Post-operative Complications in Patients with Obstructive Sleep Apnea Eleni Giannouli, MD, FRCPC, ABIM (Sleep)

Transcription

1 Post-operative Complications in Patients with Obstructive Sleep Apnea Eleni Giannouli, MD, FRCPC, ABIM (Sleep) Canadian Respiratory Conference, Montreal, April 28, 2017

2 Disclosures and Acknowledgements No conflicts of interest Copyright declaration This copy is provided exclusively for research purposes and private study. Any use of the copy for a purpose other than research or private study may require the authorization of the copyright owner of the work in question. Responsibility regarding questions of copyright that may arise in the use of this copy is assumed by the recipient No conflicts of interest

3 Objectives ASA guideline recommendations for the perioperative management of OSA patients Historical background of the guidelines Current challenges Review the evidence regarding increased postoperative risk in OSA patients Review the evidence supporting the main tenets of the guidelines. ASA: American Society of Anesthesiology

4 American Society of Anesthesiology (ASA) Guidelines Practice Guidelines for the Perioperative Management of Patients with Obstructive Sleep Apnea. Anesthesiology 2006; 104: Recommendations for the care of OSA patients before, during and after surgery. Endorsed by: American Academy of Sleep Medicine American Academy of Otolaryngology - Head and Neck Surgery Updated by the ASA in 2014, without significant change Practice Guidelines for the Perioperative Management of Patients with Obstructive Sleep Apnea. Anesthesiology 2014; 120:268-86)

5 American Society of Anesthesiology (ASA) guidelines Practice Guidelines for the Perioperative Management of Patient with Obstructive Sleep Apnea. Anesthesiology 2006; 104: Based on the view that OSA significantly increases the risk of Based on the view that OSA significantly increases the risk of postoperative postoperative cardiovascular and respiratory complications: cardiovascular and respiratory complications - UA collapsibility due to synergistic effects of inhaled anesthetics, iv sedation and opioids - hypoxemia and hypercarbia - sympathetic activation (SA) post-op in OSA patients - Attenuated response to vasopressors - down regulated and b- receptors - Supine position- Obesity -? REM Rebound

6 1 Aggressive preoperative screening for unrecognized OSA Patients with OSA are at risk for post-op respiratory and cardiovascular complications The Perioperative Sleep Apnea Epidemic Pre-op Diagnosis by Pre-op Screening Post-op Monitoring & Interventions (PAP Rx) 2 Initiation of perioperative CPAP therapy 3 Continuous pulse oximetry monitoring after recovery room discharge for those at increased risk of respiratory compromise. Post-op Morbidity Improve Other Health Outcomes

7 Universal preoperative screening S T O P Loud Snoring Tired (Excessive somnolence) Observed apneas High blood Pressure B BMI > 35kg/m 2 A Age > 50 years 3/8 = Suspected OSA N G Neck circumference >40cm Male Gender

8 The STOP- Bang Equivalent Model and Prediction of Severity of OSA: Relation to AHI Measured by Polysomnography. Farney et al. J Clin Sleep Med 2011 STOP-BANG Model provides a simple method for screening, estimating AHI Severity and possibly triaging patients for testing Chung, F et al. Anesthesiology 2008;108:

9 Initiation of perioperative CPAP Rationale: CPAP is a physiologic cure for hypoxemia and airway obstruction in OSA CPAP prevents cardiovascular complications in the long term Method: Lee W, Kryger MH et al. Expert Rev Respir Med 2008; Preoperative diagnosis and treatment through usual channels Speculative pre-operative de novo treatment of at risk patients Postoperative rescue therapy in symptomatic patients

10 Continuous postoperative oximetry monitoring after recovery room discharge For OSA patients assessed to be at increased risk Rationale: Lingering effects of anesthetics and analgesics on airway tone and ventilatory responsiveness Method: Chung SA et al. Anesth Analg 2008; 107: In room sitter with continuous oximetry monitoring OSA care room with one nurse monitoring oximetry for multiple OSA patient ICU, step-down unit or telemetry also acceptable

11 Who should receive postoperative oximetry monitoring? Clinically suspected OSA Diagnosed: Unwilling/ unable to use CPAP Diagnosed: Willing/ able to use CPAP Type of surgery/ anesthesia analgesia Head, neck or trunk surgery with GA Postoperative parenteral opioids Peripheral surgery with GA Worrisome symptoms? OSA severity? No Yes Moderate Severe Severe OSA severity?

