Obesity and Anesthesia

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all causes in obese Goes up 13x Disclaimer I am obligated to disclose the following affiliations: Baxter Pharmaceutical Percent Body Fat Percent Body Fat Increases With Aging 3 2 1 Body Weight

1 Obesity and Anesthesia Anthony Chipas PhD, CRNA Anesthesia & Educational Services, LLC Too Fat? Researchers Say All Americans Are in Danger of Becoming Obese % overweight Americans increased by 33% last 2 years More than 25 % children today are overweight or obese 6% increase risk of death from all causes in obese Goes up 13x Disclaimer I am obligated to disclose the following affiliations: Baxter Pharmaceutical Percent Body Fat Percent Body Fat Increases With Aging Body Weight Percent Body Fat 1 5 Body Weight (kg) Age (Years) Adapted from Prentice AM et al. Obesity Rev. 21;2: BMI Increases with Age in White and Black Men, Particularly in Recent Times 3 28 Body Mass Index (BMI) Values White Men Black Men Born Years of Age Wang YC et al. Obesity. 27;15:

2 BMI Increases with Age in White and Black Women, Particularly in Recent Times Body Mass Index (BMI) Values Black Women White Women Born BRFSS, Years of Age No Data <1% 1% 14% Wang YC et al. Obesity. 27;15: BRFSS, 1985 BRFSS, 1988 No Data <1% 1% 14% No Data <1% 1% 14% BRFSS, 1986 BRFSS, 1989 No Data <1% 1% 14% No Data <1% 1% 14% 2

3 BRFSS, 199 BRFSS, 1993 No Data <1% 1% 14% No Data <1% 1% 14% 15% 19% BRFSS, 1991 BRFSS, 1994 No Data <1% 1% 14% 15% 19% No Data <1% 1% 14% 15% 19% BRFSS, 1992 BRFSS, 1995 No Data <1% 1% 14% 15% 19% No Data <1% 1% 14% 15% 19% 3

4 BRFSS, 1996 BRFSS, 1999 No Data <1% 1% 14% 15% 19% No Data <1% 1% 14% 15% 19% 2% BRFSS, 1997 BRFSS, 2 No Data <1% 1% 14% 15% 19% 2% No Data <1% 1% 14% 15% 19% 2% BRFSS, 1998 BRFSS, 21 No Data <1% 1% 14% 15% 19% 2% No Data <1% 1% 14% 15% 19% 2% 24% 25% 4

5 BRFSS, 22 BRFSS, 25 No Data <1% 1% 14% 15% 19% 2% 24% 25% No Data <1% 1% 14% 15% 19% 2% 24% 25% 29% 3% BRFSS, 23 BRFSS, 26 No Data <1% 1% 14% 15% 19% 2% 24% 25% No Data <1% 1% 14% 15% 19% 2% 24% 25% 29% 3% BRFSS, 24 BRFSS, 27 No Data <1% 1% 14% 15% 19% 2% 24% 25% No Data <1% 1% 14% 15% 19% 2% 24% 25% 29% 3% 5

6 BRFSS, 28 BRFSS, 29 BRFSS, 21 6

Obesity Trends in Children Cost of overweight/obesity in the USA per year Total cost: US$122,9,, Direct cost: US$ 64,1,, Indirect cost: US$ 58,8,,

consumer dollars spent in the early 199s on all efforts at weight loss or weight maintenance Low-calorie foods Artificially sweetened products

Kingdom 51% Brazil 36% China 15% Malaysia 27% Too Fat?

