October 2012 Volume 80 Number 5 Bernadette M. Henrichs, CRNA, PhD, CCRN Robert P. Walsh, CRNA, PhD, MBA Missouri Association of Nurse Anesthetists Missouri Association of Nurse Anesthetists Spring Meeting - Branson, MO March 23, 2013
Objectives Define obstructive sleep apnea (OSA) and sleep hypopnea (OSH). List risk factors, symptoms and treatment of OSA. Describe anesthetic implications for the patient with OSA. Review new ASA guidelines regarding management of patients with OSA.
Case Study 42 year old with obstructive sleep apnea (OSA) underwent ear surgery Awake FOI 25 mcg fentanyl x 3 during procedure Extubated when fully awake Naloxone required to facilitate awakening One hour later, patient c/o pain: 4 mg IV morphine given Cullen. J. Clin. Anes. Vol. 13(2) 2001.
Case Study Over the next two hours, patient was noted to be sleepy and unresponsive: Vital signs ordered q 30 min. Naloxone available at bedside 30 minutes later patient suffered cardiopulmonary arrest: Emergency tracheostomy performed at bedside due to difficult airway Outcome resulted in brain death Cullen. J. Clin. Anes. Vol. 13(2) 2001.
What is OSA? Greek word apnea means without breath during sleep People with untreated sleep apnea stop breathing repeatedly during their sleep Repeated episodes can last for 10 seconds or longer and can occur more than 5 times per hour, sometimes hundreds of times during the night and often for a minute or longer Leads to a fall in oxygen saturation of > 4% with the person Leads to a fall in oxygen saturation of > 4% with the person often gasping for air, making a loud, snorting breath
Obstructive Sleep Apnea (OSA) Sleep Apnea Central Obstructive ti Sleep Apnea Sleep Apnea Acute onset of irregular No airflow despite breathing unresponsive respiratory effort to chemical or vagal stimulus Airway obstruction No respiratory effort at results in loud snoring times Apneic episodes result Respiratory drive in fatigue, depression depressed during sleep
Obstructive Sleep Apnea (OSA) First description of OSA appeared in literature in 1966, however OSA described in Dickens portrayal of Joe the Fat Boy in The Posthumous Papers of the Pickwick Club, 1869: fast asleep after noon and snorting like a horse. Hark, how hard he fetches his breath Loadsman JA, et al. Anaesthesia & Sleep Apnea. BJA 2001; 86(2): 254-66.
Obstructive Sleep Apnea 1 Obstructive Sleep Apnea 2 OSA Treatment 3 Anesthesia Implications 4 ASA Guidelines
Obstructive Sleep Apnea 1 Obstructive Sleep Apnea 2 OSA Treatment 3 Anesthesia Implications 4 ASA Guidelines
1 Obstructive Sleep Apnea OSA: Statistics OSA affects 25% of men and 10% of women of middle age: Almost 20,000,000, in U.S. have OSA 1:5 have mild form of OSA 6,000,000 need treatment 500,000 000 seek treatment OSA most likely will increase as the population becomes older and more obese Pediatric population is not immune Doyle J: OSA & the surgical pt. Anesthesiology News Guide to Airway Management 2010, pp 27032; Kuna, et al. Internal Medicine website
1 Obstructive Sleep Apnea OSA: Statistics Often, a sleep-deprived bed partner is the one who convinces the snoring, apneic person to seek medical help
1 Obstructive Sleep Apnea OSA: What Is It? Pathophysiology OSA Airway A pause in breathing during sleep lasting at least 10 seconds and accompanied by at least a 4% decline in oxygen concentration Muscles that normally hold the airway open, relax during sleep. As the airway collapses, airflow is stopped or decreased. Pharyngeal collapse
1 Obstructive Sleep Apnea OSA: Pathophysiology Adapted from Benumof JL: Obesity, sleep apnea, the airway and anesthesia Curr Opin Anaesthesiol 2004; 17(1): 21-30.