12 Why were the guidelines created in spite of the paucity of evidence? Strong tradition of a patient safety culture within anesthesia Serious adverse events that are seemingly unpredictable Medical-legal threats Challenging epidemiology Relatively common disease but most patients don t even know they have it No good screening tests and confirmatory diagnostic test (PSG) is difficult to obtain.

13 What is problematic with the ASA Practice Guidelines for the Perioperative Management of Patients with OSA? The challenges of perioperative outcomes research in OSA patients Research agenda shifts to identifying unrecognized OSA and treating it instead of better understanding the nature of the risk Ethical challenges to prospective studies of OSA patients that don t follow the guidelines Inherently difficult to define and study postoperative outcomes in unrecognized OSA patients, despite representing ~80% of the prevalence.

14 Patients with OSA are at risk for post-op respiratory and cardiovascular complications? Does a Diagnosis of OSA Change Postoperative Outcomes Pre-op Diagnosis by Pre-op Screening The Perioperative Sleep Apnea Epidemic Post-op Monitoring & Interventions (PAP Rx) Do pre-op screening and post-op interventions change clinically significant postoperative outcomes? Post-op Morbidity Improve Other Health Outcomes

15 The meta-analyses % 0.7% N=5101 Kaw R, et al. Meta-analysis of the association between OSA and postoperative outcome British Journal of Anesthesia 109 (6): ,2012

16 Myocardial infarction/ischemia, arrhythmias, cardiac arrest 3.7 % 1.7 % N=2615 Kaw R, et al. Meta-analysis of the association between OSA and postoperative outcome British Journal of Anesthesia 109 (6): , 2012

17 Selection & Misclassification Bias Cohort and Meta-analyses studies: What are their limitations? Respiratory Failure had no standard definition in the different studies. Some studies were initiated as QI projects to reduce adverse post op effects (over-reporting Respiratory Failure ) Inconsistent reporting and wide range of cardiac and hemodynamic variables, not clear if reported cardiac events were new occurrences Most studies did not adjust for significant confounding factors (comorbidities, type of surgery, details about anesthesia, BMI)

18 Administrative databases Variable content and quality Administrative Database Studies: Important findings Hospital discharge abstracts and ICD codes to determine all study variables including whether or not patient had OSA OSA as pre- existing comorbidity is associated with higher ORs of : Perioperative complications (+/- cardiac complications) Pulmonary complications (re-intubation, respiratory failure) Utilization of economic resources Prolonged length of stay No difference in rates of cerebrovascular complications and mortality. Premier perspective Inc. Memtsoudis S et al. Reg Anesth Pain Med (4): Memtsoudis S et al. Anesth Analg 2014; 118: Nationwide inpatient sample. Memtsoudis S et al. Anesth Analg : Mokhlesi B et al. Chest :

19 Administrative database studies: What are their limitations? Retrospective analysis, clinical important covariates are not available. Definitions of complications problematic and overlapping Inability to correlate the post op complications with severity of OSA Relationship between ICD diagnosis of OSA and clinical OSA: unknown The increased resource utilization of services could reflect planned use of monitored settings and PAP equipment to reduce complications as per ASA guidelines Misclassification + bias in reporting complications in OSA patients Unclear if all of the reported diagnoses (e.g. PE, pneumonia, Afib) were new or older ones (a present-on-admission variable was not available for some of the studies)-? Comorbidity vs Complication

