Morbid Obesity and Morbid Obesity and Gastric BypassGastric Bypass

Fun FactsFun Facts

61% of adults in US 61% of adults in US have BMI >25 in ’99have BMI >25 in ’99

13% of children 6-1113% of children 6-11 14% of adolescents 14% of adolescents

aged 12-19aged 12-19 How many deaths in How many deaths in

the US are associated the US are associated with obesity?with obesity?

Economic Cost? Economic Cost? National Institute of Health. National Institute of Health.

Call to Action ReportCall to Action Report

Deaths and CostDeaths and Cost

300,000 deaths per year300,000 deaths per year BMI >30 have a 50%-100% increased BMI >30 have a 50%-100% increased

risk of premature death.risk of premature death. 117 BILLION dollars in 2000117 BILLION dollars in 2000

National Institute of Health. Call to Action ReportNational Institute of Health. Call to Action Report

More Fun FactsMore Fun Facts

More non-Hispanic white More non-Hispanic white women(23%) are obese compared to women(23%) are obese compared to non-Hispanic white men(21%)non-Hispanic white men(21%)

Most affected-women are of low Most affected-women are of low socioeconomic.socioeconomic.

National Institute of Health. Call to Action ReportNational Institute of Health. Call to Action Report

Taco Bell?Taco Bell?

Mexican american Mexican american boys tend to have boys tend to have higher prevalence higher prevalence of overweight.of overweight.

National Institute of Health. Call to National Institute of Health. Call to Action Report 1998Action Report 1998

                                                                                     

Heart DiseaseHeart Disease

Hypertension twice Hypertension twice as commonas common

Increased risk: MI, Increased risk: MI, CHF, Sudden CHF, Sudden Death, Arrythmias.Death, Arrythmias.

DiabetesDiabetes

A gain of 11-18 lbs A gain of 11-18 lbs increases the risk of increases the risk of developing Type 2 developing Type 2 to twice that of to twice that of normal individualsnormal individuals

Over 80% of people Over 80% of people with DM type 2 are with DM type 2 are overweight or obeseoverweight or obese

Respiratory Respiratory

Sleep ApneaSleep Apnea Obesity Hypoventilation SyndromeObesity Hypoventilation Syndrome AsthmaAsthma Decreased FRCDecreased FRC Increased risk of aspiration from GERDIncreased risk of aspiration from GERD Difficult airways (ventilate and Difficult airways (ventilate and

intubate)intubate)

OtherOther

ArthritisArthritis Reproductive complications Reproductive complications Gallbladder disease.Gallbladder disease. Depression, Social DiscriminationDepression, Social Discrimination

What is BMI?What is BMI?

BBody ody MMass ass IIndexndex BMI=weight (kg) / BMI=weight (kg) /

height (m2)height (m2) BMI=pounds/BMI=pounds/

inches 2 x 703inches 2 x 703 Why BMI?Why BMI?

Classification Classification

Healthy Weight Healthy Weight 18.5-24.918.5-24.9

Overweight 25.0-Overweight 25.0-29.929.9

Obesity Obesity Class I 30.0-34.9Class I 30.0-34.9 Class II 35-39.9Class II 35-39.9 Class III >40Class III >40

Limitations to BMI….really?Limitations to BMI….really?

Overestimate body Overestimate body fat in persons who fat in persons who are very muscular are very muscular i.e. body buildersi.e. body builders

Underestimate Underestimate body fat in persons body fat in persons who have lost who have lost muscle mass i.e. muscle mass i.e. elderlyelderly

Surgery AspectSurgery Aspect

IndicationsIndications TypesTypes ResultsResults ComplicationsComplications

IndicationsIndications

Age 18-60Age 18-60 BMI > 40BMI > 40 BMI > 35 with BMI > 35 with

medical problemsmedical problems Exhausted other Exhausted other

venues of weight venues of weight lossloss

Types of SurgeryTypes of Surgery

How do they work?How do they work?

