1. POSTOPERATIVE COMPLICATIONS OF OBSTRUCTIVE SLEEP APNEA Jason Shiffermiller, MD, MPH

2. Outline  Effects of surgery on patients with obstructive sleep apnea  More frequent apneas  Longer-lasting apneas  Results of increased postoperative apneas  Respiratory  Cardiac  other

3. Supine Positioning

4. REM Rebound

5. Opioids and Sedatives  More frequent apneas  Increased sleep time  Reduced upper airway tone  Longer-lasting apneas  Termination of apneic events requires partial arousal from sleep  Opioids and sedatives blunt this arousal response

6. Complications  15% of patients with Obstructive Sleep Apnea developed postoperative complications compared to 3% of controls  Type of complications  Respiratory Hypoxia and/or hypercapnia Atalectasis Wheezing  Cardiac Myocardial ischemia/infarction Hypotension Tachycardia  Other GI and procedure site bleeding Pulmonary embolus

8. Respiratory  Case series of patients with Obstructive Sleep Apnea published in 1997  Case 1: 41 y/o female, total hip arthroplasty, died after developing respiratory arrest on POD#3  Case 2: 66 y/o male, bilateral knee arthroplasty, found unresponsive and could not be resuscitated on POD#3  Case 3: 47 y/o female, hernia repair, found to be cyanotic on POD#2, initially resuscitated but later died  Retrospective review of patients with moderate to severe Obstructive Sleep Apnea published in 2002  3 of 19 developed postoperative respiratory arrest

9. Cardiac  Case report demonstrates hemodynamic changes associated with apneic episodes  Pulse increase of up to40 bpm coinciding with hypoxia  Similar increases in SBP with levels above 180 mmHg coinciding with arousal  Hemodynamic instability did not respond to supplemental oxygen but resolved with CPAP  Postoperative nocturnal hypoxia precipitated myocardial ischemia in patients undergoing major vascular surgery

10. Other  Delirium  Lower mean nocturnal oxygen saturation on the first two postoperative nights correlates with lower mental status during the third postoperative day  P < 0.005  Unplanned transfer to the ICU  33.3% in patients with undiagnosed Obstructive Sleep Apnea  12.3% in patients with known Obstructive Sleep Apnea  6% in controls  p = 0.003  Length of Stay  7.2 days in patients with Obstructive Sleep Apnea not using CPAP  6.0 days if patients on CPAP  5.1 days for patients in the control group  p = 0.007

11. References  Jain et al. Curr Opin Pulm Med 2004;10:482-8.  Meoli et al. Sleep 2003;26:1060-5.  Kaw et al. Chest 2006;129:198-205.  Hwang et al. Chest 2008;133:1128-34.  Ostermeier et al. Anesth Analg 1997;85:452-60.  Parikh et al. J Arthroplasty 2002;17:635-42.  Reeder et al. Anaesthesia 1991;46:849-53.  Reeder et al. Br J Anaesth 1991;67:626-31.  Rosenberg et al. Surgery 1993;114:76-81.  Gupta et al. Mayo Clin Proc 2001;76:897-905