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Perioperative Management of Perioperative Management of the Morbidly Obese Patient the Morbidly Obese Patient

Errol P Lobo MD PhDErrol P Lobo MD PhDProfessor of Anesthesia and Professor of Anesthesia and

Perioperative CarePerioperative CareUniversity of California San University of California San

FranciscoFrancisco

The Challenge The Challenge –– Postoperative pain management of Postoperative pain management of the morbid obese patientthe morbid obese patient

The number of patients who The number of patients who present for elective surgery, present for elective surgery, with a BMI of greater than with a BMI of greater than 30 kgm30 kgm--22 has increased has increased significantly.significantly.Patients who are morbidly Patients who are morbidly obese, also present with obese, also present with multiple comultiple co--morbid morbid conditions including conditions including pulmonary and cardiac pulmonary and cardiac diseasedisease

Pulmonary Mechanics in Morbid Pulmonary Mechanics in Morbid ObesityObesity

�� Decrease of total pulmonary compliance (up to Decrease of total pulmonary compliance (up to 70%)70%)

�� Reduced chest wall compliance (tissue accumulation around ribs, Reduced chest wall compliance (tissue accumulation around ribs, diaphragm, intraabdominal)diaphragm, intraabdominal)

�� Reduced lung compliance (increased pulmonary blood volume, Reduced lung compliance (increased pulmonary blood volume, ⇓⇓⇓⇓⇓⇓⇓⇓ FRCFRC))

�� Increase of total pulmonary resistanceIncrease of total pulmonary resistance�� Mainly due to increased lung resistance (airway res istance)Mainly due to increased lung resistance (airway res istance)

�� Respiratory muscle insufficiency and increase Respiratory muscle insufficiency and increase work of breathingwork of breathing

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Respiratory Physiology in the Respiratory Physiology in the Morbid Obese Obese PatientPatient

Effect on Lung VolumesEffect on Lung Volumes�� FRC decreased; declines with increasing BMI (positionalFRC decreased; declines with increasing BMI (positional))

�� ERV and TLC decreasedERV and TLC decreased

�� RV normal or increasedRV normal or increased

�� Minute ventilation increasedMinute ventilation increased

Sugerman HJ. Pulmonary function in morbid obesity. Gastroenterol Clin North Am. 1987 Jun;16(2):225Sugerman HJ. Pulmonary function in morbid obesity. Gastroenterol Clin North Am. 1987 Jun;16(2):225--37.37.

Respiratory Physiology in the Morbid Obese Patient

Pulmonary Gas ExchangePulmonary Gas Exchange

�� Oxygen consumption increasedOxygen consumption increased

�� Carbon dioxide production increasedCarbon dioxide production increased

�� Increased AIncreased A--aDOaDO22 and shunt fractionand shunt fraction

�� Oxygen consumption increases sharply with exerciseOxygen consumption increases sharply with exercise

Sugerman HJ. Pulmonary function in morbid obesity. Gastroenterol Clin North Am. 1987 Sugerman HJ. Pulmonary function in morbid obesity. Gastroenterol Clin North Am. 1987 Jun;16(2):225Jun;16(2):225--37.37.

PREPRE--OPERATIVE EVALUATION OF RESPIRATORY OPERATIVE EVALUATION OF RESPIRATORY FUNCTIONFUNCTION

A full set of PFTs will demonstrate the presence of A full set of PFTs will demonstrate the presence of obstructive and/or restrictive lung disease. Use of obstructive and/or restrictive lung disease. Use of bronchodilators will help obstructive lung disease. bronchodilators will help obstructive lung disease. Restrictive lung disease evaluation will determine how Restrictive lung disease evaluation will determine how the patient will fare in the postthe patient will fare in the post--operative period. operative period.

Generally, PFTs are not indicated.Generally, PFTs are not indicated.

