Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
STUDY OF PLACING A SECOND INTRAVENOUS LINE IN TRAUMA Mark A. Merlin, DO, Emily Kaplan, MD, Jeffrey Schlogl, MD, Heather Suss, MD, Frank D. DosSantos, DO, Pamela Ohman-Strickland, PhD, Adam Shiroff, MD is modeled after the Advanced Trauma Life Support (ATLS) course. An additional IV line, in a trauma setting, is placed to protect against the potential loss of intravascular volume. However, only small percentages of trauma patients present with hemodynamic instability and require aggressive fluid resuscitation for improved outcome.2 Studies have demonstrated that internal hemorrhage may be worsened by aggressive resuscitation when a mean arterial pressure (MAP) of 60–80 mmHg is chosen for the resuscitation endpoint.3–6 Aggressive fluid management may result in a number of undesired complications, which include lowering the patient’s body temperature to a point of hypothermia, dilution of essential coagulation factors, and the emergence of visceral swelling with pulmonary edema. Capone et al. studied fluid resuscitation in rats with uncontrolled hemorrhage and demonstrated frequent coagulopathy and rebleeding if resuscitated too aggressively.7 In addition, prehospital IV lines have been demonstrated to increase on-scene times with subsequent worsened outcomes.8–10 Aside from the detrimental effects of aggressive fluid management, practical reasons for avoiding placement of a second IV line exist. Obtaining IV access in the prehospital arena is especially difficult in a moving ambulance. This level of difficulty can be detrimental to the patient, potentially resulting in a vascular or nerve injury while attempting to place a second line.11 Additional IV lines also increase the chance of accidental needlestick to the emergency medical services (EMS) provider as well as the possibility of introducing bacteria into the patient.11 This study was conducted to evaluate the effect of placement of one versus two IV lines on the endpoints of heart rate, blood pressure, volume of fluid infused, pulse oximetry, mental status (Glasgow Coma Scale [GCS] score), rehospitalization rate, and 30-day mortality. Furthermore, we hypothesized that patients who received additional IV fluids would have no difference in these endpoints. Heart rate, systolic blood pressure, and diastolic blood pressure were measured both at the scene (prior to IV fluids) of the emergency and on arrival in the emergency department (ED) (after IV fluids). Injury Severity Score (ISS) was used to verify that the patients in the two groups had experienced similar injuries. ABSTRACT Objective. We evaluated the benefit of emergency medical services providers’ placing a second intravenous (IV) line in the prehospital trauma setting. Our hypothesis was that the placement of a second IV catheter in trauma does not result in an improvement in heart rate, blood pressure, rehospitalizaton rate, or 30-day mortality. Methods. A retrospective chart review of 320 trauma patients in a one-year period was conducted at our level I trauma center. All trauma patients who had vascular access obtained prehospitally were included. Results. Patients with two IV lines received an average of 348.4 mL more fluid (95% confidence interval [CI]: 235.6, 461.1; p < 0.0001). No change in heart rate, pulse oximetry, Glasgow Coma Scale score, systolic blood pressure, rehospitalization rate, or 30-day mortality was noted. These effects persisted for patients who were initially tachycardic (heart rate 3.92 bpm; 95% CI –3.01, 10.82; p = 0.27) or hypotensive (blood pressure 22.00 mmHg; 95% CI −4.17, 48.16; p = 0.10). Conclusions. Redundant prehospital IV lines provided no noticeable benefit in physiologic support for trauma patients. When controlling for confounding variables, no significant outcome difference was noted, even in the hypotensive patients. The traditional approach for establishment of a secondary IV line in prehospital trauma patients should not be followed in a dogmatic fashion. Key words: emergency medical services; intravenous; trauma; ambulance; prehospital