Dr Alireza Yarahmadi and Dr Arvind Perathur Mercy Medical Center - Winter Retreat Des Moines February 2012

Transcription

1 Dr Alireza Yarahmadi and Dr Arvind Perathur Mercy Medical Center - Winter Retreat Des Moines February 2012

2 Why screen of OSA prior to surgery? What factors increase the risk? When due to anticipate problems? How do you expedite work up of OSA given time constraints? (Dr Yarahmadi) What to do in the post operative period?

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4 Retrospectively review N =101 patients with OSA - hip or knee replacement surgery Time of OSA diagnosis - before (n = 36) or after (n = 65) Control =101 without OSA who underwent the same operations. Complications 39% of patients with OSA 18% of control patients(p =.001). Serious complications ie ICU transfer for cardiac ischemia or respiratory failure 24% of patients with OSA versus only 9% of controls (P =.004) Hospital stays were longer for patients with OSA compared with controls (P <.007). Most complications occurred during the first day after surgery, but a small number occurred as late as postoperative days 4 and 5. Gupta RM, Parvizi J, Hanssen AD, Gay PC. Postoperative complications in patients with obstructive sleep apnea syndrome undergoing hip or knee replacement: a case control study. Mayo Clin Proc 2001; 76:

5 Acute respiratory failure Mental status changes Delirium and CO2 narcosis Poor control of HTN Atrial fibrillation Stroke and MI

6 Snoring AHI > 5 AHI > 10 AHI > 15 Age (Yrs) (%) (%) (%) (%) < > AHI = Apnea Hypopnea Index Unfortunately or fortunately older folks undergo surgeries more frequently

7 Propofol, Thiopental, Opioids, Benzodiazepines, NMBs, Inhalational Anesthestics cause pharyngeal collapse Respiratory center depression Decrease tone of pharyngeal muscles Decrease cough in the situation of an already compromised airway

8 Sleep architecture is disturbed first 3 days Different medications can result in decrease REM eg benzos Days 3-5, patients experience REM sleep rebound Sleep apnea is worse in REM (loss of muscle tone) Apnea risk increased for 1 week post-op REM rebound may contribute to poor hemodynamic outcomes from profound sympathetic activation

9 Peri operative complications increase with severity of OSA Anesthestic drugs used, duration of procedure and specific surgical ie thoracic, ENT or upper airway related, neurosurgery Difficult airway due to anatomy May play significant role in unexplained MIs, stroke or death (AHI > 15 are at risk)

10 Make diagnosis and grade severity (Dr Yarahmadi) Plan for airway management Plan for pain management Plan for post-op monitoring

11 Inpatient vs. Outpatient Regional vs. General Post-op non invasive ventilation

12 OSA independent factor for difficult intubation may be as high as 5% Limited jaw protrusion, abnormal neck anatomy, obesity, moderate to severe OSA consider awake intubation (without paralytics) Good topicalization, limit sedatives

13 Retrognathia Dr Lawler Blog Google Images

14 Dr Lawler Blog Google Images

15 Regional or local anesthetic technique NSAID Clonidine PCA - IV narcotic, no basal infusion

16 High risk, 5% post-extubation obstruction Fully reversed, fully awake Semi-upright position Oral or nasal airway Consider extubating directly to Non invasive ventilation ie CPAP or BiPAP

17 O 2 SAT and neurological status evaluation (CO2 narcosis) Patient should be on his PAP machine if he has one Outpatients may be discharged if they meet discharge criteria but careful with opiates

18 Objectives: Sensitivity? Specificity of screening tools? -Sleep Study Vs. -Apnea-link Vs. -STOP BANG Vs. -Overnight Pulse Ox American sleep association (ASA)& American Society of Anesthesiologists (ASA) recommendations.

19 Types of Monitoring Devices Type1: In-lab PSG. Type 2: At home PSG. Type 3: ( Apnea-link) Measures minimum of 4 variables. Airflow, RR, HR, O2, snoring,... Limitation: can not distinguish wakefulness from sleep. Type 4: Measures minimum of 1 channel, like pulse ox.

20 Apnea-link

21 Apnea Link Validation* AHI Sensitivity % Specifity % > > > > *Journal of Clinical Sleep Medicine, Vol. 3, No. 4, 2007

22 STOP S (Snore) Have you been told that you snore? YES/NO T (Tired) Are you often tired during the day? YES/NO O (Obstruction) Do you know if you stop breathing or has anyone witnessed you stop breathing while you are asleep? YES/NO P (Pressure) Do you have high blood pressure or are you on medication to control HTN, CHF, or A fib? YES/NO

23 BANG B (BMI) Is your body mass index greater than 35? YES/NO A (Age) Are you 50 years old or YES/NO N (Neck) Do you have a neck circumference greater YES/NO than 40 cm? G (Gender) Are you a male? YES/NO HIGH RISK of OSA: answering YES to 3 or more items (patient should have a formal sleep study) LOW RISK of OSA: answering YES to less than 3 items

24 Predictive Parameters for STOP BANG* Mild Sleep Apnea AHI > 5 Sensitivity % 83 Specifity % 56 Moderate Sleep Apnea AHI > Severe Sleep Apnea * Anesthesiology, V 108, No. 5, May 2008

25 What is the role of overnight pulse oximetry? Some studies have evaluated overnight pulse oximetry, using percentage of desat or the total time spent at less than 90% saturation. This approach is probably adequate for screening for suspected severe OSA, but not all patients.

26 American Society of Anesthesiologists Task Force Recommendations: Perioperative evaluation should include: An interview related to snoring, apneic episodes, frequent arousals, morning HA, and daytime somnolence. Physical exam to evaluate the airway, neck circumference, tonsil size. Sleep Study, Specific sleep studies were not indicated.

27 American Sleep Association 2006 guidelines OSA is a major risk factor for perioperative adverse events. Surgical pts should be screened to determine their OSA risk. Postoperative pain management in patients with OSA should minimize the use of opioids or other sedatives. Such patients should receive postoperative CPAP therapy as soon as possible. Patients also should undergo close pulse oximetry monitoring in a step-down setting after surgery.

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