ABG may be more usefulABG may be more useful

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Morbid Obesity and the Cardiovascular SystemMorbid Obesity and the Cardiovascular System

�� Blood VolumeBlood VolumeTotal blood volume is increased and as a result Total blood volume is increased and as a result increased resting increased resting

cardiac outputcardiac output

�� HypertensionHypertensionHigh incidence of hypertension in obese patientsHigh incidence of hypertension in obese patients

�� Ischemic Heart DiseaseIschemic Heart DiseaseObesity is independent risk factor for ischemic heart disease. The Obesity is independent risk factor for ischemic heart disease. The

high incidence of hypertension, diabetes, hypercholesteremia high incidence of hypertension, diabetes, hypercholesteremia compound the problemcompound the problem

Cardiac FunctionCardiac Function

Increased cardiac outputIncreased cardiac output

LVEDP increased with LVH (eccentric)LVEDP increased with LVH (eccentric)

Ventricular systolic function impairedVentricular systolic function impaired

CardiomyopathyCardiomyopathy

PREPRE--OPERATIVE CARDIAC EVALUTION OF THE OPERATIVE CARDIAC EVALUTION OF THE

MORBIDLY OBESE PATIENTMORBIDLY OBESE PATIENT

Usual preoperative evaluation should include an EKG Usual preoperative evaluation should include an EKG and a CXRand a CXRIf cardiac history yields symptoms and limited exercise If cardiac history yields symptoms and limited exercise tolerance, or if patients are in the New York Heart tolerance, or if patients are in the New York Heart Association Class III or IV category, then at the very Association Class III or IV category, then at the very least a transleast a trans--thoracic echocardiogram is indicated.thoracic echocardiogram is indicated.For stressful surgery where there may be significant For stressful surgery where there may be significant blood loss or fluid shifts, a dolbutamine echocardiogram blood loss or fluid shifts, a dolbutamine echocardiogram may be helpful.may be helpful.

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Obstructive Sleep ApneaObstructive Sleep Apnea

Defined as 10 seconds or more of total Defined as 10 seconds or more of total cessation of airflow despite respiratory effortscessation of airflow despite respiratory effortsClinically relevant are 5 episodes/hour or >30 Clinically relevant are 5 episodes/hour or >30 episodes/nightepisodes/nightPersistent effort without airflowPersistent effort without airflowFloppy upper airwayFloppy upper airwayProfound muscle relaxation during sleep or Profound muscle relaxation during sleep or anesthesia worsens syndromeanesthesia worsens syndromeThere is a significant association between There is a significant association between morbid obesity and sleep apneamorbid obesity and sleep apnea..

Diagnostic Criteria for OSA.Diagnostic Criteria for OSA.

Obstruction of airflow in OSA can be incomplete Obstruction of airflow in OSA can be incomplete (hypopnea) or total (apnea). (hypopnea) or total (apnea).

The diagnostic criterion for OSA is based on the The diagnostic criterion for OSA is based on the Apnea/Hypopnea index (AHI). The AHI is derived from Apnea/Hypopnea index (AHI). The AHI is derived from the total number of apneas and hypopneas divided by the total number of apneas and hypopneas divided by total sleep time.total sleep time.

Apnea is defined as 10 seconds or more of total Apnea is defined as 10 seconds or more of total cessation of airflow despite respiratory effortscessation of airflow despite respiratory efforts

Diagnostic Criteria for OSA.Diagnostic Criteria for OSA.

Current a normal cutoff for the AHI is less Current a normal cutoff for the AHI is less than 5/hour. than 5/hour.

The severity of OSA can be defined based The severity of OSA can be defined based on the AHI.on the AHI.

Mild: AHI = 5Mild: AHI = 5--15 per hour15 per hour

Moderate: AHI = 15Moderate: AHI = 15--30 per hour30 per hour

Severe: AHI >30 per hourSevere: AHI >30 per hour

Examination of Patient with OSA.Examination of Patient with OSA.

The physical examination is frequently The physical examination is frequently unremarkable in OSA, other than the presence unremarkable in OSA, other than the presence of obesity (defined as a body mass index greater of obesity (defined as a body mass index greater than 30 kg/m2) and hypertension. than 30 kg/m2) and hypertension. The clues to the presence of OSA usually come The clues to the presence of OSA usually come from family members who complain of snoring at from family members who complain of snoring at night. night. As in all patients scheduled for surgery, an As in all patients scheduled for surgery, an airway exam is necessary. The upper airway airway exam is necessary. The upper airway should be evaluated in all patients, particularly in should be evaluated in all patients, particularly in nonnon--obese adults with symptoms consistent with obese adults with symptoms consistent with OSAOSA

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Common Features in Patients with Common Features in Patients with Sleep ApneaSleep Apnea

Loud snoring Loud snoring

Disrupted sleep Disrupted sleep Nocturnal gasping and choking Nocturnal gasping and choking

Witnessed apnea Witnessed apnea

Daytime sleepiness and fatigue Daytime sleepiness and fatigue

Diagnosis of OSADiagnosis of OSA

Nocturnal polysomnography is the gold Nocturnal polysomnography is the gold standard for diagnosing obstructive sleep standard for diagnosing obstructive sleep apnea.apnea.