7 Obesity Trends in Children Cost of overweight/obesity in the USA per year Total cost: US$122,9,, Direct cost: US$ 64,1,, Indirect cost: US$ 58,8,, Annual expenditure on weight-loss products and services Americans spend $33 billion annually on weightloss products and services This figure represents consumer dollars spent in the early 199s on all efforts at weight loss or weight maintenance Low-calorie foods Artificially sweetened products Memberships to commercial weight-loss centers Diet publications Prevalence of Overweight Adults United States 61% Australia 59% Russia 54% United Kingdom 51% Brazil 36% China 15% Malaysia 27% Too Fat? Blamed on Environment Too much food available Social situations encourage overeating Restaurants compete by offering bigger servings Technology makes it possible to avoid exercise Winston-Salem Journal, Source: WHO, Preventing and managing a global epidemic,

Childhood Obesity Facts Only 42% of the youth in these grade levels are meeting current physical activity recommendation levels. Only 18% eat fruits and vegetables five or more times a day.

8 Childhood Obesity Facts Only 42% of the youth in these grade levels are meeting current physical activity recommendation levels. Only 18% eat fruits and vegetables five or more times a day. Almost half drink at least one non-diet soda each day. Thirty-eight percent watch three or more hours of television each day. Hardee s Monster Burger Definitons It s All About Size! Obesity defined in relation to ideal body weight (IBW), or in relation to height using indices such as the body mass index (BMI). BMI is weight (kg)/ height (m) 2 (wt/ht2). i.e. 7-kg, 1.7-m patient has a BMI of 24. Patients who weigh 2% IBW or have a BMI than 28 are regarded as obese. About 1/3 U.S. population meets this definition of obesity; prevalence of individuals with a BMI > 28 has 8% in the past 15 years. Morbidly obese, weigh 45 kg above IBW or have a BMI of greater than % of the U.S. population. CHEESEBURGER 2 Years Ago Today BMI = Ideal Body Weight Wt (kg) Ht (M 2 ) 333 calories 59 calories BMI = < 25 normal overweight 3-4 obese 4 55 morbid obesity > 55 super morbidly obese 8

9 BMI isn t the only thing! Shaquille O Neill BMI 46.3 kg/m = 2.16 m 325 lb= kg Overweight, Obesity, and Health Risk Obesity-Associated Diseases and Conditions Type 2 diabetes Coronary artery disease Hypertension Sleep apnea, pulmonary dysfunction Stroke Gallbladder disease Liver disease Musculoskeletal disease Reproductive function Cancer Degenerative disc disease GERD Arch Int Med 16:98;2 Age of Death Respiratory System Average US Morbidly obese 8s 5s O 2 and CO 2 ; BMR, because it is related to body surface area, is usually normal. Contributing to the increased O 2 metabolic activity of fat, in energy expenditure for locomotion and breathing. With exercise, O 2 and CO 2 more sharply than in people of normal body weight, as does the oxygen cost of respiration, implying respiratory muscle inefficiency. Respiratory System Pathophysiology of Obesity Mass loading of the chest wall and abdomen by fat alters performance of the respiratory system. Upright position, expiratory reserve volume and functional residual capacity (FRC) TV may fall within the range of closing capacity ventilation perfusion (V/Q) abnormalities, or frank right-to-left shunt, with ensuing hypoxemia Supine position, FRC often falls further. 9

Respiratory System Fat mass loading chest wall compliance, with lung compliance remaining unaffected and respiratory resistance increased. Usual clinical tests of respiratory function (e.g., forced vital capacity, forced expiratory volume in 1 second [FEV1], and peak expiratory flow rate) are usually normal in the healthy obese patient.

Pertinent to the CRNA Cardiovascular Disorders Systemic hypertension Pulmonary hypertension Increased blood volume Increased cardiac output Cardiomegaly Increased incidence angina and sudden death

