 and Dec 2009,
1145 consecutive OHCA patients in whom a successful resuscitation has been achieved were admitted to our intensive care unit in
Paris (France). All clinical and biological characteristics during pre-hospital care and intensive care unit stage were prospectively
collected. The association of MTH with a good neurological outcome at hospital discharge (Cerebral Performance Categories-CPClevel 1 or 2) was quantified by logistic regression. Results: Among the 1145 successfully resuscitated OHCA, 708 (68%) had an initial
VF/VT rhythm. MTH was induced in 457/708 pts (65%) in VF/VT and 261/437 pts (60%) in asystole/PEA. Overall 345/1145 pts (30%)
reached a CPC level 1 or 2 at hospital discharge, respectively 274/708 (39%) in VF/VT and 68/437 (16%) in asystole/PEA (p<0.001). In
VF/VT patients, the use of MTH was positively related to good outcome (OR=1.90; CI95% [1.18–3.06]) after adjustment for pre- and
in-hospital covariates. By contrast, in asystole/PEA patients, the use of MTH tended to be inversely associated with good outcome,
although it did not reach statistical significance (adjusted OR=0.71; CI95% [0.37–1.36]). Conclusions: In this large cohort of OHCA
patients, induced MTH was independently associated with a better neurological outcome at hospital discharge in patients presenting
a shockable rhythm (VF/VT). By contrast, this benefit was absent in non-shockable patients, in whom MTH tended to be associated
with a worse neurological outcome. Further investigations are needed to clarify this lack of efficiency in PEA/asystole.
Guideline 11.8: Therapeutic hypothermia after cardiac arrest
34. Fumagalli F, Ristagno G, Li Volti G, Santangelo R, Russo I and Latini R, Abstract 166: High Dose of Epinephrine Administered
During Cardiopulmonary Resuscitation Leads to Greater Oxidative Stress Following Resuscitation From Cardiac Arrest. Circulation
2010: 122(21_MeetingAbstracts);A166
Introduction: Optimal dose of epinephrine to be used during CPR is controversial. Nevertheless, epinephrine has been recognized to
increase ischemic injury. Oxidative stress that follows ROSC is another adverse event associated with cardiac resuscitation. We
hypothesized that higher dose of epinephrine compared to the standard dose will cause greater systemic oxidative stress. Methods:
Ventricular fibrillation was induced in 12 SD rats, 430 ± 30 g, and untreated for 6 mins. CPR, including mechanical chest compression
and ventilation, was then initiated and continued for 6 mins prior to defibrillations. Animals received i.v. injection of either a
standard dose of epinephrine (20 µg/kg) or a higher dose of epinephrine (200 µg/kg), at 2 min after the start of CPR. Two hrs
following ROSC, myocardial function was echocardiographically assessed. Animals were then sacrificed and organs harvested for
lipid hydroxides (LOOH) measurement, as markers of cell membrane lipid peroxidation and thereby of oxidative stress. Results: No
differences in coronary perfusion pressure (CPP) were observed between the two groups. All the animals treated with lower dose of
epinephrine achieved ROSC while only 2 of 7 in the higher dose. Post ROSC myocardial function was greater in animals resuscitated
after higher dose of epinephrine (table). LOOH in heart, brain, liver and kidney increased after resuscitation. However, after higher
21
Australian Research Council – November 2010 Research Updates
dose of epinephrine LOOH levels increased more than double compared to standard dose. Conclusions: High dose of epinephrine
compared to standard dose improved neither CPP nor ROSC, but it caused higher myocardial dysfunction and greater oxidative
stress response.
Guideline 11.5: Medications in cardiac arrest
35. Gianotto-Oliveira R, Gonzalez MM, Oliveira GG, Zanocelo TM, Munhoz BD, Quilici Ap, et al., Abstract 16252: Influence of Body
Mass Index in the Quality of Cardiopulmonary Resuscitation. Circulation 2010: 122(21_MeetingAbstracts);A16252
Background: Studies have suggested that even health care providers do not perform effective Cardiopulmonary Resuscitation (CPR).
There are several factors that can interfere in the quality of CPR. Hypothesis: We hypothesized that those medical students with
normal body mass index could perform better CPR maneuvers when compared with those with higher body mass index (BMI).
Methods: We trained 82 medical students from first year through the "Family and friends CPR anytime" course. Four weeks after the
course, two minutes of chest compressions were performed to the Resusci Anne manikin with the PC skill reporting system. Initially
all students had their weight and high measured hence the calculation of BMI was made. The quality of chest compressions was
compared among students with normal BMI (Group A) and those overweight and obese (Group B). Results: The distribution of
students considering BMI was 65.9% with normal BMI (Group A) and 24.5% with overweight, 4.8% were graded as obese I and 4.8%
graded as obese II (Group B). The mean age of group A was 20.2 ±2.7 years and of group B was 21.6 ±3.7 years. No significant
differences between the sex of the two groups was observed (46.3% and 63%, p=0.314 for male sex, respectively). The total number
of compressions (189.9 vs. 188.1), the average of rate compressions per minute (93.8 vs. 92.6) and the right hands position (173.3
vs. 164.5) did not show significant differences (p=0.7569, p=0.6783, p=0.6145, respectively) despite the BMI. The average chest
compressions with adequate depth during the two minutes were different between the two groups: 90.3 (47.9%) in Group B and
43.4 (22.5%) in Group A, p=0.0004. Conclusion: The depth of chest compressions was higher in the overweight group, but not yet the
ideal depth, while no differences was observed in rate of compressions per minute and hands position between the two groups.
These findings reinforce the need for devices which measure the depth of chest compressions during CPR maneuvers.
36. Jacobs I, Finn J, Jelinek G, Oxer H and Thompson P, Abstract 1: A Randomised Placebo Controlled Trial of Adrenaline in
Cardiac Arrest - the PACA Trial. Circulation 2010: 122(21_MeetingAbstracts);A1
Background: Adrenaline (Epinephrine) remains the primary pharmacological agent in cardiac arrest. Despite a total absence of any
experimental trials to establish efficacy, adrenaline is considered standard of care in resuscitation. Methods: We undertook a
double-blind randomised placebo controlled trial of adrenaline in out-of-hospital cardiac arrest in Perth, Western Australia between
August 2006 and November 2009. Patients were randomly assigned to receive either 1 ml aliquots of adrenaline 1:1000 or Sodium
22
Australian Research Council – November 2010 Research Updates
Chloride (0.9%) by means of computerised random number generator. Primary outcome was survival to hospital discharge and
secondary outcomes included return of spontaneous circulation (ROSC) and neurological outcome (Cerebral Performance Category
Score) at hospital discharge. Odds ratios (OR) and 95% confidence intervals were derived for these outcomes and analysis was on an
intention to treat basis. Results: During the study period paramedics attended 4107 cardiac arrests of which resuscitation was
commenced in 1586 (38.6%) patients. Of these 602 (37.9%) were enrolled into the study with a further 67 (11.1%) being excluded
after randomisation. Of the remaining 535 patients 262 (48.9%) and 273 (51.0%) received placebo or adrenaline respectively. The
percentage male (70.6% versus 74.8%); mean age (64.8 versus 65.4 years) and percentage of patients who received bystander CPR
(55.7% versus 53.1%) were similar for the adrenaline and placebo groups respectively. ROSC was achieved in 83 (30.4%) patients
receiving adrenaline and 29 (11.1%) receiving placebo - OR= 3.51 [95% CI 2.21 to 5.58]. Survival to hospital discharge occurred in 11
(4.1%) and 5 (1.9%) of the adrenaline and placebo patients respectively - OR= 2.16 [95% CI: 0.74 to 6.30] Conclusions: The use of
adrenaline in cardiac arrest was associated with a significant increase in the proportion of patients achieving ROSC however this
improvement did not extend to survival to hospital discharge. As our results are unable to rule out a clinically meaningful benefit of
adrenaline in terms of survival to hospital discharge, further investigation into the post resuscitation period for those achieving ROSC
is required in order to identify management strategies to improve survival.
Guideline 11.5: Medications in cardiac arrest
37. Kheir JN, Scharp L, Walsh B and McGowan FX, Abstract 6: Intravenous Oxygen Gas-Filled Liposomes Prevent Death From
Asphyxia. Circulation 2010: 122(21_MeetingAbstracts);A6
Introduction: Hypoxemia contributes to cellular dysfunction and death in a number of disease states. We investigated the possibility
of administering clinically-relevant volumes of oxygen gas to the body via the intravenous route using a model of asphyxia.
Hypothesis: We hypothesized that we could reduce hypoxemia and prolong survival by administering an infusion of oxygenated
liposomes in an experimental model of asphyxia. Methods: We manufactured oxygen gas-filled liposomes by sonication, floatation
and centrifugation. Liposome diameter was determined by light scatter, and oxygen content determined by weight differential of a
set volume of suspension. To test the hypothesis, adult rabbits (n=6) were anesthetized, paralyzed, mechanically ventilated, and
instrumented. Following stabilization on FiO2 21%, the endotracheal tube was clamp-occluded. Following onset of hypoxia,
oxygenated liposomes or oxygenated PlasmaLyte (vehicle control) were infused at the rate of measured oxygen consumption. This
was continued until either loss of circulation (loss of pulse pressure) or 13 minutes passed, whichever came first. Arresting animals
were resuscitated with 100% oxygen and ACLS protocols. Endpoints included hemodynamic parameters and ABG. All animals were
survived for 2 hours. Results: The oxygenated liposomes utilized in this study exhibited a mean diameter of 2.05±1.86 microns, and
contained 60.1 mL of oxygen gas per dL of suspension. Mean oxygen consumption was 19.3 mL/min. When compared with animals
23
Australian Research Council – November 2010 Research Updates
treated with oxygenated crystalloid, animals treated with infusions of liposomal oxygen gas exhibited (1) no arrest at 13 min
endpoint (time to CPR in controls: 6.7 [95% CI 4.0–9.3] mins, p<0.05), (2) significantly higher arterial oxygen tensions and saturations
(Fig A,B), and (3) absence of severe hypotension . Conclusion: Oxygenated liposomes can deliver sufficient oxygen to prevent critical
hypoxia in a clinically relevant model of asphyxia.