1 Obstructive Sleep Apnea OSA: Symptoms Restless sleep Loud snoring Chronic fatigue due to decreased REM Poor memory and concentration Morning headache Hypertension due to O 2 yp 2 deprivation
1 Obstructive Sleep Apnea OSA: Pathophysiology Attempt to inspire against a closed glottis leads to generation of extreme negative intrathoracic pressures LV afterload Venous return Sympathetic discharge O 2 Vagal Tone O 2 (hypoxemia)
3 Anesthesia Implications Dangers of OSA OSA BP (pds of apnea) risk of MVA (7x) epi/norepinephrine; ST; HTN (SNS response) CVA risk (chronic HTN) Job impairment Pulmonary HTN RV dysfunction CHF Impaired memory, headaches, impotency Atherosclerosis; hypoxia; arrhythmias; ischemia; MI Increased platelet aggregation (inflammation)
3 Anesthesia Implications Interesting Facts 80% of people with chronic HTN have OSA: Many are not controlled with medications 50% of people with CHF have OSA 50% of morbidly obese have OSA and may also have pulmonary HTN However, many OSA pts are NOT obese Asymptomatic patients show symptoms during anesthesia!!!
1 Obstructive Sleep Apnea OSA: Risk Factors Obese male, age > 50: Obesity (BMI > 40) Large neck circumference: > 17 in males, > 16 in females GERD Smoker / ETOH Snoring Small mouth or large tongue Enlarged soft palate / uvula Enlarged tonsils / adenoids: Most common cause in children
1 Obstructive Sleep Apnea OSA: Diagnosis 10 15 episodes / hour of apnea along with one or more symptoms: Snoring Restless sleep Nightmares Excessive daytime somnolence Hypoxia stimulates awakening / gasping Tests: Polysomnography (sleep study gold standard) CT of head and neck Extensive airway examination (ENT)
1 Obstructive Sleep Apnea Diagnosis: Polysomnography
1 Obstructive Sleep Apnea Apnea Hypopnea Index Derived from the total number of apneas and hypopneas during the person s sleep time Airway resistance; snoring Obstructive Sleep Hypopnea (OSH) Decrease in airflow by > 50% for more than 10 sec. Severity: Mild: AHI = 5-15 per hour Moderate: AHI = 15-30 per hour Severe: AHI >30 per hour Obstructive Sleep Apnea (OSA) No airflow
1 Obstructive Sleep Apnea Spectrum of Obstruction Airway Resistance No significant decrease in airflow (snoring) 15 episodes of arousal/hour No significant change in oxyhemoglobin saturation Hypopnea 10 sec of 30-50% airflow reduction 15 episodes/hour May be associated with a drop of 4% in oxyhemoglobin saturation Apnea 10 sec cessation of airflow 5 episodes/hour Usually associated with a drop of 4% in oxyhemoglobin saturation COMMON TO ALL 3: Arousals with increasing ventilatory effort + daytime somnolence
Obstructive Sleep Apnea 1 Obstructive Sleep Apnea 2 OSA Treatment 3 Anesthesia Implications 4 ASA Guidelines
2 OSA Treatment Mild Sleep Apnea Lifestyle changes, including weight loss Avoid supine position during sleep Lateral position Sitting position Prone position Mandibular Assistive Devices Obtain sufficient sleep Abstain from alcohol in evening Abstain from sedatives
OSA Treatment Positioning Avoid sleeping in the supine position
OSA Treatment Positioning Non-supine/reverse Trendelenberg Three O 2 sat readings 15 min apart D/C O 2 for 3 min If O 2 <90%, restart O 2, alert medical staff, obtain blood gas (arterial or venous) Home CPAP or NIPPV restarted with O 2 for those with known OSA
OSA Treatment Abstaining Abstain from alcohol l or sedatives such as sleeping pills
2 OSA Treatment Sleep Apnea Sleep Apnea Treatment: > 20 respiratory events per hour Continuous Positive Airway Pressure (CPAP) Non-invasive Surgery Invasive
2 OSA Treatment Sleep Apnea Sleep Apnea Treatment: > 20 respiratory events per hour Continuous Positive Airway Pressure (CPAP) Non-invasive Surgery Invasive
2 OSA Treatment CPAP Noninvasive treatment t t for OSA Effective in 95% of patients Apnea, sleep apnea, OSA & Sleep disorders. http://www.cpapman.com/dieorder.htm. 5/30/05
2 OSA Treatment CPAP With Mask Complications include claustrophobia, facial skin abrasions, air leaks and conjunctivitis Victor LD: Tx of OSA. American Family Physician; 2/1/04, 1-9.