In this technique, multiple physiologic In this technique, multiple physiologic parameters are measured while the patient parameters are measured while the patient sleeps in a laboratory.sleeps in a laboratory.

Diagnosis of OSADiagnosis of OSA

Typical parameters in a sleep study, (Typical parameters in a sleep study, (Nocturnal Nocturnal Polysomnography)Polysomnography) include include eye movement observations (to detect rapideye movement observations (to detect rapid--eyeeye--movement sleep), movement sleep), an electroencephalogram (to determine arousals from an electroencephalogram (to determine arousals from sleep)sleep)chest wall monitors (to document respiratory chest wall monitors (to document respiratory movements)movements)nasal and oral air flow measurements, nasal and oral air flow measurements, an electrocardiograman electrocardiograman electromyogram (to look for limb movements that an electromyogram (to look for limb movements that cause arousals) and oximetry (to measure oxygen cause arousals) and oximetry (to measure oxygen saturation). saturation). Apneic events can then be documented based on chest Apneic events can then be documented based on chest wall movement with no airflow and oxyhemoglobin wall movement with no airflow and oxyhemoglobin desaturationsdesaturations

Sleep vs AnesthesiaSleep vs Anesthesia

SleepSleep Unlike anesthesia, sleep is a state of Unlike anesthesia, sleep is a state of rousablerousableunconsciousnessunconsciousnessAnesthesiaAnesthesia In contrast to sleep, anesthesia is a state of In contrast to sleep, anesthesia is a state of unrousableunrousable

unconsciousness.unconsciousness.

So why are we concerned about the perioperative risks for So why are we concerned about the perioperative risks for morbidly obese patients with sleep apnea?morbidly obese patients with sleep apnea?

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Perioperative Concerns for Morbidly Obese Perioperative Concerns for Morbidly Obese Patients with Obstructive Sleep ApneaPatients with Obstructive Sleep Apnea

Sedative and analgesic agents will aggravate or Sedative and analgesic agents will aggravate or precipitate OSAprecipitate OSAby decreasing pharyngeal tone, by decreasing pharyngeal tone, depressing ventilatory responses to hypoxia and depressing ventilatory responses to hypoxia and hypercapnia hypercapnia inhibiting arousal responses to obstruction, hypoxi a inhibiting arousal responses to obstruction, hypoxi a and hypercapnia.and hypercapnia.The end result is that varying degrees of central The end result is that varying degrees of central respiratory depression can occur.respiratory depression can occur.This problem is compounded in the morbidly obese This problem is compounded in the morbidly obese patient with OSApatient with OSA

The Obesity Hypoventilation SyndromeThe Obesity Hypoventilation Syndrome

The obesity hypoventilation syndrome (OHS) is defined by The obesity hypoventilation syndrome (OHS) is defined by extreme obesity and alveolar hypoventilation during extreme obesity and alveolar hypoventilation during wakefulness. In its classic form, it is also characterized by the wakefulness. In its classic form, it is also characterized by the following findings:following findings:

HypersomnolenceHypersomnolence

DyspneaDyspneaHypoxemia, with resulting cyanosis, polycythemia, and Hypoxemia, with resulting cyanosis, polycythemia, and

plethoraplethoraPulmonary hypertension, leading to right ventricular Pulmonary hypertension, leading to right ventricular

failure and peripheral edemafailure and peripheral edema

The Obesity Hypoventilation SyndromeThe Obesity Hypoventilation Syndrome

Pathophysiology Of Alveolar Hypoventilation. Pathophysiology Of Alveolar Hypoventilation. Alveolar hypoventilation associated with OHS Alveolar hypoventilation associated with OHS occurs as a result of one or both of the following occurs as a result of one or both of the following factors:factors:

An increase in the work of breathing to a level that An increase in the work of breathing to a level that is inconsistent with maintenance of normal alveolar is inconsistent with maintenance of normal alveolar ventilation.ventilation.

