ISSUES UNIQUE TO WOMEN/BARIATRIC SURGERY
From Perioperative Management, sponsored by Johns Hopkins University School of Medicine
| PERIOPERATIVE MANAGEMENT ISSUES UNIQUE TO WOMEN —Kimberly S. Peairs, MD, Assistant Professor of
Medicine, Johns Hopkins University School of Medicine, Baltimore
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| Women and coronary artery disease (CAD): risk factors—diabetes most powerful predictor of CAD in women (associated
increase in risk much higher than in men); hypertension, decreased high-density lipoprotein (HDL), hypertriglyceridemia,
and tobacco use increase risk in women more than in men; risk for cardiovascular event more than doubles in
women with diabetes, compared to women without diabetes; women with diabetes (especially young women) have risk
for coronary disease similar to that of men
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| Presentation and outcome: atypical (eg, vasospastic, microvascular, nonischemic) chest pain more common in women than
men; nonischemic disease (eg, acid reflux) causes chest pain more commonly in women; ischemia associated with atypical
features (eg, nausea, vomiting, neck pain, pain not relieved by rest, heart palpitations) more common in women; substernal
pressure (although occurring less frequently than in men) highly suggestive of CAD; retrospective questionnaire of patients
with acute myocardial infarction (MI) revealed common prodromal symptoms include significant fatigue, sleep disturbance,
and shortness of breath; only 29% reported new-onset chest pain in month before MI; presentation of acute coronary
syndrome—women typically older than men at time of presentation and more likely to have diabetes, hypertension, and history
of MI; unstable angina more common than MI in women; ST-elevation MI less common in women than men, but
women with ST-elevation MI have higher rate of mortality during first 30 days and may have higher risk for subsequent MI;
severe disease as revealed by angiography (eg, triple-vessel or high left main disease) less common in women; age of
onset—10 yr later in women (10 yr after menopause); in-hospital mortality after MI—16.7% in women; 11.5% in men;
among patients <50 yr of age, mortality rate in women twice that of men
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| CAD in young women: recognition—later than in men (patient may ignore symptoms; physician may delay referral); anatomic
and biologic factors—young women with CAD may have different type of vessel disease or may lack protective effect
of estrogen that premenopausal women normally have
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| Assessment of CAD in women: graded exercise stress test less sensitive in women because of lower prevalence of multivessel
and left main diseases; false-positive results also more common (women have more variability in baseline heart rhythm);
note—if criteria for adequate walking exercise stress test met, normal results sufficient to exclude significant coronary disease;
speaker recommends stress echocardiography or pharmacologic stress echocardiography (eg, with dobutamine) for patients
with decreased functional capacity
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| Heart failure in women: prevalence increases with age (in both sexes); longer life spans lead to higher lifetime risk in
women; systolic hypertension greatest risk factor in women; diastolic dysfunction (ie, heart failure with normal ejection
function) more common in women than men; question about role of hormones in cardiac hypertrophy and associated diastolic
dysfunction seen in older women
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| Oral contraceptives (OCs): absolute risk for thromboembolic events low; greatest risk during first year of use (highest during
first 4 mo); risk increases with higher doses of estrogen, use of third-generation progestins, obesity, and hereditary
thrombophilia (eg, factor V Leiden, mutations of prothrombin 20210A); obese women taking OCs have 10-fold increase
in risk for thromboembolism; risk for MI and stroke increases with concomitant use of tobacco or hypertension; perioperative
management—consider discontinuing medication 4 to 6 wk before surgery associated with high risk for thromboembolism
(eg, hip or knee arthroplasty) in obese women or smokers
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| Selective estrogen receptor modulators (SERMs): raloxifene (Evista) and tamoxifen associated with 2- to 3-fold increase in
risk for venous thrombosis; potentially beneficial effects include decreased levels of low-density lipoproteins (LDL), lipoprotein
A, and homocysteine (especially with raloxifene); perioperative management—discontinue raloxifene 4 to 6
wk before surgery with high risk for thromboembolism; consult oncologist before discontinuing tamoxifen
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| Hormone replacement therapy (HRT): Heart and Estrogen/Progestin Replacement Study (HERS) looked at postmenopausal
women with known coronary disease; patients on HRT had increase in coronary events and venous thromboembolism in
first year; no benefit from HRT established; Women’s Health Initiative (WHI; large placebo-controlled primary prevention
study), found women taking estrogen and progesterone had increased risk for nonfatal MI, cardiac death, stroke, thromboembolic
events, and dementia; women taking estrogen alone had increased risk for stroke, thromboembolic events, and