PREHOSPITAL EMERGENCY CARE 2011;15:1–6 INTRODUCTION According to Prehospital Trauma Life Support (PHTLS) guidelines, it is standard of care to provide every trauma patient with two large-bore intravenous (IV) lines in the prehospital setting.1 This curriculum Received January 28, 2010, from the Department of Emergency Medicine (MAM), Robert Wood Johnson Medical School, New Brunswick, New Jersey; and the Departments of Medical Education (EK, JS, HS, FDDosS), Public Health (PO-S), and Surgery (AS), University of Medicine and Dentistry of New Jersey–Robert Wood Johnson Medical School, New Brunswick, New Jersey. Revision received October 16, 2010; accepted for publication October 18, 2010. Address correspondence and reprint requests to: Mark A. Merlin, DO, Robert Wood Johnson Medical School, Emergency Medicine, 1 Robert Wood Johnson Place, MEB 104, New Brunswick, NJ 08901. e-mail: [email protected] doi: 10.3109/10903127.2010.545612 1 2 PREHOSPITAL EMERGENCY CARE APRIL/JUNE 2011 VOLUME 15 / NUMBER 2 FIGURE 1. State trauma triage criteria. ALS = advanced life support; AVPU = alert, verbal, painful, unresponsive; BP = blood pressure. METHODS This was a retrospective cohort study. It was approved by our university’s institutional review board, which has a subcontract with our hospital. A chart review was performed on 320 patients who were evaluated between May 1, 2008, and April 30, 2009. The search terms “trauma” and “IV attempt” were used in our electronic medical record (EMR) (www.emscharts.com, West Mifflin, PA) to select our initial patient population. The inclusion criteria were all trauma patients who received IV access in the prehospital setting. Patients were identified as trauma vic- tims by our prehospital providers if they met state trauma guidelines (Fig. 1). This database was crossreferenced with the ED database, Sunrise Clinical Manager (SCM) (Eclipsys Corporations, Atlanta, GA). Information for ISSs was obtained upon arrival of patients to our trauma center. Rehospitalization rates and 30-day mortality data were obtained by research associates who called the individual household phone numbers given upon arrival to our trauma center. This study was conducted at an American College of Surgeons (ACS)-verified level I trauma center. Our trauma volume is approximately 1,500 patients per year, with 18% having experienced Merlin et al. 3 TWO IVS IN TRAUMA TABLE 1. Summaries of Raw Data Variable Age, years Gender —female Any fluids Volume of fluids, mL GCS score at 15 GCS score Heart rate, bpm Systolic blood pressure, mmHg Diastolic blood pressure, mmHg Pulse oximetry Time (If Applicable) On-scene Arrival On-scene Arrival Change On-scene Arrival Change On-scene Arrival Change On-scene Arrival Change Overall (N = 236) No. Missing (% of Total) 3 2 5 5 8 22 3 22 23 2 3 4 7 7 12 25 16 30 53 (1%) (1%) (2%) (2%) (3%) (9%) (1%) (9%) (10%) (1%) (1%) (2%) (3%) (3%) (5%) (11%) (7%) (13%) (22%) All Mean (±SD) or n (% of Observed) 37.3 47 75 174.7 157 156 13.6 13.6 0.0 93.9 90.5 –3.6 131.8 133.3 0.7 81.1 79.3 –2.3 98.7% ( ± 19.3) (20%) (32%) ( ± 422.6) (69%) (73%) ( ± 3.1) ( ± 3.4) ( ± 1.6) ( ± 20.5) ( ± 17.9) ( ± 9.3) (22.3) ( ± 23.5) ( ± 19.3) ( ± 15.3) ( ± 14.2) ( ± 17.5) ( ± 1.9%) One IV Line Mean (±SD) or n (% of Observed) 37.6 38 44 76.7 116 114 13.8 13.7 –0.1 93.9 90.7 –3.5 132.5 132.6 0.3 82.0 78.9 –3.2 98.7% ( ± 20.0) (23%) (27%) ( ± 187.7) (72%) (76%) ( ± 3.0) ( ± 3.4) ( ± 1.5) ( ± 21.9) ( ± 18.9) ( ± 9.6) (21.0) ( ± 23.1) ( ± 19.5) ( ± 14.1) ( ± 13.0) ( ± 14.0) ( ± 2.0%) Two IV Lines Mean (±SD) or n (% of Observed) 36.5 9 31 425.1 41 42 13.2 13.3 0.2 93.8 90.1 –3.7 130.1 135.1 1.6 78.9 80.5 0.2 98.6% ( ± 17.5) (14%) (48%) ( ± 679.9) (62%) (67%) ( ± 3.4) ( ± 3.4) ( ± 1.9) ( ± 16.8) ( ± 16.0) (8.8) (25.3) ( ± 24.3) ( ± 18.9) ( ± 17.8) ( ± 17.0) ( ± 24.2) ( ± 1.6%) p-Value for One versus Two 0.68 0.15 0.0020 0.0001 0.16 0.19 0.19 0.51 0.28 0.98 0.81 0.90 0.51 0.48 0.62 0.23 0.49 0.32 0.81 GCS = Glasgow Coma Scale; IV = intravenous; SD = standard deviation. penetrating trauma. The county population of approximately 800,000 