A decrease in the "drive" to breatheA decrease in the "drive" to breathe

Arterial Blood Gases and Nocturnal OximetryArterial Blood Gases and Nocturnal Oximetry

Variables OSA OHS

pH 7.42 7.4PaO2 mmHg 75 59PaCO2 mmHg 38 49Sat. O2 % 94 86t Sat. <90% 9 52

Jean Krieger and Emmanuel Weitzenblum, Romain Kessler, Ari Chaouat,Philippe Schinkewitch, Michèle Faller, Simone Casel. 2001 ;120;369-376 Chest.

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The Airway in Morbid ObesityThe Airway in Morbid Obesity

AssessmentAssessment

Who deserves a rapid sequence Who deserves a rapid sequence Intubation?Intubation?

Who deserves an awake intubation?Who deserves an awake intubation?

Assessment of the Airway.Assessment of the Airway.

Limited information in the literature.Limited information in the literature.Most recently:Most recently:

Morbid Obesity and Tracheal Intubation Morbid Obesity and Tracheal Intubation

Jay B. Brodsky, MD*, Harry J. M. Lemmens, MD PhD*,Jay B. Brodsky, MD*, Harry J. M. Lemmens, MD PhD*,John G. BrockJohn G. Brock--Utne, MD PhD*, Mark Vierra, MD, andUtne, MD PhD*, Mark Vierra, MD, andLawrence J. Saidman, MD* Lawrence J. Saidman, MD* (Anesth Analg 2002;94:732(Anesth Analg 2002;94:732––6)6)

Patient Characteristics Stratified by Patient Characteristics Stratified by Problematic and Easy IntubationProblematic and Easy Intubation

Problematic intubation (n = 12) Easy intubation (n = 88) Variable Median 25th pct 75th pct Median 25th pct 75th pct P value Age (yr) 44 39.5 49.5 44 36 51.5 0.9957 Height (cm) 168 159.7 176.9 168 160.3 171.2 0.6471 Weight (kg) 124.8 124 144.1 137 122.3 156.8 0.858 BMI (kg/m2) 46.5 42.5 47.3 48.9 44.2 58.1 0.9393 Neck circumference (cm) 50.5 44.7 54 46 42 48 0.0326 Sternomental distance (cm) 13.5 12.7 16.2 12 14 17 0.4979 Thyromental distance (cm) 9.5 7.7 10 9.5 8 11 0.6556 Mouth opening (cm) 5 4.1 5.2 5.5 4 6.3 0.1284

Neck Circumference and Probability of Problematic Intubation

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Association of Neck Circumference and Other Risk Factors With Problematic Airway Intubati on.

Why Mobidly Obese Patients Merit Special Why Mobidly Obese Patients Merit Special Consideration for Consideration for –– Postoperative Pain Management Postoperative Pain Management

High incidence of myocardial disease and High incidence of myocardial disease and increased susceptibility to postincreased susceptibility to post--operative events.operative events.Changes in respiratory physiology limits Changes in respiratory physiology limits tolerance to opioids and other analgesics that tolerance to opioids and other analgesics that cause respiratory depression.cause respiratory depression.The high incidence of Sleep Apnea and the The high incidence of Sleep Apnea and the Obesity Hypoventilation Syndrome also makes Obesity Hypoventilation Syndrome also makes Morbid Obese patient intolerant of respiratory Morbid Obese patient intolerant of respiratory depression.depression.Challenge for securing the airway outside the Challenge for securing the airway outside the OROR

PostPost--Operative Analgesia for Operative Analgesia for Morbid Obese Patients.Morbid Obese Patients.

•• Intravenous Opioids via Patient Controlled Analgesia or Intravenous Opioids via Patient Controlled Analgesia or health care worker administrationhealth care worker administration

•• Potential ProblemsPotential Problems-- Large amounts of opioids needed for operations with Large amounts of opioids needed for operations with large incisions.large incisions.-- Increased incidence of respiratory depression which may Increased incidence of respiratory depression which may require emergent tracheal intubation.require emergent tracheal intubation.

