Transcript Perioperative Management of Patients with OSA

Perioperative Management
of Patients with Obstructive
Sleep Apnea (OSA)
Dr. Bertrand Lau
Department of Anaesthesia
Burnaby Hospital
Disclosures

No financial relationships or commercial
interests relevant to the content of this talk
OSA Overview
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Definition:
≥ 5 apneas/hypopneas per hr
 Apnea hypopnea index (AHI):
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5 – 20
 Moderate: 21 – 40
 Severe: >40
 Mild:
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Prevalence
4% of men, 2% of women
 24% of those older than 65
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Why does OSA happen?
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Because humans talk!
Sleep Disordered Breathing in OSA
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Arousal events
Verifiable on EEG
 Activates the pharyngeal muscles &
 The sympathetic nervous system (SNS)
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↓O2
Activate SNS
Pharynx Closes
Sleep Deepens
Arousal
SNS activity↓
Opens Pharynx
↑O2
Pathophysiology of OSA
Systemic & pulmonary hypertension
 CVA
 LVH → ischemia → arrhythmias → death
 RVH → cor pulmonale
 Negative pressure pulmonary edema
 GERD
 Social problems: Day time sleepiness,
nocturnal social isolation
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Perioperative Respiratory Problems
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Anaesthetic:
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Impaired respiratory mechanics due to GA
Worsened loss of pharyngeal muscle tone
Decreased respiratory drive due to anaesthetic and
analgesic agents
Surgery:
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Impaired respiratory mechanics from positioning
Splinting from pain
Direct airway trauma leading to edema
Other Perioperative Problems
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Surgical stress response, pain, fluid shifts,
respiratory complications etc., also lead to:
M.I.
 CVA
 CHF
 Arrhythmias
 Post-op delirium
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Rate of Complications in TJA
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Gupta, Parvizi et al. 2001 Mayo Clin Proc
Restrospective, case-control study
 Total joint arthroplasties
 N=202
 OSA vs. no OSA
 Post-op complication rates: 39% vs. 18%
 Serious complication rates: 24% vs. 9%
 LOS: 6.8 vs. 5.1 days
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Rate of Complications in
Elective Surgery
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Chung et al., 2008 Anesthesiology
Complication rate: 27.4% vs. 12.3%
 Most common problem: SpO2 ≤ 90%
 Especially on 3rd night post-op
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Respiratory Disasters
Failure to secure the airway at induction
 Airway obstruction soon after extubation
 Respiratory arrest after the administration
of opioids and/or sedation
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Case Presentation
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55 y.o. male for laparoscopic nephrectomy with:
 Obesity, BMI 42
 Hypertension
 Type 2 diabetes
 Stable coronary artery disease
 Heart
attack 3 years ago, treated with PTCA
GERD
 Possible Difficult Airway
 Known untreated OSA by O/N oximetry
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Case Continued
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Intra-operative
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T 9/10 Thoracic epidural placed
Awake fiberoptic intubation
Larger than expected incision
Extubated in OR uneventfully
PACU
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Required 50 mcg Fentanyl iv in PACU
Reasonable pain control with thoracic epidural using
hydromorphone & bupivacaine infusion
Required 6 L/min O2 by mask for SpO2 of 96%
No desaturations or obstructions noted in PACU
records
Case Continued
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Surgical Ward
Thoracic epidural at 7mL/h
 Patient reports increasing pain at 2130h
 Surgeon’s sc morphine orders followed
 10 mg sc morphine administered
 No concerns noted on assessment at 2200h
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Case Continued
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0010h Pt found to be:
Obtunded
 RR 22, Room air SpO2 76%
 Nurse gives 0.4 mg naloxone (Narcan)
 Patient is responsive to voice
 Anaesthetist on-call paged, arrives & applies
nasal airway, mask O2
 Eventually reintubates and admits to ICU
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Case Continued
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ABG’s:
Time
pH
pO2
pCO2
HCO3 Remarks
0030h 7.15 72
91
31
Initial
0220h 7.19 67
84
31
Mask O2
0505h 7.24 70
75
29
Ventilated
1654h 7.41 89
next d
43
27
Nasal prongs
Case Continued
Patient found to have had NSTEMI
 Treated for laryngeal edema & extubated
next day
 Echocardiogram showed good function
 Patient declined further investigations as
preop MIBI scan normal
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Swiss Cheese Model of Incident
Occurrence
Critical
incident
What can we do about it?
