OSA Obstructive Sleep Apnea

1. OSAObstructive Sleep Apnea With Case Scenarios

2. Definition • OSA Assessment – ARHCC (draft) Feb 1st, 2012 DRAFT ONLY • This guideline is based on broad principles and is not intended to substitute for the clinical judgment of Anaesthesiologists where individual patient-specific factors may require alteration of these recommendations (Seet & Chung 2010). • Focus • Obstructive Sleep Apnea (OSA) is clinically defined by the occurrence of daytime sleepiness, loud snoring, witnessed breathing interruptions, or awakenings due to gasping or choking in the presence of at least 5 repetitive partial or complete upper airway obstruction events lasting ten or more seconds per hour of sleep (Epstein et al, 2009). • The recurring airway obstruction causes repeated arousals and increased sympathetic output that culminates in daytime hypersomnolence and memory loss. It is the most prevalent of sleep disorders, seen in about one in four males, and one in ten females (Seet & Chung, 2010). • OSA is associated with a number of co-morbidities including hypertension, heart failure, myocardial infarction, diabetes mellitus, gastroesophageal reflux disease and cerebrovascular events (Perioperative Management of OSA Patients: Practical Solutions and Care Strategies, OSA Symposium, 2010).

3. Adult patients with OSA are at increased risk of difficult intubations and postoperative respiratory distress/ obstruction, and therefore are at increased risk for perioperative morbidity and mortality secondary to their increased sensitivity to sedation, anaesthesia and analgesia in proportion to the severity of their OSA. • Patients on OSA therapy should be instructed to bring their therapy machine or dental appliance with them on the day of surgery

4. OSA basics physiology • OSA occurs due to repetitive occlusion of the pharyngeal airway during sleep. OSA patients have structurally a more narrow and collapsible pharyngeal airway than non-OSA persons. • The pharynx is a multipurpose organ. Under supervision of neural and chemical controls, contraction of the pharyngeal muscles surrounding the pharyngeal airway modulates its size and stiffness according to purpose. For instance, the pharyngeal airway constricts to efficiently propel food into the esophagus during swallowing. • Maintenance of a rigid and patent pharyngeal airway is mandatory for achieving adequate respiration.

5. Chung, Eikermann, Gay • Both anaesthesia and postoperative analgesic measures can negatively affect OSA outcomes. The effects of anaesthesia, sedation, and analgesics may work similarly, increasing the risk of detrimental effects to patients with OSA. • During wakefulness, upper airway dilator muscle activity is high in patients with OSA .These protective reflexes are diminished during the transition from wakefulness to sleep, leading to collapse of the pharyngeal airway in anatomically predisposed individuals. Evidence suggests that the consequences of sleep and anaesthesia-induced unconsciousness are related.

6. Known OSA patients previously on PAP (Positive Airway Pressure) therapy should be en­couraged to be compliant with PAP therapy postoperatively. Also, it may be prudent to monitor patients with OSA with oximetry or telemetry monitoring. • Regarding ambulatory surgery, short-acting aesthetic agents and non-invasive surgery typically makes this a safer option for patients with OSA. However, severe untreated or undiagnosed OSA requiring postoperative narcotics after ambulatory surgery may be unsafe.

7. Night time can be a particularly vulnerable time for patients with OSA, as sleep and sedation from critical respiratory depression appear very similar. In order to ensure patient safety, close monitoring when narcotics are required may be necessary throughout the night. Moreover, by monitoring patients with known OSA for a longer time period postoperatively, adverse outcomes such as postoperative airway problems, respiratory failure, ischemia, delirium, and death may be avoided. • How long do we monitor an OSA patient post op after receiving a narcotic? Opoid data

8. Case 1 • Male 63 years old. • Spouse attends to loud disturbing snoring at night • Is known to stop breathing for short periods of time while sleeping • Has not been diagnosed with sleep apnea • Frequently tired during the day • Weight 230 lbs. Height 5’10” • Neck girth 17” • Hypertensive 145/93. Taking antihypertensive medication. • No history of illness recently. Coming in for scheduled screening colonoscopy due to family history of Bowel CA.

9. What are this patient’s risk factors for OSA • Age • Gender • Hypertension • Weight – neck girth • Snoring • Chronically tired even after sleep • Stops breathing for short periods of time while sleeping

10. Stop Bang Questionnaire(given for all surgical patients in SDC)We are hoping this would be filled out by the surgeon’s office prior to booking the patient for Endoscopy. Section A Screening for Sleep Apnea: • Have you been diagnosed with sleep apnea? (stop breathing while you are asleep?) • Do you use a CPAP, bi-level machine or dental device to help you breathe while sleeping?

11. Section B • Do you snore loudly (louder than talking or loud enough to be heard through closed doors)? • Do you often feel tired, fatigued, or sleepy during daytime? • Has anyone observed you stop breathing during your sleep? • Do you have or are you being treated for high blood pressure?