RestrictiveRestrictive MalabsorptionMalabsorption Behavioral modificationBehavioral modification

ResultsResults

Weight Loss- 66% at 1 Weight Loss- 66% at 1 to 2 years after to 2 years after surgerysurgery

60% at 5 years60% at 5 years 50% at 10 years50% at 10 years African-american lose African-american lose

significantly less significantly less weight…why?weight…why?

Improvement in Improvement in comorbitiescomorbities

ComplicationsComplications

Akin to any surgery i.e. infection, Akin to any surgery i.e. infection, DVT, wound deshicense, anastomotic DVT, wound deshicense, anastomotic leaks, etc.leaks, etc.

Death 1%-2% after surgery, but Death 1%-2% after surgery, but higher with other comorbities.higher with other comorbities.

Irritable bowel syndrome ….can lead Irritable bowel syndrome ….can lead to rectal problemsto rectal problems

AnesthesiaAnesthesia

Pre-OpPre-Op Intra-OpIntra-Op Post-OpPost-Op

Pre-Op/ HistoryPre-Op/ History

History and PhysicalHistory and Physical ROS ROS AirwayAirway Heart Heart LungsLungs Eyes… eyes?… yes Eyes… eyes?… yes

eyeseyes Previous anesthesiaPrevious anesthesia

AirwayAirway

Mallampati, mouth opening, tongue size, Mallampati, mouth opening, tongue size, thyromental distance, sternomental thyromental distance, sternomental distance, neck circumferencedistance, neck circumference

Predictibility of difficult intubation: neither Predictibility of difficult intubation: neither obesity or BMI predicted problems with obesity or BMI predicted problems with tracheal intubation… tracheal intubation… BUT HIGH BUT HIGH MALLAMPATI SCORE >3 and LARGE NECK MALLAMPATI SCORE >3 and LARGE NECK CIRCUMFERENCE MAY INCREASE THE CIRCUMFERENCE MAY INCREASE THE POTENTIAL FOR DIFFICULT LARYNGOSCOPY POTENTIAL FOR DIFFICULT LARYNGOSCOPY AND INTUBATIONAND INTUBATION

Anesthesia and Analgesia, Mar 2002. 732-736Anesthesia and Analgesia, Mar 2002. 732-736

CardiovascularCardiovascular

HTN: multiple HTN: multiple medications difficult medications difficult to controlto control

Cardiomyopathy, Cardiomyopathy, CHF, Ischemia, CVA, CHF, Ischemia, CVA, Pulmonary HT, DVT, Pulmonary HT, DVT, PE, PE, HypercholesterolemiHypercholesterolemia, a, HypertriglyceridimiaHypertriglyceridimia

Obesity CardiomyopathyObesity Cardiomyopathy

Patients with severe and long Patients with severe and long standing obesitystanding obesity

LVH, left ventricle dilation and LV LVH, left ventricle dilation and LV diastolic dysfunction.diastolic dysfunction.

Left Ventricle Failure and Right Left Ventricle Failure and Right Ventricle Failure = Obesity Ventricle Failure = Obesity CardiomyopathyCardiomyopathy

Causes of death are CHF and sudden Causes of death are CHF and sudden cardiac deathcardiac death

Lungs/ OSALungs/ OSA

OSA- hypersomnolence, loud snoring, OSA- hypersomnolence, loud snoring, apnea and hypopnea during sleepapnea and hypopnea during sleep Physiologic changes:Physiologic changes:

Arterial hypoxemiaArterial hypoxemia PolycythemiaPolycythemia Arterial HypercarbiaArterial Hypercarbia HTNHTN Pulmonary hypertensionPulmonary hypertension

Lungs/ OSALungs/ OSA

Risk Factors:Risk Factors: MaleMale Middle AgeMiddle Age ObesityObesity AlcoholAlcohol Drug Induced SleepDrug Induced Sleep

Lungs/OHSLungs/OHS

Obesity Hypoventilation Syndrome is Obesity Hypoventilation Syndrome is defined as:defined as: PaOPaO22 < 70 < 70 PaCOPaCO22 > 45 > 45 BMI > 30 kg/mBMI > 30 kg/m22

No other respiratory disease of No other respiratory disease of explaining the gas anomalyexplaining the gas anomaly

Lungs/OHSLungs/OHS

Why is there Why is there hypoventilation?hypoventilation?