2 OSA Treatment CPAP With Mask That Connects to O 2 Flow Meter 10-25 LPM of oxygen for 1.5-10 cm H 2 O Built-in in Pressure Relief Valve Complications include claustrophobia, facial skin abrasions, air leaks and conjunctivitis i i Victor LD: Tx of OSA. American Family Physician; 2/1/04, 1-9.
2 OSA Treatment CPAP With Nasal Pillows Complications include nasal dryness and congestion and awkwardness in wearing May interfere with sexual intimacy Victor LD: Tx of OSA. American Family Physician; 2/1/04, 1-9.
2 OSA Treatment The Latest Seen in an Internet Ad in Spring 2013
2 OSA Treatment Sleep Apnea Sleep Apnea Treatment: > 20 respiratory events per hour Continuous Positive Airway Pressure (CPAP) Non-invasive Surgery Invasive
2 OSA Treatment Surgical Procedures Uvulopalatopharyngoplasty (UPPP): Removal of soft tissue in oropharynx / palate 50% successful Mandibular Maxillary Advancement Surgery: Surgical correction of facial abnormalities or throat obstruction that contribute to sleep apnea Mandibular Myotomy: Mandible is cut where tongue muscles attach, pulled outward, rotated 90, and reattached This pulls tongue forward 6-10 mm and almost always eliminates OSA
2 OSA Treatment Surgical Procedures Radiofrequency Ablation/Somnoplasty Somnoplasty: Minimally invasive procedure Uses RF energy to reduce soft tissue in pharynx Performed under L/A in an outpatient setting Laser-Assisted Uvuloplasty (LAUP): Laser surgery to remove uvula, soft tissue Tracheostomy: ): The only effective treatment before 1981 Now performed as last resort
Obstructive Sleep Apnea 1 Obstructive Sleep Apnea 2 OSA Treatment 3 Anesthesia Implications 4 ASA Guidelines
3 Anesthesia Implications Preoperative Assessment Screen patient prior to surgery to assess for risk factors: Include interview with family Determine if OSA signs / symptoms are present Consider sleep study: Untreated or inadequately treated OSA is associated with a higher incidence id of perioperative complications. Consider weight loss prior to elective surgery Assess need for preoperative initiation of CPAP with continuous use postoperatiely: Have patient bring CPAP machine to hospital so it can be used postoperatively
1 Obstructive Sleep Apnea Diagnosing OSA It is estimated that as many as 90% of persons with obstructive sleep apnea are undiagnosed.
1 Obstructive Sleep Apnea Screening for OSA: Berlin Questionnaire Screening tool developed during Conference on Sleep in Primary Care in 1996 in Berlin, Germany Self-administered questionnaire consisting of 11 questions Used home portable sleep monitor to validate rather than polysomnography (which is the gold standard) When Berlin questionnaire was combined with a 14-item checklist recommended by ASA, moderately high level of sensitivity resulted in accurately diagnosing OSA Helpful in detecting patients at high risk for OSA but not easy to use because of complex scoring system
1 Obstructive Sleep Apnea Screening for OSA: STOP BANG Questionnaire Self-administered screening tool consisting of 4 yes/no questions addressing Snoring, i Tiredness, d Observed d apnea and high blood Pressure (STOP) Practical; easy to use When combined with BMI,, Age, g, Neck size and Gender (STOP-BANG), sensitivity and positive predictive value for detecting OSA increased significantly, especially moderate to severe OSA Concise and conclusive; validated in surgical patients
1 Obstructive Sleep Apnea Screen for OSA: STOP BANG Questionnaire
3 Anesthesia Implications Preoperative Considerations Anesthesia plan: Regional block vs LA vs. GETA? Post-operative pain management strategy: NSAIDS vs. opioids PCA (basal rate vs. bolus setting) What medication?