dementia (less than estrogen/progesterone group); although absolute risk low, both arms of study stopped prematurely because
no evidence of benefit; recommendations—discontinue HRT in women with history of coronary artery event or
stroke; consider stopping 4 to 6 wk before surgery (but data insufficient); note—recent retrospective case-control study
found conflicting results
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| Perioperative medications: women have greater sensitivity to vecuronium, pancuronium, and rocuronium (muscle relaxants),
primarily because of lower volume distribution; dose reduced by 20% to 30%, compared to men; higher sensitivity to opioid
receptor agonists (eg, morphine) results in increased risk for respiratory depression in women (consider reducing dose)
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| Coronary artery bypass grafting (CABG): study showed significantly higher mortality in first 40 days of catheterization
among high-risk women, compared to men with similar risk; risk profile—women undergoing CABG older and more likely
to have diabetes, hypertension, peripheral vascular disease, and depression; women have worse New York Heart Association
(NYHA) functional class, but better left ventricular function; angina more common; morbidity and mortality—although
women have higher rate of mortality during first 30 days after surgery, long-term survival equivalent to or better than men;
women more likely to have perioperative MI and congestive heart failure (CHF) requiring inotropic support; among patients
<50 yr of age, mortality rate of women almost 3-fold that of men; risk for postoperative neurologic events possibly increased
in women; recovery—women have increased requirements for transfusion (possibly independent of differences in hematocrit
and body size), prolonged intubation, longer postoperative stay in intensive care unit (ICU), and longer hospitalization
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 | Factors that may influence outcome: women have worse preoperative profile (reasons may include delayed presentation,
more comorbidities, or delayed identification); fewer diagnostic tests performed in women (difference has diminished
over time); smaller body surface area and coronary arteries may affect prognosis; internal mammary artery (IMA)
grafts used less frequently in women because of anatomic limitations; hypertrophied left ventricle possibly less resilient
to intraoperative changes in volume and transient ischemia during CABG
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| Impact of HRT: mortality equivalent to that of men; may provide protective effect (eg, anti-inflammatory) during postoperative
period
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| Carotid endarterectomy (CEA): asymptomatic carotid disease—women appear to have higher rate of recurrence of neurologic
events and higher rate of mortality; some studies suggest greater risk for stroke in immediate postoperative period,
compared to men; symptomatic carotid disease—CEA confers benefit in men if stenosis ≥50%; women benefit only when
stenosis ≥70%; higher short-term mortality in women
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| PATIENT SELECTION, PREPARATION, AND COMPLICATIONS OF BARIATRIC SURGERY —Howard S. Kaufman,
MD, Associate Professor of Surgery and Obstetrics/Gynecology, Keck School of Medicine of the University of Southern
California, Los Angeles
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| Obesity: lifelong, progressive, life-threatening, costly, genetically-related, multifactorial disease of fat storage with medical,
psychologic, social, physical, and economic comorbid-ties; body mass index (BMI)—standardized measurement calculated
as weight (kg)/[height (m)]2 ; recommendations for surgical management begin at BMI of 35 to 40 for patients with severe
comorbidities or >40 in patients without severe comorbidities; BMI of 40 roughly equivalent to 100 lb excess weight;
prevalence—second leading cause of preventable death in United States (may surpass smoking as leading cause); obesity
accounts for almost twice as many deaths annually as 4 leading causes of cancer death combined; comorbidities—
metabolic and inflammatory problems (eg, diabetes, hypertension, dyslipidemia) and problems associated with excess
weight and pressure (eg, osteoarthritis, pelvic floor dysfunction, obstructive sleep apnea); costs—≈10% of health care
budget related to sequelae of obesity
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| Trends: 4-fold increase in number of adults with BMI >40 in United States from 1991 to 2000; currently, ≈23 million adults
qualify for bariatric surgery, based on BMI alone; contributing factors—ease of access to food; cheapest foods have highest
caloric density and least nutritional value; addiction to convenience and sedentary lifestyle; adverse effects of many
medications include weight gain
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| Management: diet, behavior modification, exercise, and medical management important; surgery reserved for patients who
fail aforementioned interventions; number of bariatric procedures performed in United States increased from 20,000 to
≈150,000 over last 15 yr
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| Vertical banded gastroplasty: stomach may remain attached at angle of His; operation purely restrictive (ie, no malabsorption);