residents is made up of 68.4% white, 13.9% Asian, 13.6% Hispanic, and 9.1% African American residents. The county occupies 323 square miles with a combination of urban cities and suburban communities. Our EMS system covers 85% of the county. In the county, there are five acute care hospitals and three advanced life support (ALS)-providing agencies. All trauma patients in the region who meet state criteria are brought to our level I trauma center (Fig. 1). The EMS system is two tiered, composed of a combination of paid and volunteer basic life support (BLS) units and paid hospital-based ALS units that contain two paramedics each. There are eight BLS units and six ALS units that respond to approximately 30,000 dispatches per year, 6,500 of these being patients treated by ALS in the system. Our state paramedic protocols for trauma patients recommend placement of two IV lines prehospitally. However, paramedics insert the second IV line with variability based on time to the hospital, subjective determination of the patient’s degree of illness, and difficulty obtaining the IV placement. In critical patients when an IV line cannot be started, the paramedics are allowed to use an intraosseous needle. The decision to place the second IV line or to use the intraosseous needle is made by the paramedics at the scene. An investigator trained in Microsoft Access (Microsoft Corp., Redmond, WA) and the Emergency Department Information Management (EDIM) database collected all data. Patient care reports (PCRs) generated on a laptop computer during the course of patient interactions were transferred to a Microsoft Access database after completion. Statistical analysis was carried out utilizing SAS 9.1 TS level 1M0, XP PRO platform (SAS Institute Inc., Cary, NC) and MINITAB 15 (MINITAB Inc., State College, PA). Summaries of all covariates and outcomes are presented in Table 1, means and standard deviations for continuous variables and numbers and frequencies for categorical variables. p-Values are given for differences between groups, based on observed data. Table 2 contains the estimated unadjusted and adjusted differences in means between listed outcomes for patients with one versus two IV lines as well as the regression model for volume of infused fluid. Sensitivity analyses were conducted when evaluating outcomes measured as changes from on-scene time to arrival at the trauma center, such that only subjects who had low GCS scores (less than 15), low systolic or diastolic blood pressure (less than the median), or high heart rate (greater than the median) were included in each set of appropriate analyses. Only subjects who had these low GCS scores, low systolic and diastolic blood pressure, or high heart rate were included, resulting in parametric data. The cutoff values of blood pressure and heart rate were made based on current literature and the authors’ clinical experience.1,12 Systolic and diastolic blood pressures as well as heart rates were normally distributed both on scene and on arrival. In addition, changes in these measures were normally distributed. The distribution of GCS scores was highly right skewed, whereas the distribution of pulse oximetry values was highly left skewed at both time points; however, changes were unimodal and symmetrical. The distributions of these changes were light tailed; methods used for analysis were robust and not expected to be influenced by these light tails, 4 PREHOSPITAL EMERGENCY CARE APRIL/JUNE 2011 VOLUME 15 / NUMBER 2 TABLE 2. Estimated Difference in Adjusted and Unadjusted Means (Confidence Intervals and p-Values for Testing No Difference) between Subjects with One and Two Intravenous Lines Variable Pulse oximetry, % Volume of fluids, mL Change in GCS score All subjects GCS score <15 on scene Change in heart rate, bpm All subjects HR >100 bpm on scene Change in systolic BP, mmHg All subjects Systolic BP <132 mmHg on scene Systolic BP <100 mmHg on scene Change in diastolic BP, mmHg All subjects Diastolic BP <80 mmHg on scene Diastolic BP <60 mmHg on scene Unadjusted Adjusted for Age, Gender, and