12. Section C • BMI: more than 35 kg/m ? – (patient significantly overweight.) • Age: over 50 years old? • Neck circumference: Male: > 43 cm (17 in.) Female: > 40 cm (15 in.)? • Gender: male? YES to 3 or 4 Items Request Aesthetic Chart Review Diagnosed OSA or YES to > 5 Items Request Aesthetic Consult

13. Sedation for OSA patient Propofol is the recommended sedation for an OSA patient and would be administered by an anaesthetist. • Would you expect a narcotic be given with the Propofol for pain? Why or why not? • What safety devices are in place in GDC to protect this patient should they not be protecting their own airway?

14. Case scenarios • Case 1 • You receive this patient back from the procedure room, known OSA patient, and their B/P is low 80/53, an oral airway is in. How often do we do repeat B/P? Rationale? Answer

15. Case 2 • A patient coming in for a procedure requiring procedural sedation. Patient states they do not have a ride home afterwards, only a taxi. Patient is 60 years old, overweight and lives alone. B/P is 143/95 on admitting. Patient states he does snore at night and often wakes himself up. • Q 1 • Is it prudent to do this patient and have him stay an extra 2 hours after receiving Versed and Fentanyl to recover in GDC? • Q 2 • What are your concerns specifically knowing what you have gathered from admitting him? • Q3 • How could you most safely do this patient in GDC? answers

16. STOP BANG QUESTIONAIRE

17. Questions to consider when admitting • Above 50 years of age • Male • Neck size above 17” for male, 15” for female.. • Loud snoring? • Stop breathing at night • Tired after sleeping all night • History of Hypertension. • These are indicators that put patients at risk for sleep apnea. If patients have 3 or more of the above predictors they are at a higher risk after sedation with a narcotic. We should be notifying physicians that these patients are at risk. Risks are greatly reduced if given Propofol without a narcotic. • Considerations: • Does patient take narcotics at home for chronic pain? • Encourage patient to use their CPAP machine at home during the day when resting, not just at night. • Should not be scheduled last in the day as patient may require a lengthened recovery time.

18. Questions to consider before discharge of an OSA patient • Patients are not suitable for discharge if any of the following events have occurred in the last 30 minutes. • Oxygen desaturation of less than 90 % (3 episodes) • Bradypneas – less than 8 breaths per minute. (3 episodes) • Apnea greater than 10 seconds (1 episode) • Not taking narcotics for pain • *(events observed in a quiet environment)

19. In-patient • When giving report to the ward notify patient OSA and risks involved. • Consider holding patient longer in recovery • Suggest pt be on Oxymetry post-op.

20. Algorithm Guideline for Management of Obstructive Sleep Apnea in Adults for the Preoperative Period

22. When the term "short acting anesthetic" is used as a safer option for the OSA patient, is Versed  considered short acting as well as Propofol or is it just not the use of a narcotic with the sedative? • Propofol is the primary "short acting anesthetic".  It is ananesthetic Induction agent.  When it is (incorrectly) used for "Conscious Sedation" it is still a General Anesthetic that is being induced, it is definately not a "Conscious Sedation" in any way.  When I'm in the scope room, the patients are getting a true (short) general anesthetic. • Midazolam is a Hypnotic Sedative.  It is for "Conscious Sedation" (hopefully Conscious), not for inducing General Anesthesia.  Midaz is MUCH longer acting than propofol, and dangerous when mixed with narcotics for Conscious sedation.  Not a good option for OSA patients.  Midaz will potentiate the respiratory depression of the narcotic. • Curt Smecher

23. Your Questions?

24. References: • http://osa.arhcc.bc.ca/node/3 • http://osa.arhcc.bc.ca/sites/default/files/files/user3/NUXX104927B_ObstructiveSleepApneAdultScreening.pdf • http://osa.arhcc.bc.ca/sites/default/files/files/user3/2012%20Feb%201%20OSA%20.pdf • http://online.lexi.com/crlsql/servlet/crlonline

25. Answer • BP and pulse are required 5 minutes after giving Fentanyl/Versed in the procedure room. If the patient remains heavily sedated and hypotensive, you would continue to do q 5 minute vitals no matter where they are. A further question may be to ask if they should be back in the recovery area with an oral airway still in. Return to powerpoint

26. Answers • 1. The recovery in GDC is not necessarily the crucial time period. Patient may continue at risk for many hours and there is no one at home to monitor him throughout the day and night. • 2. Patient has numerous risk factors for OSA even though he has not been diagnosed. Age, weight, gender, snoring and hypertension. • 3. The safest way this patient could be sedated in GDC would be with the use of Propofol. A prudent nurse would point the risk factors out to the physician and scoping team. Return to PowerPoint

27. Opoid Comparison Morphine IV: Onset 5 – 10 minutes Peak 20 minutes Duration 4 hours Fentanyl IV: Onset immediate Peak 3 – 5 minutes Duration .5 to 1 hour Synergistic effects when combined with Benzodiazepines (Versed) effects respiratory depression. Last viewed slide

28. Cycle of OSA O2 Pharynx closes Activates SNS Sleep deepens Arousal SNS activity Open Pharynx O2

29. Heightened levels of CO2 in blood and lungs becomes a Cerebral Vascular problem. Decrease in CV activity. Increased CO2 effects mental status • Fluid shift in the lungs. • Worst day is 3 nights post-op. • AHI remains high for 7 days post-op • ETCO2 is gold standard. O2 sat not effective till too late. • Let ward know they are a potential OSA patient if discharged to the ward.