Obesity, OSA and bariatric surgery
Transcript of Obesity, OSA and bariatric surgery
8/7/2019 Obesity, OSA and bariatric surgery
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Obesity, OSA and bariatric surgery
Teoh Sc
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Case 1 of 20
` 31 year old cook
` Morbidly obes BMI 45
` Lap gastric banding
` HPT/DM/hyperlipidemia
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Case 1 of 20
` Multidiscipline management
` Surgical, anaes, dietician, endocrinologist
` Premedication round ? OSA
` -snorring
` -HPT
` -?apnea
` -BMI
` -neck circumference 47cm` -male
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Case 1 of 20
` ?delays surgery
` Benefit and risk
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obesity
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Obesity
` BMI=Weight(kg) / height2 (m)
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Definition
WHO classification BMI cut off fordefinition
Asian BMI cut off for action
Underweight <18.5 <18.5
Normal 18.5-24.9 18.5-22.9
Overweight 25-29.9 23-27.4
Obese class I 30-34.9 27.5-32.4
Obese class II 35-39.9 32.5-37.4
Obese class III
(Morbid Obesity
40 37.5
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Types
`
Primary or secondary` Central android
` waist/hip ratio > 0.9 in female & > 0.8 in male
`
Peripheral gynaecoid` Buttocks & thighs
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Pharmacokinetics` Vd
` o blood volume
` o CO
` q lean body mass
` Protein binding normal` oVd for lipophilic drugs
` NormalVd for hydrophilic drugs
` oGFR & renal clearance
` No change in liver clearance
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Perioperative concern
` Airway difficulty
` H/o OSA
` 1o or 2o
` End organ damage
` Drug interaction eg amphetamine
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Difficult airway
` Desaturation- increase O2 demand, reduce FRC
` Difficult mask ventilation, difficult intubation
` Aspiration
` RSI with CP or awake fibreoptic
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Predictors of difficult mask ventilation
` Overweight (BMI > 26)
` Beard
` Elderly (Age > 55 )
` Snoring
` Edentulous
` 5% incidence
` 2 factors predictiveO. Langeron et al Anesthesiology 2000;92:1229-36
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Difficult intubation
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OSA
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ASA task force. Anesthesiolo 2006 104: 1081-93
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STOP
` Validate OSA screening for surgical patients
` Concise, easy to use
`
Moderate high sensitivity & NPV
` > sensitive to moderate & severe OSA
Chung F et al. Anesthesiology 2008; 108: 812-21
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STOP
` Snoring
` Tiredness
` O bserved apnea
` High BP` 2 yes : high risk for OSA
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STOP
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STOP
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STOP BANG
` BMI > 35
` Age > 50
` Neck circumference > 40
` Gender - male
` High risk if yes 3
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STOP BANG
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Polysomnography
` Monitor ECG, EEG, EMG, oximetry
` Oronasal airflow with thermistor or pressure
transducer
` Respiratory effort via inductance or impedancepneumography and/or diaphragmatic EMG
` Body position
` LSAT
` Lowest SaO2 a/w abnormal respiratory event
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Anaesthetic considerations
` Aspiration` Polycythemia
` Pulmonary hypertension
Pashayan AG et al. Anesthesiology Clin N Am 2005; 23: 431-43
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Difficult intubation
` o difficult intubation in OSA(16.7% vs 3.3%)
` AHI higher in difficult intubation
(67.4 vs 49.9)
K im JA et al. Can J Anesth 2006; 53: 393-7
27.6% 19.3%
3.3%
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Preop recommendations
` Pre procedure identification Of OSA status improves
outcome
` Preop CPAP
` Preop NIPPV, mandibular advancement, oral appliances
` Preop weight loss
OSA task force, Anesthesiology 2006; 104: 1081-93
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Benefits of CPAP
` qAHI
` Improves O2 saturation
` q excessive daytime sleepiness
` q systemic hypertension
` Improves right heart failure
` Improves neurocognitive function.