PrePre--Emptive AnalgesiaEmptive Analgesia

Preemptive analgesia is an antinociceptive Preemptive analgesia is an antinociceptive therapy whose aim is to prevent both peripheral therapy whose aim is to prevent both peripheral and central sensitization, thereby attenuating and central sensitization, thereby attenuating (or, ideally, preventing) the postoperative (or, ideally, preventing) the postoperative amplification of pain sensation. amplification of pain sensation. Treatment can be aimed at the periphery, at Treatment can be aimed at the periphery, at inputs along sensory axons, or at CNS sites inputs along sensory axons, or at CNS sites using single or combinations of analgesics using single or combinations of analgesics applied either continuously or intermittently. applied either continuously or intermittently.

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Pharmacological Agents and Techniques Pharmacological Agents and Techniques of Preemptive Analgesiaof Preemptive Analgesia

Regional anesthesia induced prior to surgical Regional anesthesia induced prior to surgical trauma and continued well into the postoperative trauma and continued well into the postoperative period is effective in attenuating peripheral and period is effective in attenuating peripheral and central sensitization. central sensitization. Pharmacologic agents:Pharmacologic agents:

NMDA (NNMDA (N--methylmethyl--DD--aspartate) antagonistsaspartate) antagonistsalphaalpha--22--receptor agonists receptor agonists NSAIDs (nonNSAIDs (non--steroidal antisteroidal anti--inflammatory drugs)inflammatory drugs)GABA GABA –– like compoundslike compounds

Ketamine As An Adjunct To Opioids For Ketamine As An Adjunct To Opioids For Postoperative AnalgesiaPostoperative Analgesia

Ketamine Ketamine •• Phencyclidine act by blocking NMDA receptorPhencyclidine act by blocking NMDA receptor•• Molecular weight = 238Molecular weight = 238

•• The commercial preparation being a racemic mixture of The commercial preparation being a racemic mixture of both isomers [Sboth isomers [S--(+) and R(+) and R--((——)] in equal amounts)] in equal amounts

•• Ketamine produces profound analgesia, patients keep Ketamine produces profound analgesia, patients keep their eyes open and maintain many reflexes. Patients their eyes open and maintain many reflexes. Patients who receive ketamine alone appear to be in a cataleptic who receive ketamine alone appear to be in a cataleptic

statestate

Ketamine As An Adjunct To Opioids For Ketamine As An Adjunct To Opioids For Postoperative AnalgesiaPostoperative Analgesia

Advantages of using Ketamine:Advantages of using Ketamine:�� In low doses Ketamine reacts synergistically with opioids In low doses Ketamine reacts synergistically with opioids

to produce analgesia. to produce analgesia. �� The use of Ketamine allows for use of decreased The use of Ketamine allows for use of decreased

amounts of opioids.amounts of opioids.

Disadvantages of using ketamine:Disadvantages of using ketamine:�� HallucinationsHallucinations

Bell RF, Dahl JB, Moore RA, Kalso E.Bell RF, Dahl JB, Moore RA, Kalso E. PeriPeri--operative ketamine for acute postoperative ketamine for acute post--operative pain: a quantitative operative pain: a quantitative and qualitative systematic review (Cochrane review) . Acta Anaesthesiol Scand. 2005 Nov;49(10):1405and qualitative systematic review (Cochrane review) . Acta Anaesthesiol Scand. 2005 Nov;49(10):1405--2828

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DexmedetomidineDexmedetomidine As An Adjunct To As An Adjunct To Opioids For Postoperative AnalgesiaOpioids For Postoperative Analgesia

•• An αlpha2An αlpha2--agonist similar to clonidine but with agonist similar to clonidine but with 10 times the potency 10 times the potency

•• Used in the operating room, PACU and ICU for Used in the operating room, PACU and ICU for sedation and analgesia. sedation and analgesia.

•• The drug does not cause significant The drug does not cause significant cardiovascular instability. cardiovascular instability.

•• Dexmedetomidine also possesses several Dexmedetomidine also possesses several properties that may additionally benefit postproperties that may additionally benefit post--operative patients who have opioid tolerance or operative patients who have opioid tolerance or who are sensitive to opioidwho are sensitive to opioid––induced respiratory induced respiratory depression. depression.