Pre surgical screening & risk stratification
 Pre surgical optimization
 Intraop anaesthetic & surgical techniques
 PAR monitoring/screening
 Proper patient disposition to an area with
appropriate monitoring
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Preop screening & risk stratification
for OSA
STOPBANG Questionnaire
 History & physical
 O/N Polysomnography (PSG)
 O/N Oximetry
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STOP BANG questionnaire
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Snoring
Tired
Observed apneas
High Blood Pressure
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BMI > 35
Age >50
Neck Circ > 40 cm
Gender - male
STOPBANG stats in the obese
Sense Spec
PPV
NPV
AHI >
15
96%
38%
54%
93%
AHI
>30
100%
29%
28%
100%
37%
51%
98%
Need 99%
for
CPAP
SIM2PLE2 History
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Sleepiness (Epworth Score)
Impotence
Menopause
Morning:
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Headache
Confusion
Dry mouth or sore throat
Personality change
Learning impairment
Exudate (Night sweats)
EtOH or sedative use
Physical
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Hard tissue craniofacial abnormalities
Retrognathia
 Micrognathia
 Brachycephaly
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Soft-tissue enlargement:
Uvula
 Tonsils
 Tongue
 Soft palate
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Risk Stratification
History and Physical can rule out OSA
 To risk stratify:
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Overnight polysomnography (PSG)
 Overnight oximetry
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O/N Polysomnography
EEG
 EOG, EMG
 EKG
 Airflow
 Respiratory effort indicators
 SpO2
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Overnight Oximetry
Poor man’s PSG
 Cannot rule out OSA
 Tends to underestimate severity in those
with moderate to severe OSA
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Presurgical Optimization
Weight Loss
 Cardiovascular disease risk modification
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Blood pressure control
 CHF management
 Diabetes management
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OSA therapy:
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CPAP, BiPAP, dental appliances
Anaesthetic & Surgical Techniques
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Anaesthetic:
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Good:
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Regional Anaesthesia
Local Anaesthesia
NSAIDs
Tylenol
Bad:
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GA
Deep sedation
Long acting narcotics
Neuraxial narcotics
Basal PCA rates
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Surgical
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Good:
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Superficial
Head up positioning
Bad:
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Major cavitary
Airway surgery
Trendelenberg
Avoiding Airway Obstruction
Post Extubation
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Obtain Information:
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Safe Extubation:
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OSA risk
Method and ease of intubation
Awake
Upright
Verified full reversal of NMB
Extubate on 100% O2
Preparation for reintubation
Immediate reinstitution of CPAP
PAR Care
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Same principles listed apply:
Use CPAP if available
 Avoid sedatives
 Minimize narcotic use
 Consider NSAIDs, Tylenol
 Ask for local anaesthetic based techniques
 Close monitoring & screening
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PAR Monitoring/Screening
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ASA OSA Guidelines:
“Patients with OSA should be monitored for a
median of three hours longer than their OSA
counterparts before discharge from the facility.”
“Monitoring patients with OSA should continue
for a median of seven hours after the last
episode of airway obstruction or hypoxemia
while breathing room air in an unstimulating
environment.”
Proposed FHA PAR Pathway
Min. 1 hr with continuous pulse oximetry
 Upon meeting PAR discharge criteria:
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Surgical daycare & home
 Ward without OSA monitoring
 Ward bed with OSA monitoring
 ICU or SCCU with OSA cardio-respiratory
monitoring
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Surgical Daycare & Home
Drug requirements minimal
 Apneas / Airway obstructions: none
 SpO2 never < 88%
 Therapy compliant preoperatively (CPAP)
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Ward without OSA Monitoring
Drug requirements minimal
 Apneas / Airway obstructions: none
 SpO2 never < 88%
 Therapy compliant preoperatively (CPAP)
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Mild or Moderate OSA
Ward with OSA monitoring
Drug requirements not minimal
 Apneas / Airway obstructions: noted
 SpO2 < 88%
 Therapy:
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compliant preoperatively (CPAP); or
 Non-compliant but only mild or moderate OSA
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ICU or SCCU with cardiorespiratory monitoring
Drug requirements not minimal
 Apneas / Airway obstructions: noted
 SpO2 < 88%
 Therapy non-compliant preoperatively and
severe OSA
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A Changing & Challenging Field
Relative lack of appreciation of OSA
 Lack of PSG availability
 Risk stratification still under development
 Stretched post-op care resources &
production pressure
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Key points
OSA is common & it is bad perioperatively
 We won’t identify all of those who have it &
we are even worse at classifying severity
 Need to be vigilant:
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Extubate properly
 Monitor for apneas, obstructions, desats
 Watch narcotic & sedative use
 Consider alternate post-op disposition & pain
management techniques
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