38. Knudson JD, Neish SR, Cabrera AG, Morales DL, Zafar F, Graves DE, et al., Abstract 15880: Prevalence and Outcome of
Pediatric In-Hospital Cardiopulmonary Resuscitation in the United States: An analysis of the Kids' Inpatient Database. Circulation
2010: 122(21_MeetingAbstracts);A15880
Introduction: Population-based data on in-hospital cardiopulmonary resuscitation (CPR) in children in the United States are scarce.
Studies from single centers and voluntary registries may skew the prevalence and outcomes of CPR. Hypothesis: CPR is not a rare
occurrence in hospitalized pediatric patients in the United States and that many patients would survive to hospital discharge. Risk
factors for CPR and death after CPR were determined. Methods: A retrospective analysis of the Healthcare Cost and Utilization
Project (HCUP) Kids' Inpatient Database was performed for children receiving inpatient CPR in 2006. The database is a nationwide
sampling of pediatric hospital discharges and is weighted to provide national estimates (analyses were performed using weighted
values). Results: CPR was performed in 5807 (95% CI 5,259 to 6,355) hospitalized children with a prevalence of 0.77 per 1,000
admissions. Most patients (68%) were < 1 year old and 44% were female. Extracorporeal membrane oxygenation (ECMO) was
uncommon (3%). On multivariable analysis, patients receiving CPR were more likely to have heart failure (OR 4.8, 95% CI 3.8 to 6.0),
cardiomyopathy (OR 4.9, 95% CI 4.1 to 6.0), acute renal failure (OR 23.2, 95% CI 19.3 to 27.9), respiratory failure (OR 31.7, 95% CI
27.6 to 36.5) and acute cerebrovascular disease (OR 3.9, 95% CI 3.1 to 5.0). Overall in-hospital mortality was 51.8% and greater
among patients ≥ 1 year (68%) versus < 1 year (44%) (OR 2.7 95% CI 2.3 to 3.2). On multivariable analysis, factors associated with an
increased risk of death among patients receiving CPR included acute renal failure (OR 1.5, 95% CI 1.1 to 1.9), age ≥ 1 year (OR 2.9,
95% CI 2.4 to 3.5), cancer (OR 1.8, 95% CI 1.1 to 2.9) and sepsis (OR 1.5, 95% CI 1.2 to 1.7). Conclusions: In this largest populationbased study of pediatric inpatient CPR, CPR occurred in approximately 1 in every 1,300 pediatric hospital admissions. Just over half
of the patients who received CPR did not survive to hospital discharge. ECMO was not frequently utilized. Risk factors for hospital
mortality among patients receiving CPR include older age, acute renal failure, cancer and sepsis. Further studies are needed to
confirm these findings and develop strategies to improve outcomes.
Section 12: Paediatric ALS
24
Australian Research Council – November 2010 Research Updates
39. Lee CH, Abstract 19179: Assessing Prehospital Resuscitation Quality Using Empirical Mode Decomposition Analysis of
Automatic External Defibrillator Records. Circulation 2010: 122(21_MeetingAbstracts);A19179
Methods: AED tracings during prehospital CPR sessions were obtained and digitized. An algorithm to automatically identify and
reconstruct rhythms associated with chest compression from these AED tracings was developed using empirical mode
decomposition (EMD). In the model, each mode of oscillation, termed intrinsic mode functions (IMFs), was decomposed sequentially
from the original time series by a sifting process. The significant fluctuations associated with adequate pressing pressure could be
reconstructed from the dominant IMF. Quality of CPR parameters in terms of no-flow time, no flow fraction, average compression
rates, time of inadequate CPR (rate < 90 or > 120 /min) were calculated according to uniformed reporting template proposed by
Kramer-Johnson. Quality of CPR parameters of the same tracings were assessed by experienced clinicians manually through
reviewing the audio and graphic recordings of the CPR sessions. Results: The first 5 minutes of prehospital CPR sessions among 50
asystole AED tracings underwent quality assessment by both EMD algorithm and manual review. Among the four quality
parameters, the correlation between EMD algorithm vs. manual analysis were high for average compression rates (r=0.87, p=0.000),
and time of inadequate CPR (r=0.79, p=0.000); and fair for no flow time (r=0.45, p=0.002) and no flow fraction (r=0.30, p=0.047).
Conclusions: Automatic algorithm analysis of widely available AED tracings provides a potential tool for assessing prehospital CPR
quality.
Guideline 7: Automated external defibrillators in BLS
40. Pre-Hospital Sudden Cardiac Arrest with Different Transthoracic Impedances. Circulation 2010: 122 (21_MeetingAbstracts);
A16068
Introduction: Modern external defibrillators use impedance compensation techniques because the transthoracic impedance (TTI) is
a major factor which influences the intracardiac current flow during electric shock and defibrillation success. Our previous study
demonstrated that current-based compensation outperformed duration-based compensation technique in a pig model of cardiac
arrest . In this study, we evaluated the performance of current-based impedance compensation technique in pre-hospital cardiac
arrest patients and related the shock success to the TTI measurement. Methods: ECG recordings, along with TTI measurements
between two shocking pads, were collected from multiple emergency medical services (EMS) in the USA through a regular field case
submission program sponsored by ZOLL Medical Corporation. All the EMSs in this study use ZOLL AED which employs current-based
impedance compensation technique. The electronic data do not contain patient identifiable information. The ECG tracings were
annotated by one independent doctor and verified by another independent doctor in order to enhance the data accuracy. Shock
success was defined as an organized rhythm that was present for a minimum of 30 seconds, started within 60 seconds after the
shock, and had a rate of 40 beats per minute or greater. Results: 632 shocks from a total of 300 patients were analyzed in this study.
25
Australian Research Council – November 2010 Research Updates
The shock success rate remained unchanged over the whole spectrum of TTI from 50 ohms to 250 ohms (average success rate is
22.5%, 23.0% for low impedance and 21.8% for high impedance shocks, p=0.77). No significant difference in odds of shock success
over TTI was observed (OR=0.998, p=0.23, 95% Conf. Interval=0.994 to 1.0001). Conclusion: The defibrillators with current-based
impedance compensation technique performed equally well in the whole range of TTI in the pre-hospital cardiac arrest.
Guideline 11.4: Electrical therapy for ALS
41. Malebranche LJ, Reddy VK, Hosmane VR, Zhang Z, Weintraub WS and Rahman E, Abstract 19239: Survival and Neurologic
Recovery in Patients With ST-Elevation After Resuscitation from Cardiac Arrest Found to Have Non-Obstructive Disease on
Angiography. Circulation 2010: 122(21_MeetingAbstracts); A19239
Methods: We examined records of 3502 consecutive patients at our institution suspected of having ST-Elevation myocardial
infarction (STEMI) from 1/1/02 to 12/31/08. One hundred thirty-five patients were found to have EKG evidence of STEMI after being
resuscitated from cardiac arrest. Of these, 129 were taken for emergent catheterization. Sixteen patients had non-obstructive
coronary disease (CAD) on catheterization with no obvious culprit lesion, while 113 had obstructive CAD. Endpoints were survival to
hospital discharge and neurologic recovery among the two groups. Results: Overall, 83 patients survived (64.3%) with 75 of the 129
(58.1%) having full neurologic recovery. After resuscitation, 37 were alert, 14 minimally responsive, and 78 were unresponsive. Of
the 113 patients with obstructive CAD, 96 were revascularized (PCI/Surgery). There was no statistically significant difference in
survival (43.8% vs 67.3%, p=0.067) or full neurologic recovery (37.5% vs 61.1%, p=0.081) between patients with non-obstructive vs
obstructive CAD. In patients that were initially unresponsive after resuscitation, overall survival was 43.6%. There was a trend
towards survival for non-obstructive compared to obstructive CAD in these unresponsive patients, but not significantly different.
(18.2% vs 47.8%, p=0.067). Unresponsive patients with non-obstructive CAD had a lower incidence of full neurologic recovery (9.1%
vs 39.7%, p=0.0455). Conclusions: There was no significant difference in survival or neurologic recovery between patients with STelevation on post-resuscitation EKG based on whether they had obstructive or non-obstructive CAD. STEMI patients who are initially
unresponsive after resuscitation are less likely to make full neurological recovery if they have non-obstructive versus obstructive
coronary disease.
42. Matsuzaki M, Nagao K, Soga T, Kasai A, Nonogi H, Yonemoto N, et al., Abstract 13937: Efficacy of Early Induction of
Therapeutic Hypothermia for Patients with Return of Spontaneous Circulation after Out-of-Hospital Cardiac Arrest (J-PULSE-Hypo
Study). Circulation 2010: 122(21_MeetingAbstracts);A13937
Background: Preclinical and clinical evidence strongly supports mild therapeutic hypothermia as an effective therapy for the postcardiac arrest syndrome. Animal data has demonstrated that the sooner cooling is initiated after return of spontaneous circulation
26
Australian Research Council – November 2010 Research Updates
(ROSC) from cardiac arrest, the better the outcome, although an impressive therapeutic benefit was seen in clinical studies when
cooling was delayed for several hours. It is not known whether the neurologically intact survival rate will increase if the cooling is
initiated on arrival at the emergency room. Methods: We did a multicenter observational study of therapeutic hypothermia for
unconscious adult patients with return of spontaneous circulation (ROSC) after out-of-hospital cardiac arrest. The J-PULSE
Hypothermia committee entrusted each hospital with the timing of cooling, cooling methods, target temperature, duration, and
rewarming rate. The primary endpoint was favorable neurological outcome at hospital discharge. Results: Of the 452 unconscious
adult patients who were treated with therapeutic hypothermia, 304 who were cooled to 34 °C after ROSC from out-of-hospital
cardiac arrest due to ventricular fibrillation were included; 159 received hypothermia using rapid intravenous (IV) infusion of ice-cold
0.9% saline or Ringer's lactate. Hypothermia was maintained using external devices or extracorporeal devices (IV group). 145
received hypothermia without IV cold fluid. Hypothermia was maintained using external devices or extracorporeal devices (non-IV
group). The time interval from collapse to initiation of the cooling was shorter in the IV group than in the non-IV group (a median; 53
minutes vs.165 minutes, p<0.0001). The IV group had higher frequency of favorable neurological outcome than the non-IV group
(69.8% vs.55.9%, p=0.012). A multiple logistic-regression analysis showed that the adjusted odds ratio for favorable neurological
outcome after the IV group was 1.83 (95% CI, 1.14–2.93, p=0.012).