1. High cost of work 1. High cost of work of respirationof respiration

2. Dysfunction of the 2. Dysfunction of the respiratory centerrespiratory center

3. Repeated 3. Repeated episodes of episodes of nocturnal nocturnal obstructive apneaobstructive apnea

Lungs/OHSLungs/OHS

Physiologic Changes:Physiologic Changes: Hypersomnolence (also Hypersomnolence (also

OSA)OSA) Arterial Hypoxemia Arterial Hypoxemia

(also OSA)(also OSA) Polycythemia (also Polycythemia (also

OSA)OSA) Hypercarbia (also OSA)Hypercarbia (also OSA) Respiratory acidosisRespiratory acidosis Pulmonary Pulmonary

hypertension (also OSA)hypertension (also OSA) RV Failure (also OSA)RV Failure (also OSA)

Lungs/OHSLungs/OHS

Some say that OHS progress into OSASome say that OHS progress into OSA Some say that they are different Some say that they are different

entities.entities. Who is right?Who is right? OHS are usually:OHS are usually:

Older, more obese, more deranged daytime Older, more obese, more deranged daytime ABG values, more restricted lung volume, ABG values, more restricted lung volume, more severe desaturation during sleep.more severe desaturation during sleep.

Chest, 2001:120:336-339Chest, 2001:120:336-339

Lungs/ OSA vrs OHSLungs/ OSA vrs OHS

Chicken or the Chicken or the egg?egg?

A spectrum of the A spectrum of the same disease?same disease?

EyesEyes

Hypoxia and Hypoxia and hypercarbia as a hypercarbia as a sign of angiogenesissign of angiogenesis

Case Report , Elia J. Case Report , Elia J. Duh, AMA-Assn.orgDuh, AMA-Assn.org

Intra OperativeIntra Operative

GA vrs TIVA GA vrs TIVA GA supplemented with regionalGA supplemented with regional Fast onset and fast offset medicationFast onset and fast offset medication Good muscle paralysisGood muscle paralysis Calculate drug doses according to Calculate drug doses according to

IBWIBW Best choice of maintenance is….Best choice of maintenance is….

NOT KNOWNNOT KNOWN

Post OpPost Op

ExtubationExtubation Post Op PainPost Op Pain OSA and OHSOSA and OHS CardiacCardiac

Post Op/ExtubationPost Op/Extubation

Fully awakeFully awake Recover in head up Recover in head up

positioningpositioning Monitoring very Monitoring very

important if OSA or important if OSA or OHSOHS

Post Op/ExtubationPost Op/Extubation

Maximun decrease in PaOMaximun decrease in PaO22 is 2-3 days is 2-3 days post op.post op.

Mechanical weaning can be difficult Mechanical weaning can be difficult b/c:b/c:

1. Increased work of breathing1. Increased work of breathing2. Decresed lung volumes2. Decresed lung volumes3. V/Q mismatch3. V/Q mismatch

Pain Control and OSAPain Control and OSA

Pt with OSA have a exquist sensibility Pt with OSA have a exquist sensibility to narcotics, even when used in to narcotics, even when used in regional techniques.regional techniques.

Narcotics can have depressive Narcotics can have depressive effects up to 2-3 days post opeffects up to 2-3 days post op

Post Op/ OthersPost Op/ Others

Others:Others: DVT early ambulation/ heparinDVT early ambulation/ heparin Wound infection is twice as commonWound infection is twice as common Guillain-BarreGuillain-Barre

Case Report: Chang; Obes Surg 2002 Aug; 12(4) Case Report: Chang; Obes Surg 2002 Aug; 12(4) 592-97592-97