PB#105: Bariatric Surgery and Pregnancy Flashcards
Prevalence of obesity in pregnancy
10-36%
Prevalence of obesity among all reproductive-aged women; prevalence of obesity among reproductive-aged Mexican-American pts; prevalence of obesity among reproductive-aged Black pts
29%; 36%; 50%
Effects of obesity on fertility (2)
Reduced fertility, less likely to respond to ovulation induction (even w/ high-dose gonadotropins)
Primary mechanism for reduced fertility 2/2 obesity
Oligo-ovulation/anovulation
Maternal pregnancy risks associated w/ obesity (13)
GDM, pre-E, C/S, infectious morbidity, operative morbidity/postop recovery complications, prolonged op times, increased blood loss, VTE, unsuccessful VTOLAC, iatrogenic PTD, need for IOL/AOL, higher doses of oxytocin, longer labor course
Effects of obesity on iatrogenic vs spontaneous PTD
Iatrogenic PTD higher in obese pts, spontaneous PTL/PTD lower in obese pts
Fetal/Neonatal risks associated w/ obesity in pregnancy (5)
Congenital anomalies, growth abnormalities, sAB, IUFD, subsequent childhood obesity
Most common congenital anomalies associated w/ obesity in pregnancy (3)
ONTDs, cardiac anomalies, facial clefting
RR of IUFD in obese pts compared to normal weight pts
2.1–4.3-fold greater
Effect of increasing BMI on OB US
Worsening visualization of congenital anomalies, though no effect on EFW calculations
Nonsurgical weight loss approaches (4)
Behavioral changes, diet, exercise, pharmacotherapy
Candidates for bariatric surgery
Pts w/ BMI >40, or pts w/ BMI >35 and other comorbidities
Most effective therapy for morbid obesity
Bariatric surgery
Two general approaches to bariatric surgery
Restrictive, restrictive-malabsorptive combo
Two common bariatric surgeries currently in use, and classification of each one
Roux-en-Y (restrictive-malabsorptive combo), adjustable gastric banding (restrictive)
Pathophysiology of Roux-en-Y procedure
Creates a roux (straight) limb connected to gastric pouch and Y-portion downstream as enteroenterostomy, w/ proximal stomach separate from remaining part of stomach w/ staples
Pathophysiology of gastric banding
Fluid-filled band is placed around stomach near fundus, reducing functional stomach volume
Surgically route of roux-en-Y and of gastric banding
Both can be performed laparoscopically or open
Less common bariatric procedures, and classification of each one (2)
Vertical banded gastroplasty (restrictive), biliopancreatic diversion (malabsorptive)
Effects of weight loss following bariatric surgery on fertility (4)
Improvement in PCOS, improvement in anovulation, improvement in irregular menses, improvement in fertility rates
Risk associated w/ contraception following malabsorptive surgery
Possibility of decreased absorption of OCPs
Most effective intervention to improve medical comorbidities associated w/ obesity (outside of pregnancy)
Weight loss
Percentage of pregnant pts that are still obese after bariatric surgery
80%
Pregnancy risks associated w/ hx of bariatric surgery (3)
Hx of C/S, GDM, need for C/S
Does bariatric surgery improve C/S rates in obese pts?
No (they are comparable in pts s/p bariatric surgery compared to obese pts prior to surgery, and as high as 62%)
Pregnancy conditions that are less likely following bariatric surgery (4)
HTN, pre-GDM, weight gain during pregnancy, fetal macrosomia
Possible late complications in pregnancy following prior bariatric surgery (3)
Intestinal obstruction, GI hemorrhage, maternal death
Does bariatric surgery improve rates of congenital anomalies in future pregnancies?
Yes (rate of congenital anomalies in pts s/p bariatric surgery is comparable to general population)
Is maternal weight gain during pregnancy a predictor of birth weight in pts s/p bariatric surgery?
Yes
Is bariatric surgery associated w/ increased risk of perinatal death?