20 A Matched Cohort Study of Postoperative Outcomes in Obstructive Sleep Apnea Could Pre-operative Diagnosis and Treatment Prevent Complications? Mutter T, et al. Anesthesiology 2014;121: Linked Database of PSG data to MBH database repository ( ), at the level of individual - For each patient w DOSA and UOSA, 4 controls were matched (same surgery, indication, approximate date of surgery, n= 16,277) - Aim: Compare post op outcomes in OSA patients, before and after the diagnosis, with matched controls from general population who were at low risk of having OSA. Database of patients diagnosed with OSA by PSG Time Surgeries before diagnosis Unrecognized OSA, n = 1,571 Date of diagnosis 5 years any time Surgeries after diagnosis Diagnosed OSA, CPAP prescribed (n = 2,640) 2008

21 OSA: n=33 (0.79%) Controls: n=69 (0.42%) OSA: n=35 (0.88%) Controls: n=130 (0.84%) OSA 2.08 ( ) < Undiagnosed Diagnosed

22 Could Pre-operative Diagnosis of OSA and Treatment with CPAP Prevent Complications? the current study cannot determine whether the reduction in cardiovascular complications in DOSA was due to CPAP use or other unmeasured interventions, because data on perioperative CPAP use was unavailable

23 Patients with OSA are at risk for post-op respiratory and cardiovascular complications Does a Diagnosis of OSA Change Postoperative Outcomes Pre-op Diagnosis by Pre-op Screening? Post-op Monitoring & OSA is associated with risk for Post Op Interventions Respiratory and Cardiac Complications (PAP Rx) Severity of OSA & pre-existing dx +CPAP Rx are likely important For both Respiratory and Cardiac post-op complications, age, comorbid conditions and type of surgery are as important risk predictors, as the presence of OSA Post-op Morbidity Improve Other Health Outcomes

24 Patients with OSA are at risk for post-op respiratory and cardiovascular complications Pre-op Diagnosis by Pre-op Screening The Perioperative Sleep Apnea Epidemic Post-op Monitoring & Interventions (PAP Rx) Do pre-op screening and post-op interventions change clinically significant postoperative outcomes? Post-op Morbidity Improve Other Health Outcomes

25 Author Study Type Level of Evidence N Results Rennotte et al Gupta et al Jensen et al Case series report Postoperative CPAP Restrospective Case Control Study Home CPAP Prospective Cohort Study Home CPAP Very Low 16 No CPAP (2) vs CPAP (14) 1 st patient died, 2 nd had serious postop Cx. 14 patients CPAP Rx, no Cx Low 101 No CPAP (68) vs CPAP group (33) Serious Cx:31% vs 9% (p:0.02) Total ICU:32% vs 3% (p:0.001) Hospital Stay 7±3 vs 6±2 (p:0.03) Low 284 No CPAP/BPAP (140) vs CPAP/BPAP (144) Pneumonia: 2% vs 0.7% (NS) Hospital Stay: 2.2 vs 2.7 days (p:0.24) Liao et al Retrospective matched cohort Low 240 No CPAP (90) vs CPAP (150) Liao et al Mutter et al Randomized Controlled study Home CPAP Preoperative CPAP Retrospective Matched Cohort Study CPAP prescription Moderate 177 Postoperative Cx:46.6% vs 40.6% (p:.36) No APAP (90) vs APAP (87) Postoperative Cx:48.3% vs 48.3% (NS) Preoperative AHI vs postoperative AHI (N3) APAP: 30 to 3 (p<0.001) No APAP: 30 to 32 (p:.3) Hospital Stay: 4.3±6 vs 3.5±6 days (p:.36) Moderate 20,448 Respiratory Cx OSA + CPAP (2629) vs undiagnosed OSA (1569) OR 0.68 (95% CI, , p:.41) Cardiovascular Cx OSA + CPAP (2496) vs undiagnosed OSA (1489) OR 0.34 (95% CI, , p:0.009) Abdelsattar et al Prospective Cohort Study Moderate 2646 Untreated OSA (1465) vs treated OSA (1181) Cardiopulmonary Cx 6.7% vs 4 %, aor: 1.8 (p:.001) Unplanned re-itubations: aor : 2.5 (p:003) Myocardial infarction: aor: 2.6 (p:.03) O Gorman et al Proczko et al Unplanned ICU: 28% vs 3% (p:0.003) Effect of CPAP on Postoperative Outcomes in Surgical Patients With OSA Randomized Controlled Study Postoperative CPAP Retrospective Cohort Home CPAP Low 138 No APAP (43) vs APAP (43) Any Cx: 20.9% vs 23.3% (p:1) No significant difference between LOS Low 693 OSA + Home CPAP (99) vs STOP-Bang 3 (182) Death: 0% vs 1% (p:.5) Hospital stay 3.2 vs 4 days (p<.0001) Pneumonia: 2% vs 9.3% (p<.04)

