Download Developing a Perioperative Sleep Apnea Safety Program

Developing a Perioperative Sleep
Apnea Safety Program
Wm. Charles Sherrill, Jr M.D.
Sleep Program Medical Director
Presbyterian Sleep Health – Novant
Carolina Sleep Society
May 5, 2012
OSA and the Surgical Patient
• Conflict of Interest:
– None
Clinical Scenario
• A 32 year old presented for an open reduction and internal
fixation of an arm fracture, which was satisfactorily
performed under general anesthesia. He was discharged to
the ward on a fentanyl PCA (pt controlled analgesia) with a
25mcg bolus, 12-minute delay, and 25mcg hourly rate.
• At night, the nurses heard him snoring loudly. One hour
after his last normal vital signs, he was found in respiratory
arrest. He was resuscitated, but displayed signs of anoxic
brain damage.
• By questioning the patient’s wife, a consultant was able to
elicit the husband’s history of heavy snoring and nocturnal
apneic spells that were felt to be clinically consistent with a
diagnosis of sleep apnea.
Ann Lofsky, M.D. Sleep Apnea and Narcotic Postoperative Pain Medication: A Morbidity
and Mortality Risk
Clinical Scenario
• 45 year old male, 320 lbs and 5’11” had a rotator cuff repair
under general anesthesia. The intraoperative course was
uneventful. He was admitted to the ward for overnight pain
control.
• Four hours after surgery, he received an intramuscular
injection of Meperidine 100 mg with Phenergan 25 mg. This
was repeated 3 hours later when severe pain prevented
him from sleeping.
• Two hours later, nurses making a routine check found him
to be in full arrest. He could not be resuscitated. The
internist’s history and physical mentioned his having been
diagnosed with sleep apnea.
Ann Lofsky. M.D. Sleep Apnea and Narcotic Postoperative Pain Medication: A Morbidity and
Mortality Risk
OSA and the Surgical Patient
• Malpractice cases involving Obstructive Sleep
Apnea in Hospitalized Patients
• Intubation complications (20%)
• Extubation difficulties (10%)
• Post operative catastrophes (70%)
– Drug induced respiratory arrest resulting in death/brain
damage
– Patients with OSA with inadequate monitoring
OSA and the Surgical Patient
• Postoperative catastrophes (“Dead in bed”)
– Severe OSA
– Morbid obesity
– Isolated ward room
– No monitoring
– Receiving narcotics
– Off O2/PAP
Jonathan L. Benumof, M.D.
OSA and the Surgical Patient
• The pharynx is a hollow potentially collapsible tube
without rigid fixed bony structures for support and
surrounded entirely by soft tissue.
• Patency is dependent on
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Intrinsic mechanical stiffness of the airway
Upper airway muscle activity
Extraluminal pressure
Lung volume
• The imbalance of these forces is critical to the
development of upper airway obstruction
The Balance of Forces
(Malhotra & White, 2002)
OSA and the Surgical Patient
• Individuals with OSA are primarily dependent on the
activity of the pharyngeal dilator muscles for airway
patency.
– OSA patients demonstrate increased EMG activity in the
pharyngeal dilator muscles (Genioglossus muscle) during
wakefulness.
– The reduction in EMG activity in these muscles at sleep
onset is greater in OSA patients than normals.
– OSA patients have a reduced ability to compensate for
factors that predispose them for upper airway collapse
• Increased negative pharyngeal pressures during inspiration
• Reductions in upper airway muscle tone
OSA and the Surgical Patient
• Physiologic factors in OSA which could result
in increased perioperative complications
– Anatomical imbalance
– Lung volume reduction (Decreased FRC and ERV)
– Sympathetic nervous system activation
– Ventilatory instability (loop gain)
OSA and the Surgical Patient
• Impact of sedatives, anesthetics, and analgesics
(opioids) on respiratory function
• Dose dependent depression of muscle activity of the
upper airway muscles
– Depression of central respiratory output/upper airway
reflexes
» Increased collapsibility of the upper airway
– Direct action (peripheral) on hypoglossal (tongue) and phrenic
(diaphragm) nerves
» Phrenic nerve depression – decreases in lung volume
– Alterations in apneic threshold/hypoxic sensitivity
– Alterations in the chemical/metabolic/behavioral
control of breathing
OSA and the Surgical Patient
• Increase in sympathetic nervous system activation
(catecholamine excess)
– Surgical stress
– Hpoxemia/Hypercarbia
– Arousals
• Related to an increased risk of cardiac arrhythmias,
cardiac ischemia and hypertension .