Dexmedetomidine As An Adjunct To Dexmedetomidine As An Adjunct To Opioids For Postoperative AnalgesiaOpioids For Postoperative Analgesia

In spontaneously breathing volunteers, In spontaneously breathing volunteers, intravenous dexmedetomidine caused marked intravenous dexmedetomidine caused marked sedation with only mild reductions in resting sedation with only mild reductions in resting ventilation at higher doses.ventilation at higher doses.This quality makes dexmedetomidine an ideal This quality makes dexmedetomidine an ideal analgesic drug for patients who will not tolerate analgesic drug for patients who will not tolerate respiratory depression.respiratory depression.The best use of dexmedetomidine is as an The best use of dexmedetomidine is as an adjunct to opioids.adjunct to opioids.Roger E. Hofer, MD, Juraj Sprung, MD PhD, Michael G. Sarr, MD and Denise J. Wedel, MD. Roger E. Hofer, MD, Juraj Sprung, MD PhD, Michael G. Sarr, MD and Denise J. Wedel, MD. Anesthesia Anesthesia for a patient with morbid obesity using dexmedetomi dine without narcotics.for a patient with morbid obesity using dexmedetomi dine without narcotics. Canadian Journal of Canadian Journal of Anesthesia 52:176Anesthesia 52:176--180 (2005)180 (2005)

What about NSAIDs???What about NSAIDs???

NSAIDs

OPIOIDS

PAIN RELIEF

What about NSAIDs???What about NSAIDs???

Currently the only available NSAID that can be Currently the only available NSAID that can be administered by an IV or IM route is Toradol administered by an IV or IM route is Toradol (Ketorolac)(Ketorolac)ToradolToradol 60 mg IM or 30 mg IV is equivalent to 60 mg IM or 30 mg IV is equivalent to Morphine 12 mg IM or 6 mg of Morphine IV.Morphine 12 mg IM or 6 mg of Morphine IV.ToradolToradol has longer duration of action than has longer duration of action than Morphine and does not cause respiratory Morphine and does not cause respiratory depression.depression.Am J Obstet Gynecol. 2003 Dec;189(6):1559-62.

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What about NSAIDs???What about NSAIDs???Problems with Toradol:Problems with Toradol:

•• Inhibits platelet aggregationInhibits platelet aggregation

•• May increase bleedingMay increase bleeding•• May cause ulceration of the gastric May cause ulceration of the gastric

mucosamucosa•• May impair renal functionMay impair renal function

Gabapentin.Gabapentin.

Used as adjunct analgesics for the Used as adjunct analgesics for the treatment of perioperative pain.treatment of perioperative pain.There have been several studies which There have been several studies which have shown that the anticonvulsant have shown that the anticonvulsant gabapentin is very effective as an adjunct gabapentin is very effective as an adjunct analgesia and that use of the drug reduces analgesia and that use of the drug reduces the opioid requirement after several types the opioid requirement after several types of surgeries including mastectomies and of surgeries including mastectomies and hysterectomies.hysterectomies.

Gabapentin.Gabapentin.Gabapentin is structurally related to the neurotransmitter, Gabapentin is structurally related to the neurotransmitter,

GABA (gammaGABA (gamma--aminobutyric acid).aminobutyric acid).

�� Gabapentin does not modify GABAGabapentin does not modify GABAαααααααα or GABAor GABAββββββββradioligand bindingradioligand binding

�� Gabapentin is not converted metabolically into GABA or Gabapentin is not converted metabolically into GABA or a GABA agonist, nor is it an inhibitor of GABA uptake or a GABA agonist, nor is it an inhibitor of GABA uptake or degradation. degradation.

�� The mechanism of action of gabapentin has been The mechanism of action of gabapentin has been established as binding to the established as binding to the α2δα2δ sub unit of the sub unit of the presynaptic voltage gated calcium channel in spinal presynaptic voltage gated calcium channel in spinal nociceptive neurons. Binding results in inhibition of nociceptive neurons. Binding results in inhibition of calcium influx and a commensurate reduction in release calcium influx and a commensurate reduction in release of excitatory transmitters in the pain pathway.of excitatory transmitters in the pain pathway.