10 Respiratory System Fat mass loading chest wall compliance, with lung compliance remaining unaffected and respiratory resistance increased. Usual clinical tests of respiratory function (e.g., forced vital capacity, forced expiratory volume in 1 second [FEV1], and peak expiratory flow rate) are usually normal in the healthy obese patient. The Ultimate Challenge Perioperative Management of a 43 kg (946 lb) Patient With Pickwickian Syndrome Newman GG: Anesth Analg 198 Effect of Obesity on Function Residual Capacity Physiological Changes Pertinent to the CRNA Cardiovascular Disorders Systemic hypertension Pulmonary hypertension Increased blood volume Increased cardiac output Cardiomegaly Increased incidence angina and sudden death Increased thromboembolic complications Adams & Murphy, BJA 85(1):91, 2 Respiratory System Most obese patients maintain a sufficient minute ventilation (E) to remain normocarbic and preserve a normal response to carbon dioxide challenge. obesity, intercurrent lung disease, and the changes wrought by pulmonary hypertension deteriorate to the obesity hypoventilation syndrome Loss of hypercarbic drive, Sleep apnea, Hypersomnolence, and Pickwickian syndrome hypercarbia, hypoxemia, polycythemia, hypersomnolence, pulmonary hypertension, and biventricular failure. 1

Gastrointestinal System Faster gastric emptying times Up to 75% greater gastric volume Residual volume for a given period of time is larger in obese individuals Weight loss associated with a

patient fully awake continue to be advocated Gastrointestinal System of hiatal hernia and a linear increase in intraabdominal pressure with increasing weight.

Prevalence of hepatic dysfunction is particularly high in patients who have undergone intestinal bypass operations.

11 Gastrointestinal System Faster gastric emptying times Up to 75% greater gastric volume Residual volume for a given period of time is larger in obese individuals Weight loss associated with a significant slowing in gastric emptying Aspiration prophylaxis H2 receptor antagonists, antacids and prokinetic agents, rapid sequence induction with cricoid pressure tracheal extubation with the patient fully awake continue to be advocated Gastrointestinal System of hiatal hernia and a linear increase in intraabdominal pressure with increasing weight. 9% of fasted morbidly obese patients presenting for elective surgery have a gastric fluid volume in excess of 25 ml and a gastric fluid ph of less than 2.5. risk for aspiration. Prevalence of hepatic dysfunction is particularly high in patients who have undergone intestinal bypass operations. Preoperative Assessment Should be aware of your own feelings, attitudes, and prejudices toward obesity and avoid condescension. Obese patients should be evaluated in a thorough, nonjudgmental fashion, with particular emphasis on the difficulties that obesity presents to the anesthesiologist. Preoperative Assessment Respiratory The clinical history should seek to identify symptoms indicative of severe degrees of: respiratory disease (e.g., orthopnea), obesity hypoventilation syndrome, or sleep apnea syndrome Elicit any history of upper airway obstruction. Because the degree of respiratory compromise in the postoperative period is often pronounced, imperative to optimize the patient s pulmonary status. 11

Patients with such histories may present formidable airway difficulties.

12 Airway Preoperative Evaluation A history of airway difficulties during previous anesthetics and operations. The patient should be questioned about symptoms of: obstructive sleep apnea (excessive nocturnal snoring, with or without apneic episodes). Patients with such histories may present formidable airway difficulties. Patient will die before paralysis of 1 mg/kg succinylcholine wears off Airway Flexion of the cervical spine and the atlantoaxial joint limited by numerous chins and by thoracic wall or breast fat. Extension of these joints may be limited by low cervical or upper thoracic fat pads. Mouth opening restricted by submental fat. Fleshy cheeks, a large tongue, and copious flaps of palatal, pharyngeal, and supralaryngeal soft tissue may narrow the airway. Morbidly obese have a high prevalence of obstructive apnea syndrome. Tidal volume breathing 3-5 minutes for maximal preoxygenation =ETO 2 > 9%, ETN 2 <5% Mask held by straps &/or hand Reservoir bag moving on I&E Good capnograph waveform 8 deep breaths in 2 minutes Preoxygenation Denitrogenation 4 deep breaths in 3 seconds Only used if time limited or urgent FGF 5L/min; F i O 2 = 1% Nimmagadda. Anesth. Analgesia 21;92: Denitrogenation Function of Preoxygenation Can t use same pillow Functional Residual Capacity Driving Pressure P A O 2 = 149 mmhg P A N 2 = 564 mmhg 79% P A O 2 = 149 mmhg (23 ml *.21)/2 ml/min = 2.5 min Functional Residual Capacity Driving Pressure P A O 2 = 713 mmhg P A N 2 < 5% P A O 2 = 713 mmhg (23 ml * 1.)/2 ml/min = 11.5 min P A O 2 = (Pb - P H2 ) * FiO 2 PaO 2 = 4 mmhg PaO 2 = 8 mmhg PaO 2 = 4 mmhg PaO 2 = 1 mmhg FiO 2 = 21% FiO 2 = 1% 12