• Majority of unexpected and unexplained postoperative
deaths occur at night and within 7 days of surgery.
Rosenberg, J. et al British Journal of Surgery 1992.
OSA and the Surgical Patient
Postoperative factors which may contribute to
complications in OSA
– Use of neuraxial / parenteral opioids
– Positioning
– Sleep fragmentation / REM rebound (?)
– Comorbid medical conditions
OSA and the Surgical Patient
• What is the scope of the problem?
• How does the surgical process affect
individuals with obstructive sleep apnea?
• Does OSA result in postoperative
complications more frequently than the nonOSA surgical population?
OSA and the Surgical Patient
• What is the prevalence of obstructive sleep apnea in
the general surgical population?
– Data obtained primarily from screening questionnaires.
– Results would suggest that 25%-30% of patients presenting
for elective general surgery would screen positive for OSA.
• Is this going to be less of a problem or more of a
problem in the future?
Obesity Trends* Among U.S. Adults
BRFSS, 1990, 1998, 2007
(*BMI 30, or about 30 lbs. overweight for 5’4” person)
1990
1998
2007
No Data
<10%
10%–14%
15%–19%
20%–24%
25%–29%
≥30%
OSA and the Surgical Patient
• Critical points of the NHANES data
– Prevalence of clinically severe obesity is increasing much faster than
that of moderate obesity.
Strum, R. Increase in morbid obesity in the USA. Public Health 2007,
121(7), 492-496. Data from 2000-2005.
– BMI > 40 kg/m2 has increased fivefold
– 1:200 adults to 1:33 adults
– BMI > 50kg/m2 has increased tenfold
– 1:2,000 adults to 1:200 adults
• More not less of these individuals will be showing up for surgical
intervention.
OSA and the Surgical Patient
• The STOP-BANG Questionnaire Identified the
Patients with Significant Exacerbations of Sleep
Disordered Breathing during the Perioperative
Period. P. Liao et al.
– 67 patients: STOP-BANG + limited channel testing
• 20 low risk (SB < 3); 47 high risk (SB >3)
• High Risk patients
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Pre operative AHI 10.2/hr.
PON 1
AHI 13.2/hr.
PON 3
AHI 23.2/hr.
PON 5
AHI 17.9/hr.
PON 7
AHI 16.0/hr.
• STOP-BANG 6-8 predictive of patients with higher AHI
OSA and the Surgical Patient
• Does the presence of obstructive sleep apnea
place patients at increased risk for postoperative
complications?
– Respiratory or cardiovascular difficulties
– Transfer to higher level of care acuity
– Increased length of hospital stay
– Mortality
OSA and the Surgical Patient
• Kaw, R. et al. AJRCCM 183; 2011: A3147
– IM preop assessment and PSG databases
crossmatched to identify patients underwent both
PSG and non cardiac surgery.
• 1784 pts , 471 pts eligible for study: 269 (57%) had OSA
• Presence of OSA associated with:
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Increased incidence of significant hypoxia (p=0.02)
Reintubation (p=0.048)
Unplanned ICU transfer (OR=7.6)
Overall complications (OR=9.9)
Longer length of hospital stay (OR=1.9)
OSA and the Surgical Patient
• Postoperative complications
– Higher reintubation rates
(+)/(-)
– Hypoxemia / Hypercarbia
(+)
– Arrhythmias
– Myocardial ischemia
– Increased transfers to higher level of care (+)/(-)
– Increased length of hospitalization (+)/(-)
– Delirium
– Reationship to severity of OSA (AHI) (+) / (-)
OSA and the Surgical Patient
• Prevalence of obstructive sleep apnea appears to be
increasing in association with the increase in obesity. The
prevalence of both known and unknown obstructive sleep
apnea in the surgical population will be increasing in the
future.