PostPost--Operative Care of the Morbidly Obese Operative Care of the Morbidly Obese PatientPatient

Patients with challenging airways or with airway Patients with challenging airways or with airway edema should be cared for in the ICU, these edema should be cared for in the ICU, these patients may merit postpatients may merit post--operative intubation.operative intubation.For morbidly obese patients receiving postFor morbidly obese patients receiving post--operative opioid analgesia, a step down unit with operative opioid analgesia, a step down unit with pulse oximetry may be helpful.pulse oximetry may be helpful.Reduction of use of opioid analgesia and Reduction of use of opioid analgesia and increasing the use of nonincreasing the use of non--opioid analgesia may opioid analgesia may be helpful.be helpful.

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Same Day SurgerySame Day Surgery

Should patients with morbid obesity and Should patients with morbid obesity and obstructive sleep apnea be scheduled at obstructive sleep apnea be scheduled at same day surgery centers?same day surgery centers?

No unanimous consensus, however, for No unanimous consensus, however, for certain procedures which involve local certain procedures which involve local anesthesia, same day surgery may be anesthesia, same day surgery may be appropriate.appropriate.

Increased postoperative monitoring may be Increased postoperative monitoring may be necessary.necessary.

Consultant Opinions Regarding Procedures That May Consultant Opinions Regarding Procedures That May Be Performed Safely on an Outpatient Basis for Be Performed Safely on an Outpatient Basis for

Patients at Increased Perioperative Risk from OSAPatients at Increased Perioperative Risk from OSA

Type of Surgery Anesthesi a Type of Surgery Anesthesi a Consultant Consultant OpinionOpinion

Superficial surgery/local or regional anesthesia Superficial surgery/local or regional anesthesia Ag reeAgreeSuperficial surgery/general anesthesia Superficial surgery/general anesthesia EquivocalEquivocalAirway surgery (adult, e.g., UPPP)Airway surgery (adult, e.g., UPPP) Disagree Disagree Tonsillectomy in children less than Tonsillectomy in children less than DisagreeDisagree3 years old3 years oldTonsillectomy in children greater than 3 years old Tonsillectomy in children greater than 3 years old EquivocalEquivocalMinor orthopedic surgery/local or regional anesthes ia Minor orthopedic surgery/local or regional anesthes ia AgreeAgreeMinor orthopedic surgery/general anesthesia Minor orthopedic surgery/general anesthesia Equivoc alEquivocalGynecologic laparoscopy Gynecologic laparoscopy EquivocalEquivocalLaparoscopic surgery, upper abdomen Laparoscopic surgery, upper abdomen Disagree Disagree Lithotripsy Lithotripsy AgreeAgree

Anesthesiology 2006; 104:1081Anesthesiology 2006; 104:1081––93 © 2006 American Society of Anesthesiologists, Inc. Lippincott Williams & Wilkins, Inc. Practice93 © 2006 American Society of Anesthesiologists, Inc. Lippincott Williams & Wilkins, Inc. Practice Guidelines for the Perioperative Management of Guidelines for the Perioperative Management of Patients with Obstructive Sleep ApneaPatients with Obstructive Sleep Apnea

In SummaryIn SummaryPerioperative management of the patient with Perioperative management of the patient with morbid obesity should include:morbid obesity should include:Detailed preoperative assessment.Detailed preoperative assessment.Using good judgment with regards to the type of Using good judgment with regards to the type of procedures performed in an outpatient setting procedures performed in an outpatient setting Limiting the use of opioids in the operating theater Limiting the use of opioids in the operating theater and use of preand use of pre--emptive analgesia.emptive analgesia.Post operative use of devices such as CPAP Post operative use of devices such as CPAP

ConclusionConclusionPatients with morbid obesity Patients with morbid obesity are a challenge with significant are a challenge with significant risk factors and hence good risk factors and hence good preoperative preparation is preoperative preparation is important.important.Intraoperative management Intraoperative management should include a reduction of should include a reduction of opioid use in favor of nonopioid use in favor of non--opioid analgesics.opioid analgesics.Careful postCareful post--operative operative management is importantmanagement is importantPain management is key to Pain management is key to recovery from surgery and recovery from surgery and individuals may have different individuals may have different thresholds for pain, every effort thresholds for pain, every effort should be made to reduce pain should be made to reduce pain after surgery.after surgery.