fistulization may occur between gastric pouch and excluded stomach, resulting in regain of weight
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| Roux-en-Y gastric bypass: most common procedure performed for morbid obesity in United States; majority done laparoscopically;
restrictive and slightly malabsorptive operation; bypasses proximal portion of gastrointestinal tract; resulting
gastric pouch holds only ≈1 tablespoon; division of proximal jejunum results in malabsorption
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| Laparoscopic adjustable gastric banding: only truly nondestructive, reversible bariatric operation (more commonly performed
in Europe and Australia); procedure approved by Food and Drug Administration, but insurance agencies often do
not cover cost
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| Duodenal switch with sleeve gastrectomy: most aggressive surgical procedure; stomach volume restricted to ≈100 mL; pylorus
remains intact (eliminates problem of dumping); duodenoileostomy shortens small bowel and results in malabsorption;
candidates include patients unable to comply with dietary restrictions required after Roux-en-Y bypass and severely
obese patients with significant comorbidities
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| Malabsorptive procedures: patient’s ability to ingest food less altered, compared to restrictive procedures; some comorbidities
corrected quickly; rapid weight loss; adverse effects include malodorous stool and gas and risk for protein and vitamin
deficiencies; revision surgery required in 4% of patients
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| Comparison of bariatric procedures: meta-analysis looked at surgical outcomes in 20,000 patients; problems—most studies
had follow-up <2 yr; most studies performed at single institution; most data taken from case series rather than randomized
controlled trials; weight reduction—excess body weight reduced by 60% to 65%; duodenal switch resulted in 72% reduction
in excess body weight (sustained for 10 yr in one case series); 30-day mortality rate—0.1% for purely restrictive procedures;
0.5% for gastric bypass; ≈1% for duodenal switch; symptomatic improvement—70% to 85% of diabetes-related
problems cured or improved, resulting in reduction or elimination of medications; 60% to 85% of patients experienced improvement
or resolution of hypertension; obstructive sleep apnea resolved in 70% to 90% of patients, usually within 1 mo
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| Swedish Obese Subjects (SOS) study: patients followed for 10 yr; outcome of surgical treatment compared to controls (specific
management protocols not specified); patients who underwent surgical treatment had significantly higher rate of
weight loss and sustained weight loss over 10 yr; caloric intake significantly decreased, and energy expenditure significantly
increased in surgical group (sustained over 10 yr); improvements in lipid disturbances (with exception of hyper-
cholesterolemia) and in hypertension, diabetes, and hyperuricemia sustained over 10 yr in surgical group
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| Surgical trends: laparoscopic procedures increasingly common, with shortened stays in hospital; laparoscopic Roux-en-Y
gastric bypass performed on outpatient basis in selected patients
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| Perioperative evaluation: standards not established; diverse patient population necessitates individualized evaluation; identification
and treatment of comorbidities important to optimize condition before surgery; preoperative studies may include laboratory
tests, cardiovascular evaluation, and psychologic evaluation (important); laboratory studies may include testing for
Helicobacter pylori (postoperative effect of infection unknown); deep venous thrombosis (DVT)—obesity increases risk for
thromboembolic events; 2.6% of patients develop DVT as complication of bariatric surgery; pulmonary embolism most common
cause of death related to bariatric surgery (occurs in ≈1% of patients); options for prophylaxis include unfractionated heparin,
low molecular weight heparin, and pneumatic compression; intraoperative considerations—positioning may necessitate
bean bags or other means to support patient and reduce pressure; issues related to laparoscopy, venous access, monitoring, airway
integrity, and anesthesia; members of surgical team may need to assist certain aspects of procedure
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| Programmatic investment: bariatric program requires multidisciplinary group, including specialty consults (preoperative
and postoperative); support groups critical (depression common after bariatric surgery); physical and occupational therapy
required; specialized equipment needed in operating room and elsewhere (eg, toilets, wheelchairs, beds, computed
tomography scanners, and fluoroscopy tables that can accommodate obese patients)
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Educational Objectives
| The goal of this activity is to improve perioperative management of women with coronary artery disease (CAD) and patients
undergoing bariatric surgery. After hearing and assimilating this program, the clinician will be better able to:
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| 1. Compare risk factors, presentation, and prognosis of CAD in women and men.