• These patients are at increased risk for postoperative
complications and death that may be reduced with
appropriate screening and post operative monitoring.
OSA and the Surgical Patient
• OSA patients will present for surgery in one of three
ways:
– Known OSA compliant with therapy
– Known OSA
• Mild OSA – therapy not recommended
• Refused therapy or non compliant
• Therapy instituted – weight loss, surgery, dental appliance: status
unknown
– Unrecognized OSA
• Goal: Minimize the number of these patients presenting for
surgery
– Goal: Provide appropriate monitoring and access to post
operative evaluation; if needed longitundinal care.
OSA and the Surgical Patient
• Know moderate/severe OSA on therapy:
– Primary focus: assess status
• Compliance with therapy
• Resolution of symptoms
• Development of comorbid conditions
• Continue PAP therapy postoperatively
– Pressure requirements may increase postoperatively
Bolden, N. et al. Anesthesia Analgesia 2007, 105; 7867-7870.
OSA and the Surgical Patient
• Known OSA – no active therapy
– Asymptomatic or minimally symptomatic
– May become symptomatic postoperatively
• Gupta et al. study. Complication rate not related to
severity of OSA
• Unrecognized / Non-compliant
– These surgical patients are the primary focus of
perioperative sleep apnea safety program
OSA and the Surgical Patient
• Clinical management strategy
– Preoperative Screening (Identification)
– Monitoring (Keeping the patient safe)
– Discharge (Longitudinal evaluation and care)
OSA and the Surgical Patient
• Why do we need a mechanism for screening?
– F. Chung ASA 2010 Oct A773
– 819 pts: 234 pts in lab PSG; 585 pts HST
– Surgeons/anesthesiologists not informed of PSG
results. Clinical diagnosis of OSA noted by record
review.
– 138/819 pts had severe OSA (AHI > 30) (17%)
• 118/138 (86%) were not identified by surgeons
• 65/138 (47.1%) were not identified by anesthesia
OSA and the Surgical Patient
• Purpose of OSA Screening (Identification)
– Eliminate or markedly reduce the unrecognized OSA patient
presenting for surgery
– Heightened awareness of which patients may be at increased
postoperative risk
– Opportunity to identify poorly compliant or inadequately
treated patients and intervene
– Limitation: Screening does not discriminate between mild and
moderate/severe OSA. Does not identify true “at risk” patients.
OSA and the Surgical Patient
• Questions to ask: Perioperative Sleep Apnea Program
– How do you screen patients preoperatively?
– What do you do with patients that screen positive?
– How do you monitor these patients?
– How and when do you treat patients that screen positive?
– What happens after discharge?
OSA and the Surgical Patient
• Screening Questionnaires
– Berlin Questionnaire
– ASA Checklist
– STOP and STOP-BANG questionnaire
– Sleep Apnea Clinical Score (SACS) (Flemons)
Screening Tools for OSA
• Important features:
– Easy to understand
– Ease of administration/scoring
– Limited time requirements
– Sensitivity/Specificity
– Validated (PSG)
– Generalizable to various patient populations
• Primary care, surgical, medical, sleep clinic
OSA and the Surgical Patient
Validation of the Berlin Questionnaire and
American Anesthesiologists Checklist as
Screening Tools for OSA in Surgical Patients.
Chung, F. et al. Anesthesiology V 108 No 5 May 2008, 822-830.
Preoperative pts 18 yrs or older and without
previously diagnosed OSA.