Whether below Median on Scene (When Appropriate) –0.05 (–0.64, 0.54) 0.87 348.4 (235.6, 461.1) < 0.0001 –0.10 (–0.69, 0.49) 0.74 357.2 (224.1, 470.4) < 0.0001 Adjusted for Age, Gender, Whether below Median on Scene (When Appropriate), and Volume of Fluids 0.20 (–0.45, 0.84) 0.55 – 0.29 (–0.17, 0.74) 0.22 0.72 (–0.60, 2.04) 0.29 0.28 (–0.19, 0.74) 0.24 0.73 (–0.64, 2.11) 0.30 0.34 (–0.18, 0.86) 0.21 0.91 (–0.68, 2.51) 0.26 –0.21 (–2.89, 2.46) 0.88 2.65 (–3.55, 8.86) 0.64 0.40 (–2.13, 2.92) 0.76 2.88 (–3.27, 9.02) 0.36 0.87 (–1.94, 3.67) 0.54 3.92 (–3.01, 10.86) 0.27 3.42 (–2.10, 8.94) 0.22 4.26 (–3.24, 11.75) 0.27 4.30 (–13.71, 22.31) 0.64 4.34 (–1.09, 9.77) 0.12 5.41 (–2.08, 12.89) 0.16 2.50 (–18.59, 23.58) 0.82 2.93 (–2.83, 8.69) 0.32 2.55 (–5.86, 10.97) 0.55 22.00 (–4.17, 48.16) 0.10 5.32 (1.02, 9.62) 0.015 8.18 (2.16, 14.19) 0.0077 13.47 (–7.43, 34.37) 0.21 5.27 (1.10, 9.45) 0.013 8.58 (2.79, 14.37) 0.0037 6.86 (–20.41, 34.13) 0.62 5.41 (0.76, 10.07) 0.023 9.89 (3.38, 16.40) 0.0029 31.63 (2.20, 61.05) 0.035 BP = blood pressure; GCS = Glasgow Coma Scale; HR = heart rate. particularly with the moderately large sample sizes used. Correlations between outcome measures were also calculated. Based solely on observed data, differences between patients with one versus two IV lines were assessed using either Pearson chi-square tests or twogroup t-tests allowing for unequal variances, with a Satterthwaite method for estimating the appropriate degrees of freedom.13,14 Regression models estimated the unadjusted effects of the number of IV lines as well as the effects adjusted for age and gender; when appropriate (for GCS score, heart rate, systolic blood pressure, and diastolic blood pressure), whether the patient was above or below the median and the previously listed covariates; and the volume of fluids infused. Estimates, confidence intervals (CIs), and p-values are given for these unadjusted and adjusted effects of number of IV lines on changes in GCS score, heart rate, systolic blood pressure, and diastolic blood pressure from on-scene to arrival time points as well as pulse oximetry and volume of fluids. In addition, regression models estimated the effects of volume of infused fluids, unadjusted and adjusted for age and gender as well as, when appropriate (for GCS, heart rate, systolic blood pressure, and diastolic blood pressure), whether the person was above or below the median on a particular outcome on scene. In these regression analyses, multiple imputation was used to account for the small amount of missing data.15,16 The above analyses were repeated for individuals. The ISS means were compared between the groups using differences of means and rates of rehospitalization and 30-day mortality using differences of proportions. RESULTS From these analyses, we determined that the effect of number of IV lines was even larger (8.18 mmHg; 95% CI: 2.16, 14.19; p = 0.0077) when considering only patients who had low diastolic blood pressures when their on-scene care began. Also, patients with elevated heart rates (greater than 100 bpm) did not benefit from the additional IV fluids (3.92 bpm; 95% CI; –3.01, 10.86; p = 0.27), nor did the patients with low systolic blood pressures (<100 mmHg). Volumes of fluids differed significantly between the numbers of IV lines. Those with two IV lines received on average of 348.4 mL more fluids (95% CI: 235.6, 461.1; p < 0.0001). Change in diastolic blood pressure showed a significant difference between patients with one versus two IV lines, an average of 5.32-mmHg greater increase (95% CI: 1.02, 9.62; p = 0.015) than that for patients with only one IV line. The difference persisted after adjusting for covariates, including the volume of fluids infused. This effect persisted with diastolic blood pressures below 60 mmHg. No other outcomes significantly differed between patients with one versus two IV lines. No differences were found in ISS between the two groups (15.609 in those with one IV line versus 18.806 in those with two IV lines; p = 0.1255). No differences were found in rehospitalization rates (9.7% in those with one IV line versus 9.2% in those with two IV lines [46 of 76 patients contacted had one IV line versus 30 of 76 patients contacted had two IV lines]) or 30-day patient mortality (8.1% in those with one IV line versus 8.2% in those with two IV lines [same patient information obtained]). Follow-up was based on only 23% of patients who were able to be contacted. Merlin et al. 5 TWO IVS IN TRAUMA DISCUSSION Standards of care in the prehospital setting need to be constantly reevaluated. We sought to evaluate the utility of placing a second IV line in trauma patients on the endpoints of blood pressure, heart rate, GCS score, rehospitalization rate, and 30-day mortality. As in all protocols, risks versus benefit must be weighed to determine the utility of maintaining a practice. Since most trauma patients are treated with a sense of urgency, the potential risk of needlestick is increased. In addition, IV lines increase on-scene times while worsening outcomes. Significant literature exists questioning the standard practice of aggressive fluid management in the prehospital and hospital settings.17–21 This is the first study in the literature to evaluate the placement of one versus two IV lines in this arena. We demonstrated changes in both the volume of fluid infused and the diastolic blood pressure for those patients who received a second IV line. While a statistically significant difference in diastolic blood pressure was found, the cause of this difference is difficult to determine. It is possible that another unaccounted-for variable caused the diastolic blood pressure to rise, independent of the underlying condition. It is also possible that patients’ blood pressures would have been lower if they had not received any IV fluids. The difference in heart rate, as a potentially sensitive marker of low volume states, was consistently not significant between the patients who received one versus two IV lines. Most importantly, for tachycardic patients, the extra fluid did not yield improvement in vital signs. This finding persisted in hypotensive patients. Since this is the most sensitive endpoint of volume status in our study, it provides the best evidence that additional fluid difference is not altering vital signs on heart rate. LIMITATIONS AND FUTURE RESEARCH There are limitations to our study. This was a singleinstitution study at one of three level I trauma centers in our state and, therefore, extrapolations can be made only to similar settings. The data entered by the prehospital care providers may have had some slight inaccuracies. The information obtained from the Access databases was entered during emergency situations when time was limited and, therefore, could potentially contain reporting errors. Some discrepancies were identified when matching patients between databases, including errors in spelling and dates. The data were thoroughly reviewed to identify these errors, but the possibility exists that not all errors were detected. Additionally, this study was conducted retrospectively. Therefore, no cause-and-effect relationships could be established. Although associations were found between patient treatment groups, there exists the possibility that these may be due to confounding variables. Our endpoints represented data points that were easily accessible and standard; however, vital signs vary based on medical conditions, medications such as atrioventricular (AV) nodal blockers, diseases of the vascular system, and fitness levels. Blood pressure in particular is not known to be a very sensitive marker of volume status until later stages of shock. Additionally, blood pressures vary between health care providers taking the measurements, calibration of machines, and general margins of error of the sphygmomanometer. A significant number of patients were lost to follow-up. Approximately 50% did not provide correct phone numbers or provided numbers that were disconnected. Another 23% did not return our phone calls after multiple messages were left. It is possible that mortality and rehospitalization rate would