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Octavia Pickett-Blakely, M.D. and Mimi Huizinga, M.D.
02-24-2011
Trinidad and Tobago Information Author: Dilip Dan, M.D.
- Of the bariatric surgeries performed annually in Trinidad and Tobago, 25% are in persons with diabetes. (Dan, unpublished).
- As of early 2010, 128 Roux-en-Y Gastric bypasses, 8 gastric bands and 2 sleeve gastrectomies have been performed in Trinidad. All but 1 done laparoscopically. No mortality complications reported. (unpublished)
- Surgeries are performed predominantly in the private practice as they are not offered in the public sector.
- Few insurance carriers do provide limited coverage for the procedures but, unfortunately, many see bariatric surgery as cosmetic.
- All resources are currently available in Trinidad to support this patient population both during and after surgery (i.e. surgeon, endocrinologist, cardiologist, psychologist, general hospital services and other patient support).
- Mortality generally <1% and related to a pulmonary embolus or anastamotic leak in the majority of patients.
- Mechanisms for resolution of diabetes include weight loss related to restriction and /or malabsorption; also, but diabetes sometimes resolves within a few days of surgery long before any significant weight loss has occurred.
- The foregut theory suggests that exclusion of a short segment of proximal small intestine has a direct antidiabetic effect.
- The hindgut theory suggests that after a gastric bypass, expedited delivery of nutrients to the lower intestine increases the secretion of GLP-1 and improves diabetic control.
- Weight regain can occur with all forms of bariatric surgery. Patients with a gastric bypass have >70% success and band or sleeve gastrectomy patients >50% at 10 years.
- Careful pre-operative optimization is essential. Higher BMI and associated co-morbidity are directly related to morbidity.
- Plastic surgery is reserved for 2 years following bariatric surgery. Pregnancy should also be delayed for 2 pears post-operatively. Fertility improves following surgery.
- Future treatment of newly-diagnosed diabetes (in the obese or non-obese) may include some form of bariatric surgery (altered for the non-obese) called 'Metabolic Surgery' and it is gaining rapid attention in numerous trials.
- A frequently done, effective surgical intervention for morbidly obese individuals to reduce weight and improve obesity-related comorbidities such as diabetes. Results in weight loss by restriction of overall nutrient intake, malabsorption of nutrients, and/or a combination of restriction and malabsorption.
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Laparoscopic adjustable gastric band: restrictive procedure that inserts a band around the proximal stomach; the band is connected to a subcutaneous port used to adjust the amount of gastric restriction provided by the band.
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Laparoscopic sleeve gastrectomy: restrictive procedure that removes large portion of the greater curvature of the stomach leaving a stomach "sleeve" along the lesser curvature. Can be done as the first part of a duodenal switch or as a stand alone procedure.
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Roux-en-Y gastric bypass: combination restrictive and malabsorptive procedure that creates a small gastric pouch by separating the proximal and distal stomach; the proximal gastric pouch is anastamosed to a loop of jejunum ("Roux limb"), while the bypassed distal stomach and proximal small bowel ("Y limb") is anastamosed distally to the jejunum.
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Biliopancreatic diversion (BPD) with or without duodenal switch: combination restrictive and malabsorptive procedure that creates a laparoscopic sleeve gastrectomy with remaining stomach either: 1) attached to lower portion of smaller intenstine (BPD) or 2) attached to upper small intestine with creation of separate biliary loop, both of which connect to common channel of lower smaller intestine (duodenal switch).
- Up to 55% of all patients diagnosed with diabetes are obese (CDC).
- Of an estimated 225,000 bariatric surgeries performed per annum, 15- 30% have diabetes (CDC).
- Bariatric surgery can result in the resolution of type 2 diabetes in 48-98% of cases depending on the type of surgery performed (Segal,Vetter).
- Diabetes-related mortality and all- cause mortality is significantly decreased after gastric bypass (Christou,Segal).
- Eligibility for bariatric surgery is established according to National Institutes of Health guidelines: BMI > 40 kg/m2 or a BMI > 35 kg/m2 with an obesity- related comorbidity such as diabetes, hypertension, obstructive sleep apnea, obesity hypoventilation syndrome, pickwickian syndrome, severe urinary incontinence, hyperlipidemia, debilitating osteoarthritis, nonalcoholic fatty liver disease, coronary artery disease, gastroesophageal reflux disease, and pseudotumor cerebri (NIH consensus conference).
- In February 2011, FDA approved use of laparoscopic adjustable gastric banding for BMI >30 kg/m2 with an obesity-related comorbidity in response to a study presented by the manufacturer that showed significant weight loss after the surgery for persons who were mildly obese.
- Specific coverage guidelines vary by insurance carrier (e.g. documentation of a failed trial of diet and exercise and performance of surgery at an American Society for Bariatric Surgery designated Center of Excellence).
- Insulin requiring patients often require significantly lower doses of insulin and oral hypoglycemic agents post-operatively due to decreased oral intake.
- With Roux-en-Y or BPD procedures, hyperglycemia may improve dramatically within several days, well before significant weight loss.
- Advance oral intake according to institution or provider specific protocols. Most diets begin with clear liquids and advance to full liquids or pureed foods that are high in protein and low in fat and carbohydrates.
- A combination of basal and rapid- acting prandial insulin is preferred to keep fasting blood glucose levels between 80 and 110 mg/dl and post-prandial glucose levels below 180 mg/dl.
- Some patients only require meal-time insulin during this time period due to irregular intake and decreasing insulin requirements.
- Doses of oral agents should be withheld or adjusted in non-insulin requiring patients. Specifically, secretagogues should be discontinued in the immediate post-operative period.
- Oral intake is advanced further from full liquids and pureed foods ultimately to a regular diet (small, frequent meals) consisting of high protein, low fat and low carbohydrate meals.
- In patients with Type 2 diabetes, home preprandial and fasting blood glucose measurements should be performed periodically.
- The use of insulin and/or oral agents is dictated by the patient's home glucose measurements and often declines within 1 year of bariatric surgery (in up to 76%).
- Most patients will be off insulin and oral agents by 3 months post-operatively.
- Post-bariatric surgery patients are at risk for a variety of micronutrient deficiencies including: B12, iron, calcium, vitamin D, folate, B1 and others.
- All patients receiving bariatric surgery should be started on a multivitamin with iron and calcium citrate with vitamin D after bariatric surgery.
- Patients should be monitored regularly for micronutrient deficiencies. The frequency depends on the type of surgery. Patients undergoing laparoscopic adjustable band should be monitored annually, gastric bypass require monitoring every 3-6 months, and bilopancreatic diversion patients should be monitored every 3-6 months.
- Although calcium is absorbed throughout the small intestine and colon, calcium containing foods (e.g. milk, cheese) may provoke bloating, cramping and diarrhea in a post-bariatric patients placing them at risk for deficiency. Calcium citrate with vitamin D is the recommended form of calcium because of increased absorption.
- Oