Operative risk in patients with Operative risk in patients with Obstructive Sleep Apnea Syndrome Obstructive Sleep Apnea Syndrome

(OSAS).(OSAS).

Why give preference to Why give preference to RA?RA?

Luc SermeusLuc Sermeus

Antwerp University HospitalAntwerp University Hospital

BelgiumBelgium

ESRA winterweek 2012ESRA winterweek 2012

OSA: OSA: characteristicscharacteristics

• SnoringSnoring

• Apnea caused by airway obstructionApnea caused by airway obstruction

• ArousalArousal

AnesthesiaAnesthesia

== a state of a state of unrousableunrousable

unconsciousnessunconsciousness

OSA: Preop OSA: Preop assessmentassessment

• OSA already diagnosedOSA already diagnosed

• OSA not (yet) diagnosed (80-95%)OSA not (yet) diagnosed (80-95%)

• 82% men, 93% women 82% men, 93% women

• Polysomnography / nocturnal oxymetry / Polysomnography / nocturnal oxymetry / HolterHolter

• Cancel surgery? Cancel surgery?

C.L. Wang et al. Sleep Breath 2011, 16 (ahead of C.L. Wang et al. Sleep Breath 2011, 16 (ahead of print)print)

““Half of Chinese anesthesiologists lacked sufficient Half of Chinese anesthesiologists lacked sufficient knowledge and had low confidence levels in dealing knowledge and had low confidence levels in dealing

with OSA patients”with OSA patients”

OSAKA- questionaryOSAKA- questionary

Preop OSA: Preop OSA: symptomssymptoms• SnoringSnoring

• Men 44% > women 28%Men 44% > women 28%

• 30-60y, peak 50-60y30-60y, peak 50-60y

• Obesity (60-90%) BMI > 30kg/m²Obesity (60-90%) BMI > 30kg/m²

• BMI: Western > Asian , prevalence OSA BMI: Western > Asian , prevalence OSA similar similar

5% in men, 2% in women 5% in men, 2% in women (Young, J Resp Crit Care Med 2002)(Young, J Resp Crit Care Med 2002)

Preop OSA: Preop OSA: symptomssymptoms

• SnoringSnoring

• PredispositionPredisposition

• Alcohol, Upper airway infectionAlcohol, Upper airway infection

• Hypertrophic tonsils, nasal obstructionHypertrophic tonsils, nasal obstruction

• Craniofacial anatomy (Kushida Craniofacial anatomy (Kushida Laryngoscopy 2000)Laryngoscopy 2000)

• Lower facial height, more backward Lower facial height, more backward position jaw in Asian populationposition jaw in Asian population

Airway obstruction with apneaAirway obstruction with apnea

• Obesity Obesity

Correlation: fatty tissue lateral of pharynx & OSACorrelation: fatty tissue lateral of pharynx & OSA

Neck Ø > 42-44 cm Neck Ø > 42-44 cm fast collapse of airwayfast collapse of airway

• Micro- / retrognathiaMicro- / retrognathia

• Hypertrophic tonsils, big tongue, position of hyod Hypertrophic tonsils, big tongue, position of hyod bonebone

• Maxillar hypoplasia, narrow oropharynx, shape of Maxillar hypoplasia, narrow oropharynx, shape of airway airway

(Ishiguro, Oral Surg Med Path Radiol Endosc 2009) (Ishiguro, Oral Surg Med Path Radiol Endosc 2009)

Preop OSA: Preop OSA: symptomssymptoms

CHEST August 2005 vol. 128 no. 2 896-901Igor Fajdiga, MD, PhD

CHEST August 2005 vol. 128 no. 2 896-901Igor Fajdiga, MD, PhD

Normal Apneic

American Journal of Respiratory and Critical Care Medicine Vol 168. pp. 522-530, (2003)Richard J. Schwab et al.

BMI = 32BMI = 32

Preop OSA: Preop OSA: symptomssymptomsArousalArousal

• OO22↓↓, CO, CO22↑↑, ventilatory effort, ventilatory effort↑↑, stretch-, stretch-receptorsreceptors↑↑

“ “awake”awake”

• Not totally conscious - muscle toneNot totally conscious - muscle tone↑↑- - obstructionobstruction↓↓

• Massive sympathetic activationMassive sympathetic activation

bradycardia bradycardia tachycardiatachycardia

AHT AHT

Cardiac ischemia - CVACardiac ischemia - CVA

OSA: pathophysiologyOSA: pathophysiology

Pharyngeal collapsein OSA

Sympathetic Drive

Intrathoracic Pressure

Myocardial OxygenSupply

VasoconstrictionPeriph. ResistanceHeart rateOxygen demand

Venous returnAfterloadPreload

* LVH

* RV dilatation

*Stroke Volume*LVEF*TD velocities of LV and RV

BP

Stru

ctural

alterations

Fu

nction

alalteration

sCardiovascular changesCardiovascular changes

OSA: consequencesOSA: consequences

•AHT: related to severity OSA (risk 10XAHT: related to severity OSA (risk 10X↑↑))

•Arrhythmia's: nocturnal in 50%, risk2-4XArrhythmia's: nocturnal in 50%, risk2-4X↑↑ if if hypoxemiahypoxemia↑↑

• Mostly NSVT Mostly NSVT

• Sinus arrest, second degree AV-block, VES, AFSinus arrest, second degree AV-block, VES, AF

•Cardiac ischemia:Cardiac ischemia: 14-28%14-28% = 5x normal= 5x normal

•Heart-failure: 11-37%Heart-failure: 11-37%

•Pulmonary HT 20-42% Pulmonary HT 20-42% Right heart-failure Right heart-failure

OSA: OSA: consequencesconsequences• Hypoxemia Hypoxemia polycythemia polycythemia

• Stroke: 62-77% of stroke has OSAStroke: 62-77% of stroke has OSA

• SeveritySeverity↑↑ of OSA = Riskof OSA = Risk↑↑ of stroke of stroke

• Terminal renal insuff: 40-60% = f(duration) of Terminal renal insuff: 40-60% = f(duration) of OSAOSA

• DiabetesDiabetes

• Edema UAEdema UA

• Impaired chemosensitivityImpaired chemosensitivity

OSA: OSA: consequencesconsequences

Cardio vascular risk Cardio vascular risk ↑↑ with severity and duration with severity and duration OSAOSA

Overall risk of CVD = x11Overall risk of CVD = x11

= 15-20% fatal complication if severe OSA = 15-20% fatal complication if severe OSA >10j>10j

Risk post therapy = mild OSA = 4-5% Risk post therapy = mild OSA = 4-5%

Control = Control = ±±2%2%

Marin et al. Lancet Marin et al. Lancet 20052005

Preop OSA: Preop OSA: premedicationpremedication• Benzodiazepines: CAVEBenzodiazepines: CAVE

Muscle toneMuscle tone↓↓ collapse collapse apnea apnea SatSat↓↓

Pulsoxymetry / CPAP Pulsoxymetry / CPAP

• Anti-sialorrhea: GlycopyrrolateAnti-sialorrhea: Glycopyrrolate

• CPAP : to be started, if possible, 2w before CPAP : to be started, if possible, 2w before surgerysurgery

OSA + Consequences + Co-OSA + Consequences + Co-pathologypathology

= perop / postop risk= perop / postop risk

Perop OSA: anestheticsPerop OSA: anesthetics

ALL ANESTHETICS :ALL ANESTHETICS :

•Negative effect on cardiac functionNegative effect on cardiac function

•CollapsibilityCollapsibility↑↑

•Arousal responseArousal response↓↓↓↓ if O if O22↓↓, CO, CO22↑↑, obstruction, obstruction

•Ventilatory responseVentilatory response↓↓ if O if O22↓↓, CO, CO22↑↑

•UA reflexesUA reflexes↓↓

Physiology: FRCPhysiology: FRC

FRC = OFRC = O22-reserve if apnea-reserve if apnea

• BMIBMI↑↑ = FRC = FRC↓↓ + O + O22-consumption-consumption↑↑

• Supine position = FRCSupine position = FRC↓↓

• Anesthesia/sedation = FRCAnesthesia/sedation = FRC↓↓

preoxygenation before induction of preoxygenation before induction of anesthesiaanesthesia

= filling FRC with ±100% O= filling FRC with ±100% O22

Perop OSA: UAPerop OSA: UA

21,9% difficult UA if OSA 21,9% difficult UA if OSA ↔↔ normal normal 2,6%2,6%

➡5% failed intubation (=100x 5% failed intubation (=100x normal) normal)