2,467 patients were screened:
OSA and the Surgical Patient
• Classified as high risk of OSA
– Berlin Questionnaire
– ASA Checklist
– STOP Questionnaire
33%
27%
28%
• No significant difference in the questionnaires
in the ability to identify patients with OSA.
• Approximately 30% of general surgical
patients will screen positive for OSA.
OSA and the Surgical Patient
• Sensitivity (STOP-BANG Questionnaire)
– AHI>5
– AHI>15
– AHI>30
STOP 65.6% STOP-BANG 83.6%
STOP 74.3% STOP-BANG 92.9%
STOP 79.5% STOP-BANG 100%
• Negative Predictive Value (NPV)
– AHI>5
– AHI>15
– AHI>30
STOP 44.0% STOP-BANG 60.8%
STOP 76.0% STOP-BANG 90.2%
STOP 89.3% STOP-BANG 100%
OSA and the Surgical Patient
• Data suggests that the use of screening questionnaires
can reliably identify patients at risk for obstructive
sleep apnea.
– Sensitivity and negative predictive value good. Specificity
fair
– False positive rate is 15%-20%.
– Majority that screen positive will have mild obstructive
sleep apnea.
• Roughly 50% mild OSA; 33% mod/severe OSA; 13% severe OSA
– Use of any of the screening tools improves the likelihood
of identifying obstructive sleep apnea.
OSA and the Surgical Patient
• A Higher Score on STOP-BANG was Associated with a
Higher Incidence of Post-Operative Complications. F.
Chung, P. Liao
– STOP-BANG and overnight HST (10 channel)
– 862 patients completed STOP-BANG/complication
– STOP-BANG
• 0-2 postoperative complication
39.9%
• 3-5
54.3%
• 6-8
66.1%
– Both cardiac and pulmonary complications increased with
increasing score; not neurologic
– Argues for use of higher STOP-BANG score to assess risk
– U of Chicago: STOP-BANG greater than or equal 5.
OSA and the Surgical Patient
• Screen positive for Obstructive Sleep Apnea. Now
what?
– Monitor high risk patients perioperatively
Intervene with PAP therapy for cardiopulmonary difficulties.
Evaluation and definitive therapy after discharge.
– Evaluate and institute therapy prior to surgery.
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Who does the consultation?
Choice of diagnostic study.
Who do you treat?
Mode of treatment?
Process has to be completed in a timely fashion.
OSA and the Surgical Patient
• Consultation:
– Sleep physician
– Physician extender
– “Super nurse”
• Antic, N.A. Am J Respir Crit Care Med vol 179. p 501-508,
2009
– Sleep technician/Respiratory therapist/ Sleep
navigator
– Template: symptoms, comorbid conditions, physical
exam
OSA and the Surgical Patient
• Diagnostic testing:
– In lab polysomnography
– Limited channel testing (portable sleep testing)
– Autonomic measures of sleep disordered
breathing
• Peripheral arterial tone (PAT)
• Cardiopulmonary coupling (CPC)
OSA and the Surgical Patient
• Decision if made to treat who do you treat:
– Level of AHI / ODI
• Increased risk of complications with increasing AHI. (not
seen in all studies)
– Invasiveness of surgery / post operative narcotic
requirements (used to determine risk in ASA
guidelines)
– Patients that experience arrhythmias, ischemia, oxgen
desaturation postoperatively (PACU)
– Presence and severity of comorbid conditions
OSA and the Surgical Patient
• Treatment Preoperatively
– CPAP/Bilevel based on titration study
– Auto-titrating pressure therapy
– Time constraints for compliance
• Potential benefit of preoperative PAP therapy
– Reduction in upper airway edema
– Improved PAP compliance during hospitalization ?
• Mayo experience: APAP use in high risk patients
– POD 1 median APAP use 396 minutes
– Length of stay median APAP use 213 minutes
OSA and the Surgical Patient
• Postoperative monitoring
– Who should be monitored?
– What level of monitoring is appropriate?
– Where should the monitoring take place?
– How long should monitoring be continued?