3 Anesthesia Implications What is the best anesthetic?..... No simple answer OSA patients are at risk for respiratory compromise with sedatives and opioids For superficial procedures, consider LA or peripheral blocks with little or no sedation Monitor capnography during procedure Consider GETA over moderate/deep sedation Consider spinal or epidural for lower extremity Consider spinal or epidural for lower extremity procedures
3 Anesthesia Implications If GETA Chosen... Anticipate difficult ventilation & difficult airway: Most likely will need oral/nasal airway; 2-hande mask ventilation Emergency airway cart / consider awake FOI Fully reverse muscle relaxants Extubate and recover in a lateral, semi-upright position Consider using airway exchange catheter so rapid re-intubation can be performed
3 Anesthesia Implications GETA Virtually all anesthetic drugs diminish pharyngeal muscle tone: Propofol, thiopental, opioids, benzodiazepines, N 2 O, volatile agents The deeper the anesthetic, the more collapsible the pharynx Use agents with low Consider avoiding N 2 O in the obese: Potential for pulmonary HTN Decreases ability to maximize oxygenation
Solubility ( Speed ) The lower the solubility of agent: The quicker the agent diffuses into brain tissue with induction The quicker the agent diffuses from brain tissue back into the lungs with emergence The lower the solubility of agent, The quicker the wake-up The less risk for hypoxic episodes in the PACU The less risk for aspiration
Fat/Blood Partition Coefficient (Solubility) Desflurane 27.2 Isoflurane 44.9 Sevoflurane 47.5 The higher the number, the slower the agent is cleared from the body when it is turned off.
3 Anesthesia Implications Consider Dexmedetomidine Alpha 2 agonist IV infusion that can be started preop for awake intubation, and continued intraop and postop through h extubation ti Causes sedation, hypnosis, anxiolysis Inhibits sympathetic activity; decreases B/P and HR Analgesic; Decreases narcotic need No respiratory depression Prevents shivering i
1 Obstructive Sleep Apnea Postoperative Complications Hypoxemia; oxygen desaturation; prolonged need for supplemental oxygen Pneumonia; atelectasis, respiratory failure Tachycardia, bradycardia, hypotension, HTN Arrhythmias. atrial fibrillation Myocardial ischemia Confusion, agitation; postoperative delirium Excessive drowsiness Longer length of stay; increased ICU admission; readmission to the hospital within next 30 days
3 Anesthesia Implications Postoperative Management OSA patients are high risk for obstruction and hypoxemia Vigilantly monitor patient in PACU and step-down floor or ICU Respiratory status should be closely monitored by checking respirations and by pulse oximetry Oxygen will help with hypoxemia but may increase incidence of apneic periods Drummond GB. Controlling the airway. Anesthesiology 2002; 97(4): 771-773.
3 Anesthesia Implications ASA Guidelines: Caveat Supplemental oxygen may increase the duration of apneic episodes & may hinder detection via pulse oximetry of atelectasis, transient apnea & hypoventilation. www. osahq.org
3 Anesthesia Implications Postoperative Management CNS suppression owing to anesthesia, sedation and analgesia/pain meds may exacerbate sleepdisordered breathing and further asphyxia- related complications. REM sleep is decreased the night after surgery followed by REM rebound. Breathing gproblems during REM sleep can triple on postoperative day 2 & 3. Vasu TS et al. OSA & postoperative complications. Archives of Otolaryngology-Head & Neck Surgery 2010;
3 Anesthesia Implications Postoperative Management For postop pain, consider regional anesthesia with LA, NSAIDS, dexmedetomidine Give lowest effective dose of analgesic & sedation Keep antagonists close (nalaxone, flumazenil) Use CPAP mask in PACU and floor Monitor for a median of 3 hours longer than non-osa pts before e discharge from an outpatient facility Monitor for a median of 7 hours after the last episode of airway obstruction or hypoxemia while patient is breathing room air in a quiet, unstimulated t environment Gross JB, Bachenberg KL, Benumof FL et al: ASA Practice guidelines for pts with OSA. Anesthesiology 2006; 104(5): 1081-93.