Roop K et al. Chest 2006; 129: 198-205
Ryan F et al Am Rev Respir Dis 1991; 144: 939-44
Jain SS et al. Curr O pin Pulm Med 2004; 10: 482-8
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Intraops
` Avoid sedative premed` Regional
` GA
` -RSI
` -awake fibreoptic intubation
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Chung F et al. Anesth Analg 2008; 107: 915-20
Post op complications
` 27% vs 9%
` Respiratory most common
` 83% due to desaturation
` Incidence of post op complication
among patients with difficult airway
21%
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Periop risk
`
Severity of OSA
` Invasiveness of procedure
` Requirements of postop analgesia
` PACU observation
ASA task force. Anesthesiology 2006; 104: 1081-93
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postops
` adverse respiratory event` OSA, apnea, altered respiratory drive
` Rapid desaturation, difficult airway
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monitoring
` -GICU` -anaes male oncall room
` -anaes female oncall room
` -anaes specialist oncall room
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postops
` O2 supplement, CPAP` Opioid sparring, multimodal analgesia
` Pulmonary rehab
` DVT prophylaxis
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Bariatric Surgery
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Medical therapy
Combination of phentermine and fenfluramine (Phen-Fen) ² associated with valvular heart disease and pulmonaryhypertension; no longer approved by FDA
Sibutramine inhibits the reuptake of noradrenaline, serotonin,
and dopamine increase satiety after the onset of eating
Orlistat blocks digestion and absorption of dietary fat by bindinglipases in the GI tract
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Types of surgery
Adjustable gastric banding.
A, Proximal pouch. B, Adjustable
band. C, Needle access port
through which saline is injected
or removed to vary the size of the
adjustable band.
Roux-en-Y gastric bypass.
A, A 15- to 30-mL gastric pouch with
connected jejunal limb. B, Site of
jejuno-jejunostomy
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Anaesthesia` Considerations for obesity and its associated problems, in particular
` Airway considerations ² airway options
` Reflux / regurgitation ² acid aspiration prophylaxis
` Anaesthetic technique
` GA with endotracheal intubation ² RSI or awake FOB
` Usual considerations for laparoscopic surgery ² effects of pneumoperitoneum
on respiratory mechanics & CVS
` Postoperative management
` Consider HDU/ICU management especially if significant co-morbidities or h/o
OSA
` Postoperative pain management
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Complications
RYGB anastomotic leak
gastric pouch outletobstruction
jejunostomy obstruction gastrointestinal (GI)
bleeding
wound infection
dumping syndrome protein-calorie
malnutrition
More common after openRYGB
AGB band erosion
erosive oesophagitis
herniation of the stomach
upward inside of the band band migration
disconnections at theportal site between thetube and reservoir
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summary
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Perioperative concern for obese pt
` Airway difficulty
` H/o OSA
` 1o or 2o
` End organ damage
` Drug interaction eg amphetamine
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Obesity
` n=6336
` Multivariate regression analyses
` Obesity was not a risk factor for development of postop complications
Dindo D et al. Lancet 2003; 361:2032-5
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STOP BANG or ASA
` Screening:` Obes, difficult airway
` All patients
` Risk and benefit of proceed
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Periop risk
`
Severity of OSA` Invasiveness of procedure
` Requirements of postop analgesia
` PACU observation
ASA task force. Anesthesiology 2006; 104: 1081-93
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Anaesthesia` Considerations for obesity and its associated problems, in particular
` Airway considerations ² airway options
` Reflux / regurgitation ² acid aspiration prophylaxis
` Anaesthetic technique
` GA with endotracheal intubation ² RSI or awake FOB
` Usual considerations for laparoscopic surgery ² effects of pneumoperitoneum
on respiratory mechanics & CVS
` Postoperative management
` Consider HDU/ICU management especially if significant co-morbidities or h/o
OSA
` Postoperative pain management
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references
` Sharmeen Lotia and Mark C. Bellamy, Anaesthesia and morbidobesity Contin Educ Anaesth Crit Care Pain (2008) 8(5): 151-156
` Gerges FJ. Anesthesia for laparoscopy: a review. J Clin Anesth
2006; 18: 67-78
`
ASA task force Anesthesiology 2006; 104: 1081-93` Chung F et al. Anesthesiology 2008; 108:812-21