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| 2. Compare outcomes of coronary artery bypass grafting and carotid endarterectomy in women and men.
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| 3. Discuss differences in perioperative management between women and men.
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| 4. Discuss trends in obesity and bariatric surgery in the United States.
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| 5. Compare risks and benefits of bariatric procedures performed in the United States.
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Discussed on This Program
Dobutamine [Dobutrex]
Drospirenone and ethinyl estradiol [Yasmin]
Morphine sulfate (several trade names)
Pancuronium bromide
Raloxifene [Evista]
Rocuronium bromide [Zemuron]
Tamoxifen citrate [Nolvadex]
Vecuronium bromide [Norcuron]
Suggested Reading
Ali MR, et al: Assessment of obesity-related comorbidities: a novel scheme for evaluating bariatric surgical patients. J Am
Coll Surg 202:70, 2006; Anand SS, et al: Differences in the management and prognosis of women and men who suffer from
acute coronary syndromes. J Am Coll Cardiol 46:1845, 2005; Aubrun F, et al: Sex- and age-related differences in morphine
requirements for postoperative pain relief. Anesthesiology 103:156, 2005; Berger JS, et al: Aspirin for the primary prevention
of cardiovascular events in women and men: a sex-specific meta-analysis of randomized controlled trials. JAMA
295:306, 2006; Birkmeyer NJ, et al: Characteristics of hospitals performing bariatric surgery. JAMA 295:282, 2006; DeMaria
EJ, Carmody BJ: Perioperative management of special populations: obesity. Surg Clin North Am 85:1283, 2005; Edwards
FH, et al: Gender-specific practice guidelines for coronary artery bypass surgery: perioperative management. Ann
Thorac Surg 79:2189, 2005; Nguyen NT, et al: Accelerated growth of bariatric surgery with the introduction of minimally
invasive surgery. Arch Surg 140:1198, 2005; Nussmeier NA, et al: Hormone replacement therapy is safe in women undergoing
coronary artery bypass grafting. Tex Heart Inst J 32:507, 2005; Prystowsky JB, et al: Prospective analysis of the incidence
of deep venous thrombosis in bariatric surgery patients. Surgery 138:759, 2005; Samuels PJ: Anesthesia for
adolescent bariatric surgery. Int Anesthesiol Clin 44:17, 2006; Santry HP, et al: The use of multidisciplinary teams to evaluate
bariatric surgery patients: results from a national survey in the USA. Obes Surg 16:59, 2006; Schulz P, et al: Gender differences
in recovery after coronary artery bypass graft surgery. Prog Cardiovasc Nurs 20:58, 2005; Toumpoulis IK, et al:
Assessment of independent predictors for long-term mortality between women and men after coronary artery bypass grafting:
are women different from men? J Thorac Cardiovasc Surg 131:343, 2006; Wu O, et al: Oral contraceptives, hormone replacement
therapy, thrombophilias, and risk of venous thromboembolism: a systematic review. Thromb Haemost 94:17,
2005.
Faculty Disclosure
In adherence to ACCME guidelines, the Audio-Digest Foundation requests all lecturers to disclose any significant financial relationship
with the manufacturer or provider of any commercial product or service discussed. For this issue, the faculty reported
nothing to disclose.
Drs. Peairs and Kaufman were recorded in Marco Island, Florida, at Perioperative Management, sponsored by Johns
Hopkins University School of Medicine, and held March 6-9, 2005. The Audio-Digest Foundation thanks the speakers
and Johns Hopkins University School of Medicine for their cooperation in the production of this program.
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