26 Association of Adverse Postoperative Events in OSA patients with CPAP vs no-cpap treatment Association of Length of Hospital Stay in OSA patients with CPAP vs no-cpap treatment CPAP vs no-cpap: 4±4 vs 4.4±8 Nagappa etal. The Effects of Continuous Positive Airway Pressure on Postoperative Outcomes in OSA Patients Undergoing Surgery: A Systematic Review and Meta-analysis. Anesth Analg 2015;120:

27 Summary of Recommendations for Best Pre-operative Practices for Surgical patients with known OSA, Adherent or Non-Adherent to PAP, or High Probability of OSA RECOMMENDATIONS Facilities should consider having PAP equipment available for peri-operative use or have the patient bring their own PAP equipment Level of Evidence Low Grade of Recommen dation Strong Patients should continue to wear their PAP device at appropriate times during their stay in the hospital, pre and postoperatively The use of PAP therapy in previously undiagnosed but suspected OSA patients should be considered case by case. Continue use of PAP therapy in previously prescribed settings is recommended during periods of sleep while hospitalized, both pre and post-operatively. Adjustments may be needed to account for perioperative changes such as facial swelling, upper airway edema, fluid shifts, pharmacotherapy and respiratory function Moderate Low Moderate Strong Weak Strong

28 Could postoperative monitoring improve outcomes in OSA patients? No RCT of monitoring vs. no monitoring in OSA patient population No Before/ After study or other observational design in OSA patient population - Does monitoring oxygen levels with a pulse oximeter during and after surgery improve patient outcomes? Petersen T et al. Cochrane Database Syst Rev 2014; CD Continuous pulse oximetry had the potential to reduce pulmonary complications after cardiovascular surgery, however it did not reduce transfer to ICU, and did not reduce overall mortality Hypoxemia was reduced in the oximetry group, x less, in the recovery room. No statistically significant differences in : Cognitive function, Cardiovascular, Respiratory, Neurological complications were detected in the 2 groups

29 Pre-op Diagnosis by Pre-op Screening Post-op Monitoring & Interventions (PAP Rx) Post-op Morbidity Improve Other Health Outcomes - There is no clear evidence that intensive monitoring reduces post op morbidity in OSA patients 1. What is the evidence that - No conclusive data yet close Post-Op about how long, where, monitoring by whom this and other monitoring should be interventions done (PAP) change Post-Op - Unclear if post-op APAP outcomes in benefits substantially patients with moderate- severe OSA OSA? - Pre-op CPAP might 2. Is OSA severity improve postop important? outcomes in OSA

30 Patients with OSA are at risk for post-op respiratory and cardiovascular complications The Perioperative Sleep Apnea Epidemic? SCREENING Pre-op Diagnosis by Pre-op Screening 1. Should Patients be identified before Surgery? 2. When is best to screen? Post-op Monitoring & Interventions (PAP Rx) 3. Which Tools can be Used to identify patients at risk for OSA? 4. Is the strategy of pre-op screening effective in reducing postop complications? 5. What is the impact of our screening methods in this care model s cost Post-op effectiveness? Morbidity Improve Other Health Outcomes

31 Pre-op Diagnosis by Pre-op Screening SCREENING - Limited evidence of reducing postoperative complications - Cost effectiveness unsupported by data.