3 Anesthesia Implications Postoperative Management ASA Closed Claims Project database identified 19 claims involving sleep apnea patients: 18 of 19 sustained death or brain damage related to adverse respiratory system events None of the patients were wearing CPAP None of the patients were wearing CPAP during postoperative phase
3 Anesthesia Implications Postoperative Management CPAP is probably bl underused d in the PACU where the potential for upper airway obstruction is high, and in the postoperative period where obstruction is an increased risk because of the use of narcotic analgesics or sedative drugs Hillman DR, Platt PR, Eastwood PR. The upper airway during anaesthesia. British Journal of Anaesthesia, 2003; 91(1): 31-39.
3 p y s Anesthesia Implication Post-op op Day 3 Exacerbation of respiratory compromise may occur on postoperative day 3 or 4 The OSA patient is at risk for REM rebound as sleep patterns are re-established estab s ed
Anesthesia Implications To Discharge or Not To Discharge Well-treated OSA pts having low risk procedures performed under L/A or regional anesthesia with little or no sedation and minimal need for narcoticbased analgesics can be discharged after surgery. A majority of anesthesiologists surveyed would discharge OSA pts after L/A or regional anesthesia unless postop narcotics were required. Bryson GL. Patient selection in ambulatory anesthesia. Can J of Anest 2004; 51:768-81.
Anesthesia Implications The Real Questions... Do we really know the incidence of OSA among our patients? Can those who have OSA be identified prior to Can those who have OSA be identified prior to surgery so that the patient can be treated prior to surgery and the anesthetic care can be modified to meet the needs of the OSA patient?
Obstructive Sleep Apnea 1 Obstructive Sleep Apnea 2 OSA Treatment 3 Anesthesia Implication 4 s ASA Guidelines
4 ASA Guidelines ASA Guidelines for OSA Guidelines developed by ASA in 10/2005 on how to care for OSA patients and updated in 2006 Panel of 12 physicians (anesthesiologists, bariatric surgeon, otolaryngologists and two methodologists) Reviewed published evidence, interviewed anesthesiologists, obtained opinions from a panel of consultant
4 ASA Guidelines ASA Guidelines: Recommendations Preoperative e evaluation ation be performed in advance of day of surgery: Allow for preparation of perioperative management plan Preoperative use of CPAP Fully awake extubation of patients with OSA: Verification of full reversal e from NMBD Semi-upright position for extubation / recovery
4 ASA Guidelines ASA Guidelines: Recommendations Respiratory CO 2 monitoring should be used during moderate or deep sedation GETA is preferable to deep sedation for superficial procedures GETA is preferable to moderate or deep sedation for OSA patients undergoing procedures involving the upper airway: Upper endoscopy Bronchoscopy
4 ASA Guidelines ASA Guidelines: Recommendations Spinal / epidural anesthesia should be considered for peripheral procedures Regional analgesic techniques should be considered to reduce or eliminate the requirement for systemic opioids Supplemental O 2 should be administered continuously until patient is able to maintain baseline S a O 2 on room air.
4 ASA Guidelines ASA Guidelines: Recommendations Continuous pulse oximetry monitoring after discharge from PACU is recommended If frequent or severe airway obstruction or hypoxemia occurs during postoperative monitoring, i initiation iti of nasal CPAP or NIPPV should be considered Each facility should develop its own guidelines, based on the ASA guidelines, for management of patients with OSA
Example of a Case Study from our Institution Healthy farmer Orthopedic surgery Respiratory arrest on the floor postoperatively Subsequent questioning with family members revealed typical signs and symptoms of OSA How often does this happen?