13 Blankets & pillows under shoulders Positioning in the Obese Patient Pi Pillow Pi Pillow 13

Troop Pillow General Anesthesia Volatile anesthetic agents Older agents New agents Isoflurane Pharmacologic Changes Physiologic changes that affect drug distribution include: CO blood volume lean

Lipid soluble drugs volume of distribution. Albumin binding of drugs. Pharmacologic Changes Changes in hepatic function affect drug clearance.

14 Troop Pillow General Anesthesia Volatile anesthetic agents Older agents New agents Isoflurane Pharmacologic Changes Physiologic changes that affect drug distribution include: CO blood volume lean body mass organ size, and fat mass. Water-soluble compounds have smaller distribution volumes than lipophilic compounds and their distribution is less affected by obesity. Lipid soluble drugs volume of distribution. Albumin binding of drugs. Pharmacologic Changes Changes in hepatic function affect drug clearance. No changes in Phase 1 metabolism (oxidation, reduction, hydrolysis). Phase II conjugation pathways (glucuronidation and sulfation) appear to be cleared faster in the obese. renal glomerular filtration and tubular secretion are increased in the obese, and renally excreted drugs may need increased dosages. Inhaled Agents: Blood/gas Partition Coefficient (Solubility).42 % (Fast onset) Nitrous Oxide.47 % (Fast onset).69 % (Medium) Isoflurane 1.43 % (Medium) Ethrane 1.9 % (Medium) Halothane 2.4 % (Slow) Penthrane 13. % (Very slow) 14

Implications of Low Solubility More rapid wash-in Greater anesthetic control and precision More rapid emergence from anesthesia Potentially greater economy through more rapid recovery May eliminate N

1.2 1. 1.2 Muscle 2. 3.1 2.9 3.4 1.2 Eger EI II. (Suprane ). A Compendium and Reference. 1993. Eger EI II. (Suprane ). A Compendium and Reference. 1993. Eger EI II. In: Miller RD, ed. Anesthesia.

2 Isoforane Halothane Return to Normal Activity Group of patients undergoing outpatient gynecological surgery Discharge time compared to 3.5 hrs vs 3.

15 Implications of Low Solubility More rapid wash-in Greater anesthetic control and precision More rapid emergence from anesthesia Potentially greater economy through more rapid recovery May eliminate N 2 O without kinetic disadvantage Human Tissue:Blood Partition Coefficients Isoforane Halothane N 2 O Fat Brain Heart Liver Kidney Muscle Eger EI II. (Suprane ). A Compendium and Reference Eger EI II. (Suprane ). A Compendium and Reference Eger EI II. In: Miller RD, ed. Anesthesia. 5th ed. 2. Inspired and Alveolar Anesthetic Concentrations 1 N 2 O.8 F A /F I Isoforane Halothane Return to Normal Activity Group of patients undergoing outpatient gynecological surgery Discharge time compared to 3.5 hrs vs 3. hrs Number who returned to normal activity on first postoperative day compared to 15 vs Minutes of Administration Yasuda et al. Anesth Analg Mahmoud et al. or sevoflurane for gynecological day-case anaesathesia with spantaneous respiration? Anaesthesia, 21; 56: Terminal Decrement Now for the rest of the story. 1 Enflurane 8 9% Isoflurane 6 Decrement Time (min) Duration of Anesthetic Administration (min) Bailey JM. Anesth Analg. 1997;85:

16 Does Fat Solubility Affect Recovery from Anesthesia? Reduces Time to Extubation Compared to According to a meta-analysis by Dexter: reduces the average extubation time and the variability of extubation time by 2% 25% relative to sevoflurane. *Vessel-rich group: brain, heart, liver, kidney, endocrine glands. Eger. In: Anesthesia, 5th ed. 2:74; Philip. Gas Man. 22; Roizen In: Anesthesia. 5th ed. 2:93; Sollazzi et al. Obes Surg. 21;11:623; Cork et al. Anesthesiology. 1981;54:31; Torri et al. Minerva Anestesiol, 22; 68:523. Dexter F et al. Anesth Analg. 21;11: Extubation Criteria: Emergence Patient awake, alert, following commands Patient able to protect airway Patient cardiovascularly stable Muscle relaxants adequately reversed Sustained head lift >5 seconds A More Rapid Awakening May Save PACU Time 1 Minutes to PACU Discharges after.85 MAC-Hours of Anesthesia for Laparoscopic 5 Cholecystectomy (median±quartiles) P=.4 Adapted from Fanelli G et al. Eur J Anaesthiol. 26;23: Emergence Extubation criteria should be met, especially if obese Place in a 45º sitting position to improve oxygenation Provide supplemental oxygen before transporting to the PACU Cautious titration of narcotics Consider epidural or block for postop pain management BMI Affects Recovery of Pharyngeal Function More With Than With Time From Anesthetic Discontinuation to First Ability to Swallow by BMI Time 2, (seconds) From Anesthetic Discontinuation Until First 1, Ability to Swallow* (Note: 1 seconds = 17 minutes) * Regarding Swallowing: Administering water to patients after anesthetic discontinuation is not a standard of care. Important Risk Information: These inhalation agents should be administered by trained personnel in adequately equipped anesthetizing environment, including oxygen enrichment and circulatory resuscitation. P=.2 P= Body Mass Index (kg/m 2 ) McKay RE et al. Br J Anaesth. 21;14:

17 The PINOCCHIO Study Group Bilotta F et al and the PINOCCHIO Study Group. Early postoperative cognitive recovery and gas exchange patterns after balanced anesthesia with sevoflurane or desflurane in overweight and obese patients undergoing craniotomy: a prospective randomized trial. J Neurosurg Anesthesiol. 29;21: Extubation Aldrete 9 Early Recovery Faster With P<.1 for both desflurane vs sevoflurane comparisons These inhalation agents should be administered by trained personnel in adequately equipped anesthetizing environment, including oxygen enrichment and circulatory resuscitation Minutes after Anesthesia Stopped (Mean±SD) Adapted from Bilotta F et al. J Neurosurg Anesthesiol. 29;21: PINOCCHIO: Demographics and Study Design Two groups of 28 patients (average BMI 28) With supratentorial expanding lesions Anesthesia was induced with 2 mg/kg propofol and 2 mcg/kg fentanyl* Randomly assigned to desflurane versus sevoflurane At BIS of 4 5 *Added boluses of fentanyl were provided if necessary. Bilotta F et al. J Neurosurg Anesthesiol. 29;21: Later Recovery also Faster With Short Orientation Memory Concentration Test Score (Maximum Score 28; Mean±SD) * Control Minutes after Anesthesia Stopped * *P<.5 Serious adverse events including cardiac arrest and respiratory arrest have been reported. Bilotta F et al. J Neurosurg Anesthesiol. 29;21: PINOCCHIO: Results No difference in demographics or hemodynamics For approximately 26 minutes of anesthesia in each group Fentanyl dosage not different between groups (498 mcg ± 56 versus 51 mcg ± 45) Measured various recovery functions (observerblinded) Recovery of Normal Ventilation Faster With PaCO 2 (Mean±SD) * * Pre Minutes after Anesthesia Stopped *P<.5 Bilotta F et al. J Neurosurg Anesthesiol. 29;21: Bilotta F et al. J Neurosurg Anesthesiol. 29;21:

18 Greater Acidosis after 7.45 ph (Mean±SD) *P<.5) * Control * * Minutes after Anesthesia Stopped *P<.5 Bilotta F et al. J Neurosurg Anesthesiol. 29;21: Effect of BMI on Parameters of Recovery: vs McKay RE, Malhotra A, Cakmakkaya OS, Hall KT, McKay WR, Apfel CC. Effect of increased body mass index and anaesthetic duration on recovery of protective airway reflexes after sevoflurane vs desflurane. Br J Anaesth. 21;14: Clinical Implications Faster initial recovery allows earlier neurological examination Earlier normal respiration (CO 2 ) may have a lesser effect on intracranial pressure Bilotta F et al. J Neurosurg Anesthesiol. 29;21: Study Design Two groups of 6 surgical patients randomly assigned to desflurane or sevoflurane using LMA for airway management Each group consisted of subgroups of 2 patients with BMI ranges of 18-24, 25-29, and 3 Patients received 2 mg of midazolam pretreatment Anesthesia was induced with lidocaine (-1.5 mg/kg ), propofol (1-3 mg/kg ), and fentanyl as necessary Neuromuscular blocking agents were avoided in all cases An observer, blinded to anesthetic assignment, noted study endpoint responses McKay RE et al. Br J Anaesth. 21;14: Recovery in Bariatric Patients More rapid return of cognitive function More rapid return to wakefulness and dexterity skills Increase in patient mobility Less nausea and vomiting Juven et al, A & A, 1997; 85: Study Endpoints and Their Clinical Significance T1 Time from discontinuation of anesthesia until first response to command Reflects the time to the earliest patient response following discontinuation of anesthesia T2 Time from first response to command until first demonstrated ability to swallow* Allows a comparison between anesthetics starting at the same level of recovery, ie, awareness T3 Time from discontinuation of anesthesia until first demonstrated ability to swallow* Reflects the overall time before the patient can demonstrate the more physiologically rigorous endpoint of swallowing * Regarding Swallowing: Administering water to patients after anesthetic discontinuation is not a standard of care. McKay RE et al. Br J Anaesth. 21;14:

19 Study Hypotheses and Rationale Previous studies have shown that volunteers and patients awaken more rapidly from anesthesia with desflurane than with sevoflurane At least in part this occurs because of the lesser solubility of desflurane in blood and tissues Fat acts as an anesthetic reservoir and fat adjacent to viscera or muscle may take up anesthetic by intertissue diffusion In contrast to bulk fat, anesthetic content in fat receiving anesthetic by intertissue diffusion is much greater and may release anesthetic earlier in recovery Given the inter-anesthetic differences in fat/gas and muscle/gas partition coefficients, increases in BMI might increase the interface area for fat adjacent to viscera or muscle. The hypotheses tested by the investigators were that, for sevoflurane, patients with large BMI values or those with a longer duration of anesthesia would show delayed recoveries compared to similar patients receiving desflurane For T3 is Independent of BMI for BMI Time (s) from 2 anesthetic discontinuation 15 until first ability to swallow 1 (T3) 1 s = 17min P=.2 1 P<.1 5 P=.12 (not P=.3 significant ) BMI (kg m 2 ) BMI (18 35kg m 2 ) McKay RE et al. Br J Anaesth. 21;14: * Regarding Swallowing: Administering water to patients after anesthetic discontinuation is not a standard of care. McKay RE et al. Br J Anaesth. 21;14: Results Time to Swallow Response Was Almost Independent of BMI for Compared to sevoflurane, desflurane demonstrated almost no dependence between the time from discontinuation of anesthesia and the ability to swallow for: BMI Duration of anesthesia For sevoflurane, prolonged duration of anesthesia and greater BMI delay airway reflex recovery McKay RE et al. Br J Anaesth. 21;14: Percent of patients 6 able to swallow 4 2 * BMI BMI 3 BMI * *P<.1 vs desflurane P<.5 sevoflurane for BMI vs BMI Minutes after response to command * BMI BMI 3 Minutes after response to command McKay RE et al. Br J Anaesth. 21;14: Time to Swallow* Shorter for Than for 3 P<.1 sevoflurane vs desflurane 25 Time form anesthetic 2 discontinuation until first 15 ability to swallow 1 (T3) (mean±sd) 1 s = 17 5 min BMI (kg m -2 ) * Regarding Swallowing: Administering water to patients after anesthetic discontinuation is not a standard of care. Adapted from McKay RE et Anaesth. al. Br J 21;14: Time (s) from anaesthetic discontinuati on to first ability to swallow (T3) 1 s = 17min T3 is Independent of MAC-Hours of Anesthesia for P=.441 (not significant) P< MAC Hours McKay RE et al. Br J Anaesth. 21;14:

20 Clinical Implications of this Study Compared to sevoflurane, recovery response for desflurane was essentially independent of BMI and duration of anesthesia The observed difference in time to recovery of protective airway reflex differs more than the sevoflurane and desflurane blood/gas and tissue/blood solubilities alone would suggest The time to airway reflex recovery vs BMI curves suggest that anesthetic partitioning of sevoflurane and desflurane are better reflected by fat/gas than lean tissue/gas coefficients This relative lack of variability in important recovery parameters demonstrates that desflurane allows for more predictable patient recovery responses than does sevoflurane Postoperative Care Respiratory Function Postoperative hypoxemia is a universal hazard. Supplemental oxygen should be given during transport from the operating room to the recovery room. Respiratory monitoring should be particularly aggressive in the recovery room and should include pulse oximetry or arterial blood gas monitoring, or both. After intra-abdominal operations, arterial hypoxemia may last 4 6 days and is of greater magnitude with vertical than with horizontal incisions. Hypoxemia minimized by having patients sit in bed. Regional McKay RE et al. Br J Anaesth. 21;14: Emergence in Bariatric Patients clears quicker than N 2 O Less chance for diffusion hypoxia at end of case if nitrous oxide not on board Less postoperative hypoxemia Avoid Nitrous Oxide or turn off early Juven et al. A & A, 2, 91: Postoperative Complications Pulmonary Hypoxemia Atelectasis Pneumonia Thrombo-Embolic Thrombophlebitis DVT Pulmonary embolus Wound Infection Quicker Bariatric Emergence Can move self from OR table Less back stress on staff Less risk for aspiration Less window for nausea Less OR time (expensive) Anesthesia Provider looks good Staff feels CRNA is a good practitioner Patient feels more awake and can be discharged quicker Postoperative Care Analgesia Use of opioid analgesics can be hazardous in obese patients. If an epidural catheter was placed for operative anesthesia, it may be used as the route for injecting either local anesthetic or opioid to provide postoperative analgesia. Epidural opioid analgesia may result in delayed respiratory depression. Because of the difficulty of maintaining or securing the airway in obese patients, those receiving epidural opioids should probably be in a closely monitored environment (e.g., an intensive care unit) until the potential for such a complication has passed. 2

21 It s All About Silos OR Costs Recovery Costs Anesthesia Costs Questions? Acquisition costs are not everything. Our pharmacists asked if we could use more Forane! I ll give up my new agents when the pharmacists start compounding their own medication again! 21

Inhalational Agents in Bariatric Procedures

Inhalational Agents in Bariatric Procedures Overweight The term overweight signifies an excess body weight when compared to established standards. This weight may derive from muscle, bone, fat, and/or