32 Summary of Recommendations for Screening to Identify Patients with Suspected OSA RECOMMENDATIONS Patients with a diagnosis of OSA should be considered to be at increased risk for perioperative complications Level of Evidence Moderate Grade of Recommen dation Strong Adult patients at risk for OSA should be identified before Surgery Low Weak Screening tools such as STOP- Bang, P- SAP, Berlin and ASA checklist can be used as preoperative screening tools to identify patients with suspected OSA Moderate Strong Insufficient evidence exists to support cancelling or delaying surgery to formally diagnose OSA in those identified as High Risk of OSA preoperatively, unless there is evidence of uncontrolled systemic disease or additional problems with ventilation or gas exchange Low Weak

33 Questions? THANK YOU

34 Summary of Recommendations for Best Pre-operative Practices for Surgical patients with known OSA, Adherent or Non-Adherent to PAP, or High Probability RECOMMENDATIONS of OSA Additional evaluation for preoperative cardiopulmonary optimization should be considered in patients with known or high probability OSA, who are non adherent or are not on PAP therapy, and have uncontrolled systemic conditions or additional problems with ventilation / gas exchange, such as: 1. Hypoventilation syndromes 2. Severe pulmonary hypertension 3. Resting hypoxemia in the absence of other cardiopulmonary disease Where management of comorbid conditions has been optimized, patients with diagnosed, partially treated/ untreated OSA, or suspected OSA may proceed to surgery provided strategies for mitigation of postoperative complications are implemented The risks and benefits of the decision to proceed with or delay surgery include consultation and discussion with the surgeon and the patient Level of Evidence Low Low Low Grade of Recommen dation Weak Weak Weak

35 Summary OSA is associated with increased risk for perioperative complications Age, type of operation, extend of comorbidities, severity of OSA and type of anaesthesia / analgesia are significant risk modifiers Adult patients at risk for OSA should be ideally identified before Surgery Insufficient evidence exists to support cancelling or delaying surgery to formally diagnose OSA in those identified as High Risk of OSA preoperatively, unless there is evidence of uncontrolled systemic disease or additional problems with ventilation or gas exchange

36 Summary Effective screening tools exist, but their cost effectiveness has not been proven Unclear if CPAP can prevent postoperative complications More specific data is needed to understand the best post operative monitoring practices for OSA patients Institutions should develop protocols that take into account the need for heightened awareness and locally available resources

37 Comparison of OSA Screening Tools in Surgical Patients STOP-BANG Questionnaire (n=177) Berlin Questionnaire (n=177) ASA Checklist (n= 177) P-SAP Score (n=511) Sensitivity Specificity PPV NPV LR LR DOR ROC Adapted from F. Chung et al. SASM Guidelines on Preoperative Screening and Assessment of Adult Patients with OSA. Respiration and Sleep Medicine, 2016; 123:

38 The Effects of CPAP on Postoperative Outcomes in OSA Patients Undergoing Surgery: A systematic Review and Meta-analysis. Nagappa et al. Anesth Analg 2015;120: Post op APAP reduced AHI in Post-op N3 vs standard care, but offered no significant benefit in oxygen saturation (in fact more patients on APAP needed supplemental O2), sleep parameters and other respiratory complications Compliance rate 45%. 73% due to post op pain/ discomfort, nausea and vomiting. Liao P, et al. Anesthesiology. 2013;119(4):

39 61 yo woman, BMI: 39, Hx of HTN, ESS score: 0, Neck: 38 cm, STOP- Bang: 5-6

40 19 yo man, ESS score:14, BMI:46.5, Neck: 49.5 cm, no HTN, STOP- Bang: 6 AHI: 93 supine, 77 lateral, mean SaO2: 85.3%, min SaO2: 56%, SaO2<85% (TST): 44%, AI: 87