No
Pregnancy rates in adolescent pts s/p bariatric surgery
Doubled (12.8% vs 6.4%)
Contraceptive considerations for adolescent pts s/p malabsorptive bariatric surgery
Non-PO administration methods (2/2 higher risk of OCP failure)
Recommended delay in pregnancy s/p bariatric surgery; reasons why (2)
12-24 months; to avoid fetal exposure to rapid maternal weight loss, to help achieve complete weight loss goals
Considerations if pregnancy occurs within 12-24 month window s/p bariatric surgery (2)
Close surveillance of maternal weight/nutritional status, additional fetal monitoring (if needed)
Most common nutritional deficiencies after roux-en-Y (6)
Protein, iron, vit B12, folate, vit D, calcium
When to evaluate for micronutrient deficiencies for pregnant pts s/p bariatric surgery
At FOBV
Labs to check qtri in pregnant pts s/p bariatric surgery in absence of specific nutritional deficiency (5)
CBC, iron, ferritin, calcium, vit D
Route of methods to correct nutritional deficiencies
Can be started PO, but parenteral forms may be indicated if no improvement
Percentage of pts s/p bariatric surgery who continue to take the prescribed multivitamin supplement long-term
14-59%
Daily recommended protein intake (regardless of bariatric surgery status)
60g
In what situations is caloric/protein restriction recommended for pregnant pts s/p bariatric surgery?
Never (even if they continue to be obese/overweight)
Should pregnant pts s/p bariatric surgery take a PNV, a bariatric multivitamin, or both?
Both
PP considerations in pts s/p bariatric surgery
Close infant surveillance 2/2 risk for nutritional deficiencies when breastfed
Can nutritional deficiencies occur after restrictive bariatric surgery; why/why not?
Yes; 2/2 decreased food intake and/or intolerance to certain foods because of narrowed gastric opening
Consideration in pregnancy for pts who have gastric banding
Active band management (fluid from gastric band is removed/lessened)
Benefits of active band management in pregnancy (3)
Allows for less gastric constriction, increased PO intake, decreased 1st tri N/V sxs
Which consultant is recommended early in pregnancy for pts s/p bariatric surgery?
Bariatric surgeon
Potential complications s/p bariatric surgery (6)
Anastomotic leaks, bowel obstructions, internal hernias, ventral hernias, band erosion, band migration
Management of N/V, abdominal pain in pregnant pts s/p bariatric surgery
Broad workup (do not presume to be pregnancy-related)
Syndrome that may occur s/p gastric bypass; pathophysiology of this condition
Dumping syndrome; ingestion of refined sugars/high glycemic carbs is followed by rapid emptying from stomach into small intestine, and fluid shifts from intravascular compartment into bowel lumen resulting in small bowel distention
Sxs of dumping syndrome (4)
Cramping, bloating, N/V, diarrhea
Downstream physiologic changes associated w/ dumping syndrome (2); sxs associated w/ downstream effects of dumping syndrome (4)
Hyperinsulinemia, hypoglycemia; tachycardia, palpitations, anxiety, diaphoresis
Evaluation option for GDM for pts s/p bariatric surgery in order to avoid dumping syndrome
Fasting + 2h PP glucose logs x1 week (since may not tolerate 1*GTT) at 24-28wga
Effect of malabsorptive bariatric surgery on med absorption
Absorptive surface of intestine is decreased, so decreased time for med absorption
Med preparations to avoid in pts s/p malabsorptive bariatric surgery; preferred med preparations in pts s/p malabsorptive bariatric surgery (2)
ER formulations; PO solution, IR formulations
Class of meds to avoid in PP pts who have had bariatric surgery; why?
NSAIDs; 2/2 smaller gastric pouch
Considerations for pts who have had bariatric surgery who are taking meds that necessitate therapeutic drug level
More frequent/regular drug level testing
Does uncomplicated hx of bariatric surgery alter labor management, route of delivery, or need for C/S?
No
Prelabor consultation for pts w/ extensive/complicated abdominal surgery related to weight loss procedures
Bariatric surgeon