Guideline 11.8: Therapeutic hypothermia after cardiac arrest
43. Pierick TA, Van Waning N, Patel S and Atkins D, Abstract 12388: Infant CPRAnytime: Self-Instructional CPR Training for
Parents of High Risk Infants. Circulation 2010: 122(21_MeetingAbstracts); A12388
Objective: Premature infants (PRE) and infants with congenital heart disease (CHD) have a high risk of respiratory or cardiac arrest
within the first year. Bystander CPR is a major predictor of resuscitation outcome. The purpose of this study was to assess usefulness
of a self-instructional DVD kit (Infant CPRAnytimeTM) for families of high risk infants. We hypothesized that comfort level of
providing CPR would increase, the kit would be shared with other caregivers and would be reviewed at regular intervals. Methods:
Parents of PRE infants (<35 wks or <2500 gms) or with CHD were given a self-instructional CPR kit. One parent completed a
questionnaire, reviewed the DVD, and practiced CPR before discharge. The parent was asked to share the kit with other care
providers, practice CPR every 3 months and respond to questionnaires at 4 and 12 month intervals. The questionnaire surveyed prior
CPR training, comfort level doing CPR on their child, plans to share the kit with other care providers and plans to review the kit. The
4 and 12 month surveys assessed comfort level performing CPR (5 point Likert scale), number of additional persons who reviewed
the kit, and how often the kit was reviewed by the parent. Results: We enrolled 311 parents: 238 in the PRE group and 73 in the CHD
group. Seventy-five percent of parents had prior CPR training. Comfort level increased from 2.8 at baseline to 3.3 at 4 months to 3.5
at 12 months (p value = 0.0281). The kit was shared with 2.8 additional persons and was reviewed by the parent 1.8 times over the
27
Australian Research Council – November 2010 Research Updates
12 month interval. There were 8 reported events with need for rescue: choking (3) and CPR (5). All events requiring CPR were in
infants with CHD. Six infants survived the event. Parents of these infants indicated that the CPR training was very useful.
Conclusions: There was a significant increase in caregiver comfort level at 4 and 12 months compared to baseline, despite a high
level of prior CPR training. There was a marked multiplier effect for the number of persons trained. Easily available self instruction
provides an excellent method of CPR training for parents of high risk infants and likely contributed to a high survival rate. Family
caregivers recognize Infant CPRAnytime TM as a useful method of learning CPR skills.
Guideline 9.1.1: CPR training, Section 12: Paediatric ALS
44. Ristagno G, Fumagalli F, Chung SP, Weng Y, Sun S, Weil MH, et al., Abstract 167: Selective Head Cooling Initiated During CPR
and Continued Following Return of Spontaneous Circulation Improves Coronary Perfusion Pressure and Myocardial Tissue
Perfusion After Cardiac Arrest. Circulation 2010: 122(21_MeetingAbstracts);A167
Background: We have reported that head cooling improved post resuscitation myocardial function, while systemic cooling by cold
saline intravenous infusion (CSI) did not. Nevertheless, CSI is now accepted as a simple method of inducing hypothermia. We
explored the effects of head cooling and CSI on myocardial perfusion. We hypothesized that head cooling would improve myocardial
perfusion. Methods: Ventricular fibrillation was induced in 15 pigs, 38 ± 1 kg, and untreated for 10 mins. CPR, including mechanical
chest compression and ventilation was then performed for 5 mins prior to defibrillation. Coincident with the start of CPR, animals
were randomized into: 1. head cooling with the RhinoChill device; 2. systemic cooling by CSI (30 mL/kg 4°C, in 30 mins) followed by
surface cooling; or 3. control. Aortic, right atrial and coronary perfusion pressures (CPP) were continuously measured, together with
rectal and brain temperatures. Myocardial perfusion was assessed using colored microspheres (diameter 10 ± 0.2 µm) technique.
Results: All the animals with the exception of one control were successfully resuscitated. Head cooling rapidly decreased the brain
temperature (p < 0.01). CSI significantly decreased both brain and rectal temperatures (Table). Animals subjected to head cooling
showed significantly higher CPP following resuscitation. These increases in CPP were accompanied by improvements in myocardial
perfusion (p < 0.01, Fig). Those beneficial effects were not observed during CSI. Conclusions: Head cooling, but not systemic cooling,
initiated during CPR and continued following resuscitation, improved CPP and myocardial perfusion after cardiac arrest.
Guideline 11.8: Therapeutic hypothermia after cardiac arrest
45. Rittenberger JC, Holm MB, Guyette FX, Tisherman S and Callaway CW, Abstract 281: Initial Illness Severity Not Hypothermia
Treatment is Associated With Outcome After Cardiac Arrest. Circulation 2010: 122(21_MeetingAbstracts);A281
Background: The effect of illness severity on response to therapeutic interventions for cardiac arrest such as therapeutic
hypothermia (TH) is unknown. This study examined the effects of TH on survival and functional outcome when subjects were
28
Australian Research Council – November 2010 Research Updates
categorized by early illness severity after cardiac arrest. Methods: Retrospective review of data from adults treated after in-hospital
or out-of-hospital cardiac arrest in a single tertiary care facility between before and after implementation of a TH program between
1/1/2005 and 12/31/2009. In addition to clinical data, initial illness severity was measured using serial organ function assessment
(SOFA) scores and full outline of unresponsiveness (FOUR) scores at hospital or intensive care unit arrival. Outcomes were hospital
mortality, good outcome (discharge to home or rehabilitation) and development of multiple organ failure (MOF). Results: Complete
data from 459/497 (92%) subjects identified distinct categories of illness severity using combined FOUR motor and brainstem
subscales, and combined SOFA cardiovascular and respiratory subscales: I. Awake; II. Moderate coma without cardiorespiratory
failure; III. Moderate coma with cardiorespiratory failure; and IV. Severe coma. Survival was independently associated with
category (II: OR 0.31; 95% CI 0.17, 0.55; III: OR 0.19; 95% CI 0.1, 0.36; IV: OR 0.03; 95% CI 0.01, 0.05). Category was also associated
with good outcome and development of MOF. Survival from ventricular fibrillation (VF) cardiac arrest increased after
implementation of TH. However, the proportion of subjects in each category changed over time. When adjusted for category, there
was no effect of TH on survival, good outcome and development of MOF. None of these outcomes improved within a category after
implementation of TH. Conclusions: Initial illness severity explains much of the variation in cardiac arrest outcome. The beneficial
effects of TH need to be reassessed taking illness severity into account.
Guideline 11.8: Therapeutic hypothermia after cardiac arrest
46. Sasaoka T, Yonemoto N, Yokoyama H, Nonogi H and J-RCPR Investigators, Abstract 16789: Impact of Underlying Diseases on
the Prognosis in Patients with Inhospital Cardiac Arrest; from the Japanese Registry of CPR for Inhospital Cardiac Arrest (J-RCPR).
Circulation 2010: 122(21_MeetingAbstracts);A16789
Background: In-hospital cardiopulmonary arrest (IHCPA) is an important factor of all cause of death. Although National Registry of
Cardio Pulmonary Resuscitation (NRCPR) from United States has reported the rate of discharge was 18%, the impact of underlying
disease on IHCPA remains unknown. Method: A total of 491 consecutive adults with IHCPA were registered in J-RCPR as a
multicenter trial. They were divided into two groups according to the underlying diseases; cardiovascular disease (Group C, n=265,
including ACS/Arrhythmia/Heart failure/Aortic diseases), and non-cardiovascular disease (Group N, n=226). Result: Baseline
characteristics of sex, age did not show significant difference in Group C and Group N. In group C (Group N), the prevalence of VF/VT
as first documented rhythm was 38.5% (16.4%, p<0.0001), asystole was 20.8% (39.8%, p<0.0001), and pulseless electrical activity
was 39.6% (41.2%, N.S.). The prevalence of witnessed IHCPA was significantly higher in Group C than Group N (85.7% vs. 66.4%,
p<0.0001). The percentage of IHCA within 2 days of hospitalization was significantly higher in Group C (46.0% vs. 30.1%, p<0.001).
The place and the direct cause of IHCPA were different in each group. In group C, the rate of survival on 24 hours and 30 days after
IHCPA was significantly higher than Group N (57.0%, 36.6% vs. 42.5%, 18.6%, p<0.001 respectively.), even though the rate of return
29
Australian Research Council – November 2010 Research Updates
of spontaneous circulation (ROSC) was not significantly different. The rate of the favorable neurological function (CPC 1–2) among
patients survived at 30 days after IHCPA was also higher in Group C (82.4% vs. 45.9%, p<0.001). Conclusion: Group C (cardiovascular)
showed higher incidence of IHCPA in the early period of hospitalization and VT/VF as first documented rhythm. Also, they showed
better survival and neurological outcome from IHCPA. These results suggest the importance of intensive care in the early period of
hospitalization in patients with cardiovascular disease.
47. Shirai S, Ando K, Soga Y, Nagao K, Nonogi H, Yokoyama H, et al., Abstract 14823: Impact of Hyperglycemia at Admission on
Thirty Days Clinical Outcomes for the Out-of-hospital Cardiac Arrest of Patients Acute Coronary Syndrome Undergoing Coronary
Intervention with Hypothermia Therapy. Circulation 2010: 122(21_MeetingAbstracts);A14823
Background: Hyperglycemia affected the clinical result of acute myocardial infarction underwent coronary intervention. The aim of
this study was to evaluate the effect of hyperglycemia at admission on the 30-days clinical outcomes of the patients (pts) with
cardiac arrest due to acute coronary syndrome (ACS) undergoing percutaneous coronary intervention (PCI) with mild therapeutic
hypothermia (MHT). Methods: Data over a five-year period (2005–2009) were obtained for 452 patients treated with MHT from a
multicenter registry in Japan. Of these patients, all of 193 pts were diagnosed with ACS by emergency angiography immediately after
recovery of spontaneous circulation (ROSC), and were subsequently treated with MHT and PCI. These patients were divided into
groups based on the blood glucose (BS) at admission; Group A: BS at admission >300mg/dl and Group B: BS at admission
=<300mg/dl. Cerebral performance category (CPC) with levels 1 (Normal mental performance), 2 (moderate disability), 3 (severe
disability), 4 (vegetative state), 5 (death) was used at 30days. Poor neurologic outcome was defined in CPC 3, 4 and 5. Results:
Patient demographics of Group A (n=71) were younger (mean age 58 vs. 64, p<0.0001), longer time from arrest to ROSC (42min. vs.
30 min., p=0.0018). The proportions of shockable rhythm and the time to achieve target temperature were not different. There was
no significantly different in survival rate (74.1% vs. 79.1%, p=0.4775) between the two groups, however, neurologic outcome was
significantly better in group B compared with group A (35.2% vs. 60.0%, p=0.0010). Logistic regression analysis revealed that the
predictors of poor neurologic outcome were shockable rhythm (Odds ratio [OR]: 12.0, p<0.0001), age over 70 (OR: 7.7, p<0.0001),
time from collapse to ROSC (OR 4.3, p<0.0001), and BS at admission over 300mg/dl (OR: 2.8, p=0.0060). Conclusions: Hyperglycemia
at admission did not affect the mortality; however, had an impact on neurologic outcome for the patients with ROSC after cardiac
arrest due to ACS undergoing PCI with MHT.
30
Australian Research Council – November 2010 Research Updates
48. Shirai S, Nagao K, Tachibana E, Nishikawa K, Yagi T, Yonemoto N, et al., Abstract 11341: Comparison of a 30: 2 CompressionVentilation Ratio with a 15: 2 Compression-Ventilation Ratio for Patients Who Received Bystander Cardiopulmonary
Resuscitation After Out-of-Hospital Cardiac Arrest. Circulation 2010: 122(21_MeetingAbstracts);A11341
Background: The AHA 2005 guidelines for cardiopulmonary resuscitation (CPR) and emergency cardiovascular care (ECC) have
recommended that lay rescuers use a 30:2 compression-ventilation ratio for all victims with out-of-hospital cardiac arrest. It is not
known whether the neurologically intact survival rate will increase if lay rescuers perform CPR with a 30:2 compression-ventilation
ratio. Methods: The JCS-ReSS investigated the effect of the change to a 30:2 compression-ventilation ratio for CPR, compared with a
15:2 compression-ventilation ratio. Data of patients with out-of-hospital cardiac arrest from the all-Japan Utstein Registry of the Fire
and Disaster Management Agency were analyzed. The primary end point was a 30-day neurologically intact survival. Results: Of the
19,480 patients with witnessed out-of-hospital cardiac arrest due to cardiac etiology, with an age of 8 years and over, and with
shockable cardiac arrest rhythm on EMS arrival at the patients side, 3,764 patients who received CPR with chest compression plus
mouth-to-mouth ventilation by citizens (family or unrelated persons) were included; 1,992 received a 15:2 compression-ventilation
ratio in the 2000 CPR guidelines era (the 15:2 group), 1,772 received a 30:2 compression-ventilation ratio in the 2005 CPR guidelines
era (the 30:2 group). The 30:2 group had higher proportions of 30-day neurologically intact survival than the 15:2 group among all
patients in the study (23.6% vs. 16.7%; p<0.0001), and in the subgroups of patients with bystander CPR by family (19.4% vs. 13.4%;
p=0.001), with bystander CPR by unrelated persons (27.2% vs. 19.5%; p<0.0001), and with call-to-EMS arrival at the patient side
interval in three of four quartiles (quartile 1; 34.9% vs. 26.9%; p=0.03, quartile 2; 29.9% vs. 19.9%, p<0.0001, quartile 3; 21.0% vs.
13.3%, p=0.002). A multiple logistic-regression analysis showed that the adjusted odds ratio for a 30-day neurologically intact
survival after a 30:2 compression-ventilation ratio for CPR was 1.57 (95% CI, 1. 33 to 1.85, p<0.0001). Conclusions: Citizen-induced
CPR with a 30:2 compression-ventilation ratio is superior to that with a 15:2 compression-ventilation ratio in terms of neurological
benefit.
Guideline 8: CPR
49. Song F, Fosgerau K, Yu T, Weng Y, Chung S, Sun S, et al., Abstract 165: Trpv1 Agonist Rinvanil Induces Pharmacological
Hypothermia and Improves the Outcome of CPR in a Rat VF Model. Circulation 2010: 122(21_MeetingAbstracts);A165
Therapeutic hypothermia after resuscitation was recommended as a routine management by the AHA. However, the optimal cooling
method still remains to be investigated. Studies have demonstrated that TRPV1 agonist increases skin vasodilation and decreases
body temperature and reduces metabolism. In this study, we investigated the effects of TRPV1 receptor agonist Rinvanil on the
outcome in a rat model of CPR. We hypothesized that Rinvanil could induce hypothermia therefore improve survival. VF was induced
electrically in 10 male Sprague-Dawley rats and untreated for 6 mins. CPR was started 6 mins prior to defibrillation. Thirty mins after
31
Australian Research Council – November 2010 Research Updates
ROSC, animals were randomized to receive either saline vehicle or Rinvanil infusion. The starting dose of Rinvanil was 2.5 mg/kg/h.
Dosage was gradually increased to 15 mg/kg/h over 6 hours. The control animals received the same amount of saline. Temperature
and myocardial function were monitored for 6 hours and 7 day survival time was observed. Temperature decreased more than 2.5°C
with infusion of Rinvanil .Post resuscitation myocardial function was significantly better in the Rinvanil group than that in vehicle
group (P<0.05). Survival was improved in the Rinvanil group when compared with vehicle group (116±76hours vs 20±13hours,
P<0.05). TRPV1 receptor agonist Rinvanil induced hypothermia following ROSC and improved myocardial function as well as survival
in this rat model of CPR.
Guideline 11.8: Therapeutic hypothermia after cardiac arrest
50. Sun S, Weng Y, Song F, Yu T, Chung SP, Tang W, et al., Abstract 12102: Pharmacologically Induced Hypothermia with
Cannabinoid Receptor Agonist Improve the Outcome of Cardiopulmonary Resuscitation. Circulation 2010:
122(21_MeetingAbstracts);A12102
Early application of therapeutic hypothermia and rapid achievement of target cooling temperature are the key factors for improving
outcomes following CPR. Current available techniques for inducing hypothermia are either less effective or cumbersome for early
application. In this study, we investigated whether hypothermia could be induced pharmacologically following resuscitation with the
cannabinoid CB1/CB2 receptor agonist WIN55, 212–2 in a rat model of CPR. Our hypothesis was that when WIN55, 212–2 is
administered following resuscitation, it will reduce the body temperature and will therefore improve the outcome of CPR.
Ventricular fibrillation (VF) was induced in 10 Sprague-Dawley rats. CPR was initiated after 6 minutes of untreated VF. Defibrillation
was attempted after 8 minutes of CPR. Thirty minutes after resuscitation, animals were randomized to receive either WIN55, 212–2
(1.0 mg/kg/hr) or vehicle placebo (1.4 ml/kg/hr) as a control for 6 hours. Blood temperature was decreased from 37°C to 34°C four
hours after resuscitation progressively following infusion of WIN55, 212–2. Significantly better post-resuscitation myocardial
function and lower NDS (138 ± 106 vs 399 ± 199, p<0.05) were observed in the WIN55, 212–2 treated animals, and this was
associated with longer durations of survival (61 ± 15 vs 32 ± 23) compared with the control group. Therapeutic hypothermia
following CPR could be induced pharmacologically with a cannabinoid receptor agonist improving post-resuscitation myocardial and
cerebral functions, and duration of survival.
Guideline 11.8: Therapeutic hypothermia after cardiac arrest
32
Australian Research Council – November 2010 Research Updates
51. Teodorescu C, Reinier K, Dervan C, Uy-Evanado A, Samara M, Chugh H, et al., Abstract 18038: Morphology, Rate and Rhythm
of Ventricular Complexes during Primary PEA and their Prognostic Significance. Circulation 2010: 122(21_MeetingAbstracts);
A18038
Introduction: Sudden cardiac arrest (SCA) with pulseless electrical activity (PEA) has a significantly lower survival rate compared to
ventricular fibrillation and mechanisms of PEA are poorly understood. Hypothesis: We hypothesized that there is significant
variability in morphology, rate and rhythm of ventricular complexes recorded during PEA, with potential implications for
resuscitation outcome. Methods: In a pilot study from an ongoing community-based investigation of SCA in a metropolitan region of
the US Pacific Northwest (2002 –2009), recordings of primary PEA were analyzed from 51 consecutive subjects that underwent
resuscitation. Subjects were required to present with PEA as the initial rhythm. We measured morphology of the ventricular QRS
complex as well as rate and rhythm of the RR interval. Results: Overall mean R-R interval was 1697 ± 958 ms and the QRS duration
was 194 ± 115 ms. Slow PEA (R-R > 1000 ms) was observed in 41 (80%) of the recordings, fast PEA (R-R < 600 ms) in 4 (8%) and
normal R-R (600 – 1000 ms) PEA in 6 (12%). Wide complex PEA (QRS ≥ 120 ms) was found in 35 (69%) cases. Rhythm was irregular in
14 (27%). Fifteen cases (29%) had return of spontaneous circulation (ROSC) and 3 (6%) cases survived to hospital discharge (STHD).
Among slow PEA, ROSC was reported in 11 (27%) and STHD in 2 (5%). Among PEA with normal R-R, ROSC was observed in 4 (67%)
and STHD in one (17%). No patient with fast PEA had ROSC or STHD. Conclusions: The majority of primary PEA presents with a slow
rate <60 bpm and wide QRS complex. While further investigation is warranted in a larger study, fast PEA (rate>100) appears to have
the worst prognosis.
52. Tissier R, Chenoune M, Ghaleh B, Lidouren F, Darbera L, Dubois-Rande J-L, et al., Abstract 3: Hypothermic Total Liquid
Ventilation Improves Survival and Neurological Recovery Following Experimental Cardiac Arrest and Resumption of Spontaneous
Circulation in Rabbits. Circulation 2010: 122(21_MeetingAbstracts);A3
Introduction: Ultra-fast cooling using hypothermic total liquid ventilation (TLV) has been experimentally investigated for a
cardioprotective purpose or for the induction of intra-arrest hypothermia. Hypothesis: Our goal was to determine whether TLV also
improves survival and neurological recovery when instituted after resumption of spontaneous circulation (ROSC) following cardiac
arrest in rabbits. Methods: Ventricular fibrillation was induced in anesthetized rabbits. After 5 or 10-min of fibrillation (5' and 10'
groups, respectively), cardiopulmonary resuscitation was attempted. After ROSC, rabbits randomly underwent a normothermic
Control life support (conventional ventilation until weaning; Control-5' and Control-10' groups) or with rapid cooling (TLV-5' and TLV10' groups). In those last groups, a 32°C hypothermia was induced by 20-min of TLV. Hypothermia was further maintained under
conventional ventilation during 3h until rewarming and weaning. In all groups, hemodynamic and biochemical parameters were
monitored, as well as subsequent survival and neurological recovery. Neurological dysfunction was assessed by a 0–100% score
33
Australian Research Council – November 2010 Research Updates
system investigating reflexes, postural reactions and behaviour. After 7 days, survivors were finally euthanized for post-mortem
analyses. Results: ROSC was obtained in 10/10, 10/10, 7/10 and 7/10 rabbits in Control-5', TLV-5', Control-10' and TLV-10' groups,
respectively. In Controls, oesophageal and tympanic temperatures remained within 36.5 to 38.5°C throughout follow-up whereas
they achieved the 32–33°C target temperature in only ~10-min with no major adverse effect in TLV groups. Importantly, this rapid
cooling was associated with a dramatic improvement in subsequent survival and neurological recovery in TLV groups
Conclusions: Ultra-fast cooling instituted by TLV after ROSC improves survival and neurological recovery following experimental
cardiac arrest, p<0.05 vs Control.
53. Tsai M-S, Huang C-H, Tsai C-Y, Hsu C-Y, Chang W-T and Chen W-J, Abstract 11379: Intravenous Ascorbic Acid Administration
During Cardiopulmonary Resuscitation Reduces Mitochondrial Damage After Ventricular Fibrillation and Electrical Shock in a Rat
Model. Circulation 2010: 122(21_MeetingAbstracts);A11379
Background: Electrical shock (ES) generates free radicals inside the cardiomyocyte, causing contractile impairment, and
administering ascorbic acid (AA) reduces the damage. Intravenous administration of AA during CPR facilitates resuscitation and
improves outcomes in a rat model of VF. However, the effect of AA on the intracellular damage after VF and ES has not been
clarified. Hypothesis: Intravenous administration of ascorbic acid (AA) during CPR reduces mitochondrial damage after VF and ES.
Methods: The animals were equally randomized to AA, control and sham groups. In rats of AA group and control group, VF was
induced and untreated for 5 minutes, followed by 1 minutes of CPR, and then one electrical shock of 5 J. The AA group received
intravenous administration of AA (100 mg/kg) simultaneously at the start of CPR, and the control group received saline as placebo.
After ES, animals were sacrificed immediately. The sham group received the same treatments except VF induction, resuscitation,
drugs and ES. The mitochondria were isolated from left ventricles for measurement of mitochondrial permeability transition pore
(mPTP) opening and complex activity. Results: The Glomori stain showed that subsarcolemmal aggregation of mitochondria in the
control group, suggesting VF and ES resulted in mitochondrial damage. The application of AA alleviated the mitochondrial
aggregation. MPTP opening caused mitochondrial swelling. After adding CaCl2, the mitochondria of the control group showed
accelerated mitochondrial swelling. AA prevented the acceleration of mitochondrial swelling. Compared with the sham group, the
activity of NADH cytochrome c reductase (NCCR) and cytochrome c oxidase (CCO) but succinate cytochrome c reductase (SCCR)
decreased in the control group (Fig 1b-d) . AA prevented the decreased activity of NCCR and CCO after VF and ES.
Guideline 11.5: Medications in cardiac arrest
34
Australian Research Council – November 2010 Research Updates
54. Zwerus R, Andrade Ferreira I, Mooi B, Dambrink JH, van de Wetering H, Schutte M, et al., Abstract 17758: Incidence and
Predictors of Favourable Outcome 6 Months after an Out-of-Hospital Cardiac Arrest Treated with Hypothermia. Circulation 2010:
122(21_MeetingAbstracts); A17758
Background: There is a high mortality rate in patients presenting with an out-of-hospital cardiac arrest (OHCA). Although not fully
applied worldwide, Therapeutic Mild Hypothermia (TMH) is indicated to improve outcome for comatose survivors of an OHCA. The
objective of our study was to examine the value of TMH (therapeutic mild hypothermia) under different clinical circumstances and
to find predictors of a favourable patient outcome. Methods: This is a retrospective analysis covering January 2007 to June 2009 in
which 150 comatose patients post-OHCA were recorded. TMH to 32–34°C (endovascular cooling with CoolGard, for 24 hours) was
induced in all resuscitated OHCA patients. Patient outcome was recorded at hospital discharge and after 6–12 months using the
Pittsburgh Cerebral Performance Categories (CPC). A favourable outcome was defined as CPC score 1 or 2 at 6–12 months. Results:
Survival at hospital discharge and at 6–12 months FUP was 56.7% and 52.7% respectively. A favourable outcome at 6–12 months
was present in 96.2% of the patients who survived. Outcome was related to pre-defined variables such as initial heart rhythm, cause
of OHCA, characteristics during resuscitation and TMH. The most important differences between the favourable and unfavourable
outcome group were: age (59.0yrs vs. 68.2yrs, P<0.0001), initial rhythm VF (100% vs. 73%, P<0.0001), OHCA caused by non-cardiac
cause (1.3% vs. 12.2%, P<0.01). Conclusions: The large majority of OHCA survivors treated with TMH have a favourable neurological
outcome. Especially initial heart rhythm is strongly associated with outcome following an OHCA treated with TMH. None of the
patients with a Non-VF initial rhythm had a favourable neurological outcome. Therefore initial heart rhythm could contribute to
identify patients who benefit most from active induced cooling.
Guideline 11.8: Therapeutic hypothermia after cardiac arrest
REVIEWS
55. Chambers D, Paulden M, Paton F, Heirs M, Duffy S, Hunter JM, et al., Sugammadex for reversal of neuromuscular block after
rapid sequence intubation: a systematic review and economic assessment. Brit J Anaesth 2010: 105(5);568-75
Sugammadex 16 mg kg−1 can be used for the immediate reversal of neuromuscular block 3 min after administration of rocuronium
and could be used in place of succinylcholine for emergency intubation. We have systematically reviewed the efficacy and costeffectiveness and made an economic assessment of sugammadex for immediate reversal. The economic assessment investigated
whether sugammadex appears cost-effective under various assumptions about the value of any reduction in recovery time with
35
Australian Research Council – November 2010 Research Updates
sugammadex, the likelihood of a ‘can't intubate, can't ventilate’ (CICV) event, the age of the patient, and the length of the
procedure. Three trials were included in the efficacy review. Sugammadex administered 3 or 5 min after rocuronium produced
markedly faster recovery than placebo or spontaneous recovery from succinylcholine-induced block. No published economic
evaluations were found. Our economic analyses showed that sugammadex appears more cost-effective, where the value of any
reduction in recovery time is greater, where the reduction in mortality compared with succinylcholine is greater, and where the
patient is younger, for lower probabilities of a CICV event and for long procedures which do not require profound block throughout.
Because of the lack of evidence, the value of some parameters remains unknown, which makes it difficult to provide a definitive
assessment of the cost-effectiveness of sugammadex in practice. The use of sugammadex in combination with high-dose rocuronium
is efficacious. Further research is needed to clarify key parameters in the analysis and to allow a fuller economic assessment.
56. Harris T, Davenport R, Hurst T and Jones J, Improving outcome in severe trauma: trauma systems and initial management—
intubation, ventilation and resuscitation. Postgrad Med J 2010: Online first(1 Nov)
Severe trauma is an increasing global problem mainly affecting fit and healthy younger adults. Improvements in the entire pathway
of trauma care have led to improvements in outcome. Development of a regional trauma system based around a trauma centre is
associated with a 15–50% reduction in mortality. Trauma teams led by senior doctors provide better care. Although intuitively
advantageous, the involvement of doctors in the pre-hospital care of trauma patients currently lacks clear evidence of benefit. Poor
airway management is consistently identified as a cause of avoidable morbidity and mortality. Rapid sequence induction/intubation
is frequently indicated but the ideal drugs have yet to be identified. The benefits of cricoid pressure are not clear cut. Dogmas in the
management of pneumothoraces have been challenged: chest x-ray has a role in the diagnosis of tension pneumothoraces, needle
aspiration may be ineffective, and small pneumothoraces can be managed conservatively. Identification of significant haemorrhage
can be difficult and specific early resuscitation goals are not easily definable. A hypotensive approach may limit further bleeding but
could worsen significant brain injury. The ideal initial resuscitation fluid remains controversial. In appropriately selected patients
early aggressive blood product resuscitation is beneficial. Hypothermia can exacerbate bleeding and the benefit in traumatic brain
injury is not adequately studied for firm recommendations.
57. Jagoda A and Gupta K, The Emergency Department Evaluation of the Adult Patient Who Presents with a First-Time Seizure.
Emerg Med Clin N Am 2011: 29(1);41-9
Up to 5% of the population will experience at least 1 nonfebrile seizure at some point during their lifetime. The management of a
patient who has had a first-time seizure is driven by the history and physical examination. In almost one-half of these patients, the
cause of their seizure is not identified. In general, patients with comorbidities, a focal neurologic examination, or who have not
36
Australian Research Council – November 2010 Research Updates
returned to a normal baseline mental status require an extensive diagnostic evaluation including a noncontrast head computed
tomography (CT) scan in the emergency department (ED). Adults with a first-time seizure, with no comorbidities, and who have
returned to a normal baseline require only serum glucose and electrolyte determination. Women of reproductive age also require a
pregnancy test. Patients with a normal neurologic examination, normal laboratory results, and no signs of structural brain disease do
not require hospitalization or antiepileptic medications. Initiation of antiepileptic therapy depends on the assessed risk for
recurrence, in conjunction with a neurologist consultation.
Guideline 8.10: Seizures
58. Michael G and O’Connor R, The Diagnosis and Management of Seizures and Status Epilepticus in the Prehospital Setting.
Emerg Med Clin N Am 2011: 29(1);29-39
Seizure is one of the most common complaints encountered in the prehospital setting. In this review the authors discuss the
prehospital management of seizures and review the evidence for specific treatment approaches. Specific attention is devoted to
prehospital care of the pediatric seizure patient. Topics of interest to Emergency Medical Services directors such as patient refusal,
resource allocation, and dispatch priority are also addressed.
Guideline 8.10: Seizures
59. Pimentel L and Diegelmann L, Evaluation and Management of Acute Cervical Spine Trauma. Emerg Med Clin N Am 2010:
28(4);719-38
The evaluation and management of cervical spine injuries is a core component of the practice of emergency medicine. This article
focuses on evaluation and management of blunt cervical spine trauma by the emergency physician. Pertinent anatomy of the
cervical spine and specific cervical spine fractures are discussed, with an emphasis on unstable injuries and associated spinal cord
pathology. The association of vertebral artery injury with cervical spine fracture is addressed, followed by a review of the most
recent literature on prehospital care. Initial considerations in the emergency department, including cervical spine stabilization and
airway management, are reviewed. The most current recommendations for cervical spine imaging with regard to indications and
modalities are covered. Finally, emergency department management and disposition of patients with spinal cord injuries are
reviewed.
Guideline 8.18: Management of the potential spinal injury
37
Australian Research Council – November 2010 Research Updates
60. Robinett DA, Shelton B and Dyer KS, Special Considerations in Hazardous Materials Burns. J Emerg Med 2010: 39(5);544-53
Those practicing Emergency Medicine are frequently faced with a patient presenting with a chemical burn. Most dermal chemical
burns are minor and do not require specialized treatment. Occasionally, however, the clinician may be in the position of responding
to a chemical burn in which standard therapy of irrigation and good wound care may not be sufficient or, at worst, contraindicated.
Several burn conditions will be reviewed, some of those requiring only specific decontamination techniques, as in hot tar, others
posing special hazards to clinicians, as in elemental metals, and finally, examples are given of hazardous materials requiring
attention to systemic effects, as in hydrofluoric acid.
Guideline 8.5: Burns
ANIMAL / MANIKIN / CADAVER/ MODELS OF CARDIAC ARREST STUDIES
61. Brücken A, Kaab A, Kottmann K, Rossaint R, Nolte K, Weis J, et al., Reducing the duration of 100% oxygen ventilation in the
early reperfusion period after cardiopulmonary resuscitation decreases striatal brain damage. Resuscitation 2010: 81(12);1698703
Previous data indicate that 100% O2 ventilation during early reperfusion after cardiac arrest (CA) and cardiopulmonary resuscitation
(CPR) increases neuronal death. However, current guidelines encourage the use of 100% O2 during resuscitation and for an
undefined period thereafter. We retrospectively analyzed data from a porcine CA model and hypothesized that prolonged hyperoxic
reperfusion would be associated with increased neurohistopathological damage and impaired neurological recovery. Fifteen male
pigs underwent 8min of CA and 5min of CPR. After resuscitation animals were ventilated with either 100% oxygen for 60min
(hyperoxia; n=8) or 10min (normoxia; n=7). Physiological variables were obtained at baseline and 10, 60 and 240min after
resuscitation. Daily functional performance was assessed using an established neurocognitive test in parallel to a neurological deficit
score (NDS). On day 5, brains of the re-anaesthetized pigs were harvested for neurohistopathological analyses. At baseline there
were no differences in hemodynamics and neurological status between groups. Post-arrest only PaO2, as a result of the different
inspired oxygen fractions, was significantly higher in the hyperoxia group. There was a numerical trend towards improved clinical
recovery in both the NDS and the neurocognitive testing for animals exposed to 10min of 100% oxygen. However, hyperoxic animals
showed a significantly greater degree of necrotic neurons and perivascular inflammation in the striatum in comparison to normoxic
animals. In this retrospective analysis prolonged hyperoxia after CA aggravated necrotic brain damage and perivascular
inflammation in the striatum of pigs.
Guideline 11.7: Post-resuscitation therapy in ALS
38
Australian Research Council – November 2010 Research Updates
62. Haugk M, Krizanac D, Stratil P, Grassberger M, Weihs W, Testori C, et al., Comparison of surface cooling and invasive cooling
for rapid induction of mild therapeutic hypothermia in pigs—Effectiveness of two different devices. Resuscitation 2010:
81(12);1704-8
The effectiveness and safety of non-invasive surface cooling was compared to invasive endovascular cooling in an animal model.
Eight healthy pigs (29–38kg) were cooled twice, starting in the first 4 pigs with unique surface cooling pads followed by endovascular
cooling. In the second 4 pigs the order was reversed. The goal was to quickly lower pulmonary artery temperature from 38 to 33°C. A
paired t-test was used to compare cooling rates (°C/h, mean±standard deviation) between both cooling techniques. Mean noninvasive surface cooling rate (11.9±3.8°C/h) significantly exceeded mean invasive cooling rate (3.9±0.7°C/h; p<0.001). The mean
difference in cooling rates was 8.0±3.6°C/h. No surface cooling related adverse skin reactions were observed. Surface cooling is a
simple method for achieving fast cooling rates. In our animal model, non-invasive cooling was three times faster than rapid
endovascular cooling without overshoot.
Guideline 11.8: Therapeutic hypothermia after cardiac arrest
63. Lewis AR, Hodzovic I, Whelan J, Wilkes AR, Bowler I and Whitfield R, A paramedic study comparing the use of the Airtraq®,
Airway Scope and Macintosh laryngoscopes in simulated prehospital airway scenarios. Anaesthesia 2010: 65(12);1187-93
In a randomised, cross-over study, we compared the use of the Airtraq®, Airway Scope and Macintosh laryngoscopes by paramedics
for tracheal intubation in three simulated prehospital scenarios. Fifty-four paramedics were invited to take part. When evaluated in
a difficult airway manikin, median IQR [range] time to intubation with the Airtraq (21 (16–37 [6–80] s) and Airway Scope (16 (5–75
[12–23] s) was shorter than that with the Macintosh laryngoscope (39 (25–54 [7–120] s; p < 0.0001). The success rate within 30 s
was greater with the Airtraq (61%) and Airway Scope (93%) than with the Macintosh laryngoscope (22%; p < 0.0001). When used for
a standard intubation and in the sitting position, we found minimal differences among the three laryngoscopes. We conclude that
the Airway Scope and Airtraq have significant advantages over the Macintosh laryngoscope and that of the two, the Airway Scope is
the more effective device to use in the prehospital environment.
Guideline 11.6: Equipment & techniques in adult ALS
64. McMahon C, Kenny R, Bennett K, Little R and Kirkman E, The Effect of Acute Traumatic Brain Injury on the Performance of
Shock Index. J Trauma 2010: 69(5);1169-75
Background: Shock index (SI) is recognized to be a more reliable early indicator of hemorrhage than traditional vital signs. Acute
traumatic brain injury (TBI) can be associated with autonomic uncoupling and may therefore alter the reliability of SI in patients with
combined TBI and peripheral hemorrhage. The aim of this study was to evaluate the performance of SI (shock index) when acute TBI
39
Australian Research Council – November 2010 Research Updates
of mild and moderate severity were associated with progressive simple hemorrhage., Methods: This study was undertaken in a
laboratory setting. Brian injury was induced using the lateral fluid percussion model in anesthetized rats. The fluid percussion device
delivered an applied cortical pressure of 1.2 atm and 1.8 atm, producing mild and moderate TBI, respectively. Control animals
underwent identical procedures but with no applied cortical pressure. Hemorrhage was induced 10 minutes after brain injury, at a
rate of 2% of blood volume per minute until 40% blood volume was withdrawn., Results: The SI response to increasing volume of
hemorrhage was unaltered when control and mild TBI groups were compared (test of interaction p = 0.39). There was a 50%
mortality rate observed 20 to 60 minutes after hemorrhage in the moderate TBI group. The SI response to hemorrhage in the
moderate TBI group compared with the control group became significantly different at 40% blood volume loss (test of interaction p
= 0.048). Comparison of the SI response with hemorrhage between survivors and nonsurvivors of moderate TBI revealed a
significant difference (p = 0.007). SI was markedly attenuated in the presence of increasing hemorrhage in the nonsurvivor subgroup
of moderate TBI. Conclusions: SI significantly underestimated underlying hemorrhage in the presence of acute TBI of moderate
severity where attenuation of the biphasic heart rate and blood pressure response was also most pronounced.