41 43 yo man, BMI: 60, Neck: 55 cm, ESS score: 8, No HTN, STOP-Bang: 5-6 AHI: 18.3, AHI (REM): 39.2, AHI (NREM): 15.5, AI: 15 Mean SaO2: 87.5%, min SaO2: 73%, SaO2<85% : 23% TST, TcCO2: 68 mmhg (from 48 Awake)

42 We probably underuse the PACU to risk stratify patients Gali B et al. Identification of patients at risk for postoperative respiratory complications using a preoperative obstructive sleep apnea screening tool and postanesthesia care assessment. Anesthesiology 2009 Apr;110(4): Clinical risk of having OSA Recurrent PACU events Risk of respiratory and cardiovascular events Low No 2% High No 2% Low Yes 13% High Yes 37%

43 Adapted from: Seet E & Chung F. Management of Sleep Apnea in Adults- functional algorithms for the perioperative period. CJA 2010; 57:

44 Memtsoudis S, et al. The Impact of Sleep Apnea on Postoperative Utilization of Resources and Adverse Outcomes. Anesth Analg ; 118(2): Retrospective analysis of hospital discharge data in 400 US Hospitals of patients who underwent THA & TKA ( ) The presence of OSA diagnosis was based on ICD-9 codes Outcomes: Mortality, Complications, Resource Utilization were compared between the 2 groups 530,089 patients, 8.4% had OSA (32,789) OSA as pre- existing comorbidity is associated with higher ORs of : Perioperative complications (adjusted OR 1.47; CI, ) Pulmonary complications (adjusted OR 1.86; CI, ) Utilization of economic resources (adjusted OR 1.14, CI, ) Prolonged length of stay (adjusted OR 1.12, CI, ) No difference in rates of cerebrovascular complications and mortality.

45 Perioperative Auto-titrated Continuous Positive Airway Pressure Treatment in Surgical Patients with Obstructive Sleep Apnea: A Randomized Controlled Trial Anesthesiology. 2013;119(4): PSG Post- op N3 results AHI Group Pre-op N3 Post-op N3 APAP 30.1 (22-45) 3 (1-12.5) (p<0.001) Control 30.4 (23-42) 32 ( ) NS ODI Group Pre-op N3 Post-op N3 APAP (p<0.001) Control NS Min SaO2 Group Pre-op N3 Post-op N3 APAP 79% 82.5% * (p 0.03) Control 79.5% 77% NS * A significant higher % patients with APAP received supplemental O2 on post op N2, N3

46 Liao P, et al. Anesthesiology. 2013;119(4): Perioperative changes of oxygen desaturation index (ODI) (A) and cumulative time percentage with SpO 2 less than 90% (CT90) (B) from oximeter in the auto-titrated continuous positive airway pressure (APAP) and the control group. Data represented as median (middle point) and interquartile range (25th, 75th percentile) *Adjusted P < 0.05 compared with control group at the same night. Date Postop of download: = postoperative; 11/14/2015 Copyright 2015 American Society of Anesthesiologists. All rights reserved.

47 Universal preoperative screening Rationale: OSA is prevalent in the surgical population and most cases are unrecognized. A Prevalent Disorder: 27 % Women 43 % Men (ages 50-70) (General Population) 9 % 26 % (ages 30-49) 6% 13% moderate- severe OSA Surgical Patients : ~20% have OSA (as high as ~ 80% in bariatric patients) 80% of these were not previously diagnosed. (Finkel KJ et al. Sleep Med 2009; 10:753-8) Method: Clinical screening tools relied upon in the absence of a reliable screening test

48 Important Novel Results 1. The risk of CV complications (cardiac arrest and shock) was increased in severe Undiagnosed OSA (UOSA) but not in Diagnosed OSA (DOSA) 2. The risk of respiratory complications (ARDS and RF) was increased in severe OSA patients, without significant difference in risk between UOSA and DOSA 3. For both respiratory and CV post-op complications, age, comorbid conditions and type of surgery are as important risk predictors, as the presence of OSA