OSA and the Surgical Patient
• Monitoring based on:
– Level of AHI / ODI / SpO2 nadir
– Invasiveness of surgery and postoperative narcotic
requirements
– Clinical course in PACU
– Presence of comorbid conditions
OSA and the Surgical Patient
• Sleep-Disordered Breathing in Hospital Patients:
Identifying and Treating Ptients at Risk. Gay, P.
– Use of Sleep Apnea Clincal Score (SACS) to screen
– 693 patients non cardiac surgery
– Likelihood of postoperative respiratory events
• High SACS: OR 3.5
• Recurrent events in PACU: OR 21
– Course in PACU apppears to be most predictive of
subsequent postoperative respiratory events.
OSA and the Surgical Patient
• Monitoring Postoperatively
– Level of care (ward, step down unit, ICU)
– Monitoring in room and central
– Type of monitoring
• Oximetry, ECG
• Oximetry, ECG plus capnography
– Duration of monitoring
• Time: First 24 hours
• During use of narcotics postoperatively
• Ability to maintain SaO2 > 90 % room air (with sleep?)
OSA and the Surgical Patient
• Monitoring in the postoperative period with
oximetry alone or oximetry with capnography
No studies which have demonstrated superiority of
either monitoring strategy in:
Reduction in postoperative complications
Reduced length of stay
Reduction in transfers to higher level of acuity
of care.
Nonrandomized studies in individual institutions have
suggested reductions in complications and reductions
in transfers to higher levels of care with monitoring.
OSA and the Surgical Patient
• Recommendations for monitoring
– Use of oximetry in high risk patients
– Continuation of monitoring until able to maintain oxygen
saturation > 90% on room air including a period of sleep
(definition of sleep)
– Role of capnography needs to be defined
– Action plan / protocol for response to alarms
– Future: Integrated monitoring systems
OSA and the Surgical Patient
• Post operative management
– Multimodality pain management
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NSAID’s
Acetominophen
Tramadol
Ketamine
Gabapentin/Pregabalin
Clonidine
Dexamethasone
Dexmedetomidine (Precedex)
– Alpha 2 agonist
– Post operative oxygen desaturation 12-14 times more likely in
OSA patients receiving opioid analgesia compared with nonopioid analgesia.
• Bolden, N. et al. Anesth Analg 2008; 105: 1869-70.
OSA and the Surgical Patient
• Law of unintended consequences:
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Monitoring capability / Costs
Logistics/flow process
Increased utilization and costs of PAP therapy
Increased demand for RCP services
Education
• New technology i.e. capnography
• New terms: AHI, ODI etc
• New skill sets
– False alarms: “alarm fatigue”
– False sense of security
OSA and the Surgical Patient
• CoMorbidities: should they be considered in the assessment of
level of monitoring?
– Higher Risk:
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Atrial fibrillation*
Congestive heart failure*
Severe COPD
Coronary artery disease*
Obesity Hypoventilation Syndrome
Pulmonary Hypertension Kaw, R. Respiratory Medicine 2011, 105, 619-624
Uncontrolled Hypertension*
– Lower Risk:
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Mild COPD
Hypertension
Diabetes Mellitus
Cerebrovascular disease*
Obesity BMI > 35 kg/m2*
OSA and the Surgical Patient
• What should you do?
– Minimum:
• Screen preoperatively
• Those that screen positive – special identification
• Notification to primary care physician upon discharge
of positive screen.
OSA and the Surgical Patient
• What should you do?
– Maximum
• Screen preoperatively
• Those that screen positive: evaluation and those with
moderate/severe OSA: treatment.
– Evaluation: consultation; in lab and/or limited channel testing
– Treatment: in lab titration and/or APAP.