66% with a difficult intubation had OSA66% with a difficult intubation had OSA

Savva D.1994 Br J Anaesthesia 73(2):149-53Savva D.1994 Br J Anaesthesia 73(2):149-53

Chung F et al. 2008 Anesth Analg 107(3):915-20Chung F et al. 2008 Anesth Analg 107(3):915-20

Perop OSA: UAPerop OSA: UA

• Difficult Upper AirwayDifficult Upper Airway

• Experienced anesthetistExperienced anesthetist

Inadequate face mask ventilationInadequate face mask ventilation

Difficult ( > 2 attempts) intubationDifficult ( > 2 attempts) intubation

• Predictive factorsPredictive factors

• ComplicationsComplications

• Dental injury / UA traumaDental injury / UA trauma

• Severe hypoxia Severe hypoxia cerebral ischemiacerebral ischemia

+ laryngoscopy + laryngoscopy asystoleasystole

OSA: prediction OSA: prediction difficult UAdifficult UA

• Anatomical factorsAnatomical factors

• Craniofacial morphology / trauma / surgeryCraniofacial morphology / trauma / surgery

• Cervical mobility / mouth openingCervical mobility / mouth opening

• Micro- / retrognathia / macroglossiaMicro- / retrognathia / macroglossia

• Long soft palateLong soft palate

• MallampatiMallampati

MallampatiMallampati

Mallampati 3-4 + OSA = difficult intubation Mallampati 3-4 + OSA = difficult intubation until proven otherwiseuntil proven otherwise

Cormack - LehaneCormack - Lehane

Difficult intubationDifficult intubation

==

Difficult Difficult extubation!!!extubation!!!

OSA: Difficult OSA: Difficult extubationextubation CausesCauses

• AnatomyAnatomy

• Residual sedationResidual sedation

• Instrumentation UAW during intubation / surgery Instrumentation UAW during intubation / surgery of UAof UA

• EdemaEdema

• BloodBlood

• SecretionsSecretions

• Nasal packsNasal packs

OSA: difficult OSA: difficult extubationextubation

•5% life threatening postextubation 5% life threatening postextubation obstruction following surgical treatment of obstruction following surgical treatment of OSAOSA

OSA: difficult OSA: difficult extubationextubation

Pre requisitesPre requisites

• Complete recovery of muscle relaxationComplete recovery of muscle relaxation

• Wide awake / communicatingWide awake / communicating

• Spontaneous breathing Spontaneous breathing adequate TV adequate TV

oxygenationoxygenation

• Semi sitting position Semi sitting position FRCFRC↑↑

OSA: difficult OSA: difficult extubationextubation

Pre requisitesPre requisites

•Stable haemodynamicsStable haemodynamics

•CPAPCPAP +/- O2

•Re-intubation equipment readyRe-intubation equipment ready

•Perop corticosteroids if necessaryPerop corticosteroids if necessary

•Intensive care / Medium care if necessaryIntensive care / Medium care if necessary

OSA: postop OSA: postop complicationscomplications

• Rebound REM ±3Rebound REM ±3thth day postop. day postop.

• PainPain↓↓, surgical stress, surgical stress↓↓ ±normal sleep pattern ±normal sleep pattern

• Obstruction, apnea, sympathetic activationObstruction, apnea, sympathetic activation

• Hemodynamic instability (pt not yet Hemodynamic instability (pt not yet recovered)recovered)

• Confused / CVAConfused / CVA

• Disturbed wound healingDisturbed wound healing

• Myocardial ischemia / infarction / sudden Myocardial ischemia / infarction / sudden deathdeath

• NB: respiratory depression lasts for a week NB: respiratory depression lasts for a week (morphine??)(morphine??)

OSA: conclusionsOSA: conclusions

• OSA = cause of cardio-vascular complicationsOSA = cause of cardio-vascular complications

• OSA = cause of difficult UA OSA = cause of difficult UA

• Enough reasons to prefer RA and to convince Enough reasons to prefer RA and to convince your patientyour patient

Obstructive Sleep Apnea, Stroke, and Cardiovascular DiseasesBagai, Kanika MD, MSThe Neurologist

Issue: Volume 16(6), November 2010, p 329–339

LiteratureLiterature