Our Concern with OSA Not all hospitals screen for OSA As many as 90% are undiagnosed Increased risk for post-operative respiratory complications
Possible Solutions 1. Identify patients risk levels 2. Flag patients 3. Offer diagnostic test for OSA 4. Identify risk of surgery for OSA complications 5. Alert Respiratory Therapy, Sleep Medicine & Surgical Placement Coordinator 6. Educate patient, families, staff, faculty 7. Change practice
Identify Risk levels Use the STOP-BANG Questionnaire on all patients admitted to the hospital or coming in for surgery NO RISK LOW RISK MODERATE RISK HIGH RISK
ASA PERIOPERATIVE OSA RISK SCORING SYSTEM A Severity of OSA (from sleep study or pre-existing diagnosis) Points: (0-3) None (Apnea hypopnea index less than 5) 0 Mild (Apnea hypopnea index 6-20) 1 Moderate (Apnea hypopnea index 21-40) 2 Severe (Apnea hypopnea index greater than 40) 3 A Risk for OSA (from OSA screening if no pre-existing diagnosis) No Risk 0 Low Risk 1 Moderate Risk 2 High Risk 3 B Invasiveness of surgery and anesthesia Points: (0-3) Superficial surgery under local or peripheral nerve block Anesthesia without sedation Superficial surgery with moderate sedation or general anesthesia Peripheral surgery with spinal or epidural anesthesia (with no more than moderate sedation) Peripheral surgery with general anesthesia Airway surgery with moderate sedation Major surgery, general anesthesia Airway surgery, general anesthesia C Requirement for postoperative opioids Points (0-3) None 0 Low dose oral opioids 1 High dose oral opioids, parenteral or neuraxial opioids 3 Overall Score = A + the greater of B or C. 4 increased perioperative risk from OSA 5 significantly increased perioperative risk from OSA 0 1 2 3 Points: (0-6) Flag Patient Patient at Risk OSA wrist bands Warning sheets in charts A Stamp on H&P OSA Risk in the comment section of OR schedule PATIENT AT RISK FOR OBSTRUCTIVE SLEEP APNEA (OSA) {Based on Definitive Diagnosis or Screening Questionnaire} ***See guidelines on reverse side*** Page sleep medicine at 253-1902 for a consult or with questions regarding treatment. For CPAP / BIPAP call respiratory therapy (Pager: 848-8116). 8116) American Society of Anesthesiology OSA Risk Score:
Other Measures Offer sleep study to diagnose those who have obstructive sleep apnea Identify risks associated with OSA in surgical patient Respiratory complications Avoid or limit narcotics Use CPAP postoperatively Monitor closely in PACU and on floor
Summary: Sleeping & Breathing Breathing and sleeping are two very basic processes. If you stop breathing for more than a few minutes, life itself stops. Sleep is a little more forgiving, but if you stop sleeping, or fail to achieve a truly rejuvenating sleep, it is not long before life is pretty miserable. Drazen N Engl J Med 2002; 346:390
Thank you!
References American College of Physicians: Health care topics: Sleep apnea. 3/15/06 http://www.doctorsforadults.com/topics/dfa_slee.htm Dept of Otolaryngology/Head gy and Neck Surgery: Obstructive sleep apnea. 3/14/06. Http://www.entcolumbaa.org/osa.htm Eastwood PR, Szollosi L, Plat PR, Hillman DR. Collapsibility of the upper airway during anesthesia with isoflurane. Anesthesiology 2002; 97: 786-793. Fogel RB, Malhotra A, SHea SA, Edwards JK, White DP. Reduced genioglossal activity with upper airway anesthesia in awake patients with OSA. J Appl Physiol. 2000; 88: 1346-1354. ASA Practice Guidelines for the Perioperative Management of Patients with ASA Practice Guidelines for the Perioperative Management of Patients with Obstructive Sleep Apnea. ASA website. 3/16/06.
References Ho Am, Chung DC, To EW, Karmakar MK. Total airway obstruction ti during L/A in a non-sedated patient with a compromised airway. Canadian J of Anesthesia 2004; 52: 838-841. Isono S, Tanaka A, Takashi N. Lateral position decreases collapsibility of the passive pharynx in pts with OSA. Anesthesiology 2002; 97(4): 780-785. Jaffe RA, Samuels SI. Anesthesiologist s Manual of Surgical Procedures. Third Edition. Lippincott Williams and Wilkins. Philadelphia. 2004. Kuna ST. A 54-year-old man with OSA. JAMA 2002; 288(6): 1-15. Piccirillo JF: OSA. JAMA, 2000; 284: 1492-94. 94
References Sleep apnea information and resources. http://www.stanford.edu/~dement/apnea.html. dement/apnea.html. Downloaded on 3/16/06. Stalford CB. The starling resistor: A model for explaining and treating OSA. AANAJ 2004; 72(2): 133-140. Vi t LD T t t f OSA i i A i F il Victor LD: Treatment of OSA in primary care. American Family Physician: Feb 1, 2004, 1-9