• Monitoring post operatively with use of PAP with sleep
• Discharge: Notification of primary care physician
Follow up with sleep physician for longitudinal care
STOP-BANG > 5
Screen OHS
Known OSA
(AHI >15)
Known Mild OSA
(AHI 5-15)
Suspected OSA
(+ Screen)
PAP Post-Op
PACU
(-)
PACU
(+)
PACU
(+)
PACU
(-)
Monitor
Usual
Care
Monitor
APAP
Monitor
Monitor
Usual
Care
D/C Monitor SpO2
Usual
Care
> 90% during Sleep
D/C Home
on PAP
PACU (+)
Desaturation
Apnea
Hypoventilation
Discharge
Higher Level of Acuity
Moderate/Severe OSA
PACU (+)
Co-morbid Conditions
D/C on APAP
Sleep Consultation
Discharge
OSA and the Surgical Patient
• Intolerant/Noncompliant with PAP therapy
– Behavioral therapy
• Elevate Head of bed / Minimize supine position
• Minimize narcotics / sedatives
– O2 with sleep to maintain oxygen saturation > 90%
– Discharge on O2
– Follow up sleep consultation (out-patient)
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Evaluation / Diagnostic testing
CPAP Clinic
Desensitization therapy
Discussion of alternative therapies for OSA
OSA and the Surgical Patient
• Discharge recommendations
– Establishment of protocols which ensure that
individuals identified at high risk for OSA are
referred for appropriate evaluation, treatment,
and longitudinal care when appropriate.
– Patients discharged on APAP if used during
hospitalization.
– Expedited referral for patients in which PAP
therapy was initiated during hospitalization.
OSA and the Surgical Patient
• Things to come?
– Case Western Reserve University
• Dennis Auckley, M.D.
• 311 in-patients admitted to general medicine floor
during 4 month period.
– Assessed both STOP-BANG and Berlin Questionnaire
» 60.2 % positive both screens
» 81.8 % no diagnosis of OSA
» 40.2 % received IV narcotics
» No orders for respiratory monitoring
OSA and the Surgical Patient
• Things to come?
– Continuous Positive Airway Pressure: Evaluation of
a Novel Therapy for Patients with Acute Ischemic
Stroke.
• Bravata, D. et al. Sleep Vol 34 No 9, 2011, 1271-1277.
• Pts with acute ischemic stroke use of APAP to diagnose
and treat OSA compared with control group.
• Improvements in Stroke Scale in CPAP group compared
with controls.
– Utilization in high risk medical patients.
Sleep Management Center
• Inpatient Sleep Apnea Consultation
– Opportunity to identify previously undiagnosed
patients with OSA
– Reduce postoperative complications/death
– Establish longitudinal care to reduce long term
cardiovascular risk.
– Patients with comorbidities most often will
require in lab diagnosis and treatment.
OSA and the Surgical Patient
• Future Challenges
– Identification of “true” at risk patients
• Higher cutoff for positive questionnaires
• Presence of co-morbid conditions: OHS / pulmonary HTN
– Optimum and prudent monitoring strategy
• Threshold alarms
– Improvement in compliance with therapy during hospitalization
– Process to improve patients evaluation and institution of therapy.
(50% rule).
– Expansion of program to other high risk hospitalized medical patients
• In patient sleep consultative services
• Questions: [email protected]
OSA and the Surgical Patient
• Algorithms
– Sleep and Sleep-Disordered Breathing in the Hospitalized
Patient. Peter Gay, M.D. Respiratory Care Sept 2010, Vol 55, No
9, 1240-1254.
– Management of Sleep Apnea in Adults-Functional Algorithm for
the Perioperative Period. Chung, F. M.D. Can J Anesthesia 2010,
57: 849-864.
– Perioperative Management of OSA Patients: Practical Solutions
and Care Strategies. UCSD/University of Toronto.
– Perioperative Management of Obstructive Sleep Apnea.
Adesanya, A. et. al. Chest 2010; 138(6) 1489-1498.
– Advoiding Adverse Outcomes in Patients with Obstructive Sleep
Apnea (OSA): Development and Implementation of a
Perioperative OSA Protocol. Bolden, N. et. al. Jr Clin Anesthesia
2009, 21, 286-293.