yield different results based on improved follow-up. Also, it is possible that patients who responded to follow-up were less severely injured than the rest of the population. We attempted to review all records in our system to verify that the patients did not return to our regional trauma center. Future research should evaluate how the placement of no IV line compares with the placement of one and two IV lines. It was extremely rare for patient in our study population to have no prehospital peripheral access, so it was not possible for us to entertain this hypothesis. CONCLUSION Redundant prehospital IV lines provided no difference in physiologic outcomes for trauma patients. When controlling for confounding variables, no significant outcome difference of heart rate or volume infused was noted, even in the hypotensive patients. The traditional approach for establishment of a secondary IV line in prehospital trauma patients should not be followed in a dogmatic fashion. References 1. American College of Surgeons. Prehospital Trauma Life Support Manual, 6th edition. St. Louis, MO: Mosby, 2006. 2. Cannon WB, Fraser F, Cowell EM. The preventative treatment of wound shock. JAMA. 1918;47:618–21. 3. Capone AC, Safar P, Stezoski W, Tisherman S, Peitzman AB. Improved outcome with fluid restriction in treatment of uncontrolled hemorrhagic shock. J Am Coll Surg. 1995;180:49–56. 4. Marshall HP Jr, Capone A, Courcoulas AP, et al. Effects of hemodilution on long-term survival in an uncontrolled hemorrhagic shock model in rats. J Trauma. 1997;43:673–9. 5. Burris D, Rhee P, Kaufmann C, et al. Controlled resuscitation for uncontrolled hemorrhagic shock. J Trauma. 1999;46:216–23. 6 6. Bickell WH, Wall MJ Jr, Pepe PE, et al. Immediate versus delayed fluid resuscitation for hypotensive patients with penetrating torso injuries. N Engl J Med. 1994;331:1105–9. 7. Capone A, Safar P, Stezoski SW, Peitzman A, Tisherman S. Uncontrolled hemorrhagic shock outcome model in rats. Resuscitation. 1995;29:143–52. 8. Seamon MJ, Fisher CA, Gaughan J, et al. Prehospital procedures before emergency department thoracotomy: “scoop and run” saves lives. J Trauma. 2007;63:113–20. 9. Birk HO, Henriksen LO. Prehospital interventions: on-scene time and ambulance-technicians’ experience. Prehosp Disaster Med. 2002;17:167–9. 10. O’Gorman M, Trabulsy P, Pilcher DB. Zero-time prehospital IV. J Trauma. 1989;29:84–6. 11. Bhananker SM, Liau DW, Kooner PK, et al. Liability related to peripheral venous and arterial catheterization: a closed claims analysis. Anesth Analg. 2009;109:124–9. 12. Edwards M, Ley E, Mirocha J, Hadjibashi AA, Margulies DR, Salim A. Defining hypotension in moderate to severely injured trauma patients. Am Surgeon. 2010;76:1035– 8. 13. Satterthwaite FE. An approximate distribution of estimates of variance components. Biometric Bull. 1946;2:110–4. PREHOSPITAL EMERGENCY CARE APRIL/JUNE 2011 VOLUME 15 / NUMBER 2 14. Neter J, Wasserman W, Kutner MH. Applied Linear Statistical Models. Burr Ridge, IL: Richard D. Irwin, Inc., 1990. 15. Little RJA, Rubin DB. Statistical Analysis with Missing Data. Hoboken, NJ: J. Wiley & Sons, 1987. 16. Rubin DB. Inference and missing data. Biometrika. 1976;63:581–92. 17. Owens TM, Watson WC, Prough DS, Uchida T, Kramer GC. Limiting initial resuscitation of uncontrolled hemorrhage reduces internal bleeding and subsequent volume requirements. J Trauma. 1995;39:200–7. 18. Hein LG, Albrecht M, Dworschak M, Frey L, Bruckner UB. Long-term observation following traumatic-hemorrhagic shock in the dog: a comparison of crystalloidal vs. colloidal fluids. Circ Shock. 1988;26:353–64. 19. Krausz MM, Hirsh M. Bolus versus continuous fluid resuscitation and splenectomy for treatment of uncontrolled hemorrhagic shock after massive splenic injury. J Trauma. 2003;55:62–8. 20. Kreimeier U, Prueckner S, Peter K. Permissive hypotension. Schweiz Med Wochenschr. 2000;130:1516–24. 21. Solomonov E, Hirsh M, Yahiya A, Krausz MM. The effect of vigorous fluid resuscitation in uncontrolled hemorrhagic shock after massive splenic injury. Crit Care Med. 2000;28:749–54.