65. Tracy MB, Klimek J, Coughtrey H, Shingde V, Ponnampalam G, Hinder M, et al., Mask leak in one-person mask ventilation
compared to two-person in newborn infant manikin study. Arch Dis Child Fetal Neonat 2010: Online first(11 Nov)
Aim: To compare a new two-person method (four hands) of delivering mask ventilation with a standard one-person method using
the Laerdal self-inflating bag (SIB) and the Neopuff (NP) infant resuscitator in a manikin model. Background: Recent studies of
simulated neonatal resuscitation using bag and mask ventilation techniques have shown facemask leak levels of 55–57% in expert
hands. Methods: 48 participants were randomly paired and instructed to give mask ventilation for a 2-min period as single-person
resuscitators, then as two-person paired resuscitators at set pressures for NP and set parameters for SIB. Airway pressure, flow,
inspiratory tidal volume, expiratory tidal volume and mask leak were recorded. Results: A total of 21 578 inflations were recorded
and analysed. For SIB, mask leak was greater (11.5%) with single-person compared to two-person (5.4%; mean difference 6.1%, 95%
CI 1.5 to 10.7, p<0.01). For NP, mask leak was greater for single-person (22.2%) compared to two-person (9.1%; mean difference
13.1% 95% CI 3.6 to 22.6, p<0.01). For single-person mask ventilation, mask leak was greater with NP (22.2%) compared to SIB
(11.5%; mean difference 10.7%, 95% CI 1.4 to 19.7, p<0.01). For two-person mask ventilation, mask leak was greater for NP (9.1%)
compared to SIB (5.4%; mean difference 3.7%, 95% CI 0.1 to 6.4, p<0.05). Conclusions: Two-person mask ventilation technique
reduces mask leak by approximately 50% compared to the standard one-person mask ventilation method. NP mask ventilation has
higher mask leak than Laerdal SIB for both single- and two-person technique mask ventilation.
Guideline 13.4: Airway management and mask ventilation of the newborn infant
40
Australian Research Council – November 2010 Research Updates
CASE SERIES / CASE STUDIES/ LETTERS/EDITORIALS
66. Barelli A and Scapigliati A, The four-stage approach to teaching skills: The end of a dogma? Resuscitation 2010: 81(12);1607-8
Traditionally, physicians and nurses have gained motor skills through experience alone instead of being taught formally with
evidence-based educational techniques. However, opportunities for clinical training are becoming restricted because of higher
numbers of students, limited resources, stricter ethical guidance, etc. Furthermore, teachers and students prioritise skills teaching
differently: 11th versus 5th respectively in a list of educational topics. These factors have resulted in the creation of alternate
strategies for skills training. Procedural skill teaching theories have evolved substantially over the last two decades. We have moved
from the old adage of “seeing one, doing one and teaching one” through the three-stage theory of motor skills acquisition to the
more recent four-stage approach. The four-stage approach breaks down the skills teaching process into four steps (demonstration,
deconstruction, formulation, performance). By following these stages, the trainee shifts from being ‘consciously incompetent’
(realising he can’t do it) to being ‘consciously competent’ (being able to do it with great thought)....
Section 9: Instruction
67. Berger E, Nothing Gold Can Stay?: EMS Crashes, Lack of Evidence Bring the Golden Hour Concept Under New Scrutiny. Ann
Emerg Med 2010: 56(5);A17-A9
On a steamy Harlem morning last July, an Acura blasted its radio while approaching the intersection of 125th Street and Seventh
Avenue. As a result, the car's driver did not hear the sirens of an oncoming ambulance and broadsided the emergency vehicle, which
was responding to a call in haste. Reacting to the Acura, the ambulance swerved and crashed into a city bus and Ford Expedition.
Nineteen people were injured, requiring the services of several more ambulances........a reevaluation of speed at all costs in
delivering patients to the hospital—has gained ground in recent years as scientists have stepped up their investigations into the
notion of a “golden hour,” the time-honored idea that patients have the best chance of surviving a traumatic injury if they receive
medical care within 60 minutes. In several studies, scientists have accumulated a growing amount of evidence that time does not
always matter when it comes to traumatic injuries. The golden hour, it seems, stands on a foundation of less than rigorous scientific
evidence. The concept is most widely credited to famed trauma surgeon R. Adams Cowley, a pioneer in emergency medicine who
spearheaded the creation of the nation's first statewide EMS system in Maryland. Cowley originated the idea on a cocktail napkin in
a Baltimore bar,......
41
Australian Research Council – November 2010 Research Updates
68. Dami F, Fuchs V and Yersin B, The dispatcher's window. Resuscitation 2010: 81(12);1735
The primary mission of emergency dispatch centres was originally to respond quickly to all calls, to identify the location of the victim
and dispatch adequate rescue vehicles and personnel to the site as soon as possible. Over the last 20 years, additional procedures
known as ‘life-saving manoeuvres’ have been developed which include dispatchers proposing emergency measures to bystanders
calling in. This has not only increased significantly the skills and responsibilities of emergency medical dispatchers but, more
importantly, it has contributed to reduced mortality, particularly in cases of sudden cardiac arrest. In order to further enhance the
effectiveness of emergency measures, the concept of the ‘bystander’s window’ was born. It suggests that the presence of a
bystander may dramatically change the fate of a victim. However, the vital role a dispatcher plays during this critical period is not
highlighted by this term...
69. Haines DE, Automated External Defibrillators and the Law of Unintended Consequences. JAMA 2010: 304(19);2178-9
Sudden cardiac arrest remains a significant public health problem. Successful resuscitation from tachyarrhythmic cardiac arrest
increases if time to defibrillation is reduced. Therefore, early detection of life-threatening arrhythmias followed by rapid initiation of
effective therapy has been the goal. Patients requiring hospitalization benefit from being admitted to a facility where special
resuscitation equipment and trained personnel are in close proximity around the clock. The benefits of rapid resuscitation led to the
proliferation of coronary care units in the 1960s and 1970s, even though the cost-effectiveness of these units was difficult to
demonstrate. A natural assumption promoted by thought leaders was that institution of electrocardiographic (ECG) telemetry
monitoring on hospital wards could improve outcomes by expanding early arrhythmia detection and treatment to locations beyond
intensive care units. This compelling goal fueled the billion-dollar medical telemetry industry, despite limited well-designed scientific
studies proving its value. In fact, despite . . .
Guideline 7: Automated external defibrillators in BLS
70. Hommers C, Oxygen therapy post-cardiac arrest: The ‘Goldilocks’ principle? Resuscitation 2010: 81(12);1605-6
The disappointingly low survival rate following cardiac arrest has recently shifted focus from interventions that improve success of
cardiopulmonary resuscitation (CPR) to factors that may modify outcome favourably after return of spontaneous circulation (ROSC).
Whilst early restoration of blood flow to ischaemic tissues is essential to halt progression of cellular damage, it is now clear that
reperfusion initiates a complex series of reactions that paradoxically injure tissues. This global ischaemic/reperfusion (IR) response is
responsible for the post-cardiac arrest syndrome observed in survivors of cardiac arrest. The brain is particularly vulnerable to IR and
post-cardiac arrest brain injury is a common cause of death and disability. Following the success of therapeutic hypothermia, the
search for interventions that may improve outcome meaningfully has recently focused on the high concentrations
42
Australian Research Council – November 2010 Research Updates
of oxygen routinely administered during CPR and for prolonged periods after reperfusion. Whilst concerns about the use of 100%
oxygen are not new, the appropriateness of this standard practice after resuscitation has been questioned by growing experimental
and emerging clinical data....
Guideline 11.7: Post-resuscitation therapy in adult ALS
71. Miraj A, Foaud A and Seth B, Cardiac arrest following an anaphylactic reaction to atracurium. BMJ Case Reports 2010: Online
first(5 Nov)
This report describes a life-threatening anaphylactic reaction in a 58-year-old woman who was scheduled for subacromial
decompression of right shoulder joint. She had a modified rapid sequence induction using fentanyl 100 µg, propofol 150 mg and
suxamethonium 100 mg. Following induction her blood pressure and pulse were stable. On return of spontaneous ventilation, she
had intravenous administration of 30 mg of atracurium. Soon after, she developed profound bradycardia followed by a cardiac
arrest. Cardiopulmonary resuscitation (CPR) commenced with 100% oxygen and intravenous administration of atropine 3 mg and
epinephrine 1 mg. After 1 min of CPR she had the return of spontaneous circulation with a blood pressure of 160/100 mm Hg. Her
sedation was maintained using minimal isoflurane until the return of spontaneous ventilation to avoid awareness. Surgery was
postponed. Later she made an uneventful recovery. Her serum tryptase level was raised and a positive intradermal reaction to
atracurium confirmed atracurium anaphylaxis.
72. Murugiah K and Rajput K, Cardiopulmonary resuscitation (CPR) survival rates and Internet search for CPR: Is there a relation?
Resuscitation 2010: 81(12);1733-4
There is immense regional variability in survival rates for out-of hospital cardiac arrest (OHCA). Less than 50 communities have
reported their experience and one can only speculate outcomes in other regions. There are many outcome predictors following
OHCA, such as the speed with which the chain of survival links are initiated, post-resuscitative care, socio-economic/racial
composition of the community, etc. Factors such as cardiopulmonary resuscitation (CPR) awareness, variation in initiatives toward
CPR training, and willingness to provide CPR also probably play a role. The Internet is an important source of health information for
patients and physicians alike....
73. O’Connor CJ, Avoidance of endobronchial intubation. BMJ 2010: 341(Online first);9 Nov
Endotracheal intubation is commonly performed to secure the airway in a variety of clinical settings, including prehospital and
emergency room settings; the intensive care unit; and, most commonly, the operating room. Endobronchial intubation as a
complication of endotracheal intubation can cause atelectasis and hypoxaemia, as well as potential hyperinflation and barotrauma
43
Australian Research Council – November 2010 Research Updates
of the intubated lung. Although several methods are currently available to identify oesophageal intubation, only chest radiography
and bronchoscopy can reliably detect endobronchial intubation, and effective bedside techniques to detect this complication are
needed..….Accidental endobronchial intubation occurs in about 5% of patients in intensive care, 28% of those with a cardiac arrest,2
3 and 10% of out of hospital endotracheal intubations. In the Australian Incident …
74. Parotto M, Doglioni N, Micaglio M, Zanardo V, Perilongo G and Trevisanuto D, Efficacy of the neonatal resuscitation program
(NRP) course on knowledge retained by residents: Comparison among pediatrics, anesthesia and gynecology. Resuscitation 2010:
81(12);1741-2
Neonatal resuscitation is a mandatory role for all the delivery room professionals, including midwives, nurses and physicians from
different specialties (pediatrics, anesthesiology and gynecology). However, the background training of the various health care
providers presents important differences, which may require different strategies for the teaching of neonatal resuscitation
fundamentals. The Neonatal Resuscitation Program (NRP), a widely adopted training program endorsed by the American Heart
Association (AHA) and the American Academy of Pediatrics (AAP), has shown to provide good retention of knowledge in the
participants, but information regarding its efficacy in relation to the specialty training of the attendants is lacking. We evaluated the
effectiveness of the NRP course in the knowledge gained by third year pediatrics, anesthesiology and gynecology residents in our
centre...
Guideline 9.1.1: CPR training Section 13: Neonatal guidelines
EDUCATION / ETHICS
75. Cheng J, Yan Z, Zhiqiao C, Sheng C and Xiaobo Y, Improving cardiopulmonary resuscitation in the emergency department by
real-time video recording and regular feedback learning. Resuscitation 2010: 81(12);1664-9
Improvement in the quality of cardiopulmonary resuscitation (CPR) may improve the survival rate following cardiac arrest. The aims
of our study were to describe how recording of CPR maneuvers performed in our emergency department with real-time video and
regular feedback learning may improve CPR. A digital video-recording system enabled us to record and analyze CPR procedures for
adult patients from March 2007 to July 2008. Our resuscitation teams received video-recording feedback learning every week. We
analyzed 45 cases, divided into three groups of 15 consecutive patients. Instantaneous rates of chest compression showed variation
with 75% exceeding 110cpm. There was a significant difference in instantaneous rates among groups (135 [112–150] in group 1, 123
[110–136] in group 2 and 124 [111–137]cpm in group 3, P<0.001). Ratio of hands-off time to total manual compression time (%)
significantly decreased over time (Spearman correlation=−0.30, P=0.04). There were significant differences in hands-off time per
44
Australian Research Council – November 2010 Research Updates
minute among the groups (11 [3–28], 6 [2–21] and 7 [2–19]smin−1, P<0.001). There was a significant improvement in time delay to
first chest compression (11 [5–50], 20 [8–68] and 0 [0–12]s, P=0.01), but not in time delay to first ventilation (91 [31–190], 65 [17–
121] and 24 [9–64]s, P=0.08). Data are median [25–75% interquartile]. Regular feedback learning from real-time video recording may
improve the quality of major CPR variables.
Guideline 9.1.1: CPR training
76. Orde S, Celenza A and Pinder M, A randomised trial comparing a 4-stage to 2-stage teaching technique for laryngeal mask
insertion. Resuscitation 2010: 81(12);1687-91
To compare the ‘4-stage’ teaching technique (demonstration, deconstruction, formulation, performance) with the traditional ‘2stage’ teaching technique (deconstruction, performance) in laryngeal mask airway (LMA) insertion. Using a prospective randomised
study design, participants were taught LMA insertion on a manikin by either the ‘2-stage’ or ‘4-stage’ teaching method. Subjects
were eligible if they had never inserted a LMA. Skill acquisition was assessed immediately following training, and skill retention
assessed a number of weeks later. The primary outcome was LMA insertion on a manikin, with successful ventilation within 30s.
Other outcomes included overall time to LMA insertion, and number of errors. Assessors were blinded to the teaching method used
for each subject. A total of 120 participants were randomised between the two teaching groups (60 subjects in each group). Mean
time to LMA insertion at acquisition was 39.7s for 2-stage and 34.7s for 4-stage (p>0.05), and proportion completing within 30s was
41.67% for 2-stage and 48.33% for the 4-stage teaching group (p>0.05). With skill retention assessment, mean time to LMA insertion
was 44.3s for 2-stage and 42.5s for the 4-stage teaching group (p>0.05). Proportion completing task within 30s was 34.0% for 2stage and 41.67% for 4-stage group (p>0.05). Overall, there was no significant difference found in skill acquisition or in skill retention
between the 2 or 4-stage teaching method. The 2-stage teaching technique is not statistically different to the 4-stage teaching
method in efficacy of LMA insertion skill acquisition or retention.
Guideline 9.1.1: CPR training
77. Pasquale MA, Pasquale M, Baga L, Eid S, Leske J, Brywczynski J, et al., Family Presence During Trauma Resuscitation: Ready
for Primetime? J Trauma 2010: 69(5);1154-60
Background: The concept of family presence during trauma resuscitation (FPTR) remains controversial. Healthcare providers have
expressed concern that resuscitation of severely injured trauma patients is inappropriate for family members as they may have
psychologic distress, disrupt resuscitative efforts, or misinterpret provider actions, which can ultimately impact satisfaction with
care. The minimal evidence that exists is descriptive or anecdotal., Methods: Using a previously developed FPTR protocol, a
prospective, comparative study assessing 50 adult family members, who were present (n = 25) or not present (n = 25) with their
45
Australian Research Council – November 2010 Research Updates
severely injured adult family member during resuscitation, was conducted. Family member anxiety was assessed using State-Trait
Anxiety Inventory, satisfaction using a Revised-Critical Care Family Needs Inventory, and well-being using Family Member Well-being
Index within 48 hours of intensive care unit admission. Mean total scores were compared for both groups with independent t tests.
Significance was set at p < 0.05. Results: Age and Injury Severity Score were statistically equivalent in all patients. Anxiety,
satisfaction, and well-being were not statistically different in family members present compared with those not present during
resuscitation. There were no untoward events during resuscitation efforts. Family members present felt they benefited the patient
and gained a better understanding of the situation. Conversely, family members not present commented that they would have
preferred to have been present during resuscitation. Conclusions: Family members present during trauma resuscitation suffered no
ill psychologic effects and scored equivalent to those family members who were not present on anxiety, satisfaction, and well-being
measures. Quality of care during trauma resuscitation was maintained. The fact that all the family members would repeat
experience again supports the idea that FPTR was not too traumatic for those who chose to be present.
Guideline 10.5: Legal and ethical issues
78. Weiner S, Kapadia T, Fayanju O and Goetz J, Socioeconomic disparities in the knowledge of basic life support techniques.
Resuscitation 2010: 81(12);1652-6
Substantial disparities exist in health measures between different socioeconomic groups, including mortality. We hypothesized that
a difference in knowledge of life-saving basic life support (BLS) techniques between groups may also contribute. A 34-question
survey was administered to a convenience sample of patients 18 and older presenting to an urban ED in Boston. Patients who were
intoxicated, prisoners, critically or mentally ill, had an insurmountable language barrier or victims of abuse were excluded. Trained
research assistants collected the data. An inactivated automated external defibrillator (AED) device was utilized to test identification
of the device and its correct usage. 440 patients were considered for inclusion. 163 patients met exclusion criteria, leaving 277
eligible patients. 59 patients refused, and 218 patients (78.7%) completed the survey instrument. Overall, 144 (66.7% (95% CI 60.1–
72.6%)) felt confident recognizing the signs of a heart attack. 93 (42.9% (95% CI 36.5–49.5%)) recognized that heart attack symptoms
were different in men and women. 112 (51.3% (95% CI 44.8–57.9%)) were trained to do CPR. Patients were more likely to be trained
in CPR if English is their first language (OR 2.25 (1.18–4.28) p=0.012) or if they earned >$40,000 per year (OR 2.15 (1.17–3.95)
p=0.013). Recognition of the AED was more common in those who completed college (OR 2.70 (1.52–4.78) p=0.0005), were white
(OR 1.78 (1.03–3.08) p=0.036), had English as the 1st language (OR 3.33 (1.63–6.81) p=0.0005), earned >$40,000 per year (OR 3.21
(1.70–6.06) p=0.0002) or had private insurance (OR 2.32 (1.33–4.04) p=0.003). Demonstration of correct usage of the AED was more
common in patients who completed college (OR 1.91 (1.09–3.32) p=0.022) and had private insurance (OR 2.19 (1.26–3.82) p=0.005).
No differences were detected between the genders, age > or < than 50, or patients who have a PCP. Multiple socioeconomic
46
Australian Research Council – November 2010 Research Updates
disparities exist in the knowledge of BLS techniques. This study describes these disparities, and presents an opportunity to target
education and potentially reduce mortality for these specific groups.
AND….JUST IMAGINE HOW MUCH THE NEW ‘SINUSOIDAL-MOTION’ AMBULANCE STRETCHERS WILL COST…….
Jorge IB, Heng W, Jaqueline A, Paul K and Jose AA, Whole Body Periodic Acceleration (pGz) Improves Survival and Allows for
Resuscitation in a Model of Severe Hemorrhagic Shock in Pigs. The Journal of Surgical Research 2010: 164(2);e281-e9
Whole body periodic acceleration (pGz), the repetitive, head-foot sinusoidal motion of the body, increases pulsatile shear stress on
the vascular endothelium producing increased release of endothelial derived nitric oxide (eNO) into circulation. Based upon prior
CPR investigations, we hypothesized that pGz instituted prior to and during hemorrhagic shock (HS) should improve survival. Sixteen
anesthetized male pigs, 23 ± 5 kg, were randomized to receive 1 h pGz or no pGz (CONT) prior to and during severe controlled
graded HS up to 2-1/2 h. HS was induced by removing blood at 10 mL/kg increments from the circulation at 30-min intervals up to a
maximum blood loss of 50 mL/kg. Thirty minutes after maximum blood loss, shed blood and lactated Ringers solution was infused
intravenously. All animals survived up to 30 mL/kg blood loss. Survival and return to normal blood pressure to 120 min was achieved
in 50% of animals receiving pGz compared with none in CONT. Cardiac output, blood pressure, and oxygen delivery decreased
equally in both groups but oxygen consumption was significantly lower with pGz than CONT during all hemorrhage time points.
Regional blood flow (RBF) was preserved in brain, heart, kidneys, ileum, and stomach in both groups up to 40 mL/kg of blood loss.
After 40 mL/kg blood loss, RBF was much better preserved in pGz than CONT. pGz applied 1 h prior to and during severe graded
hemorrhagic shock delays onset of irreversible shock, enabling potential restoration of blood loss and survival.
47
Australian Research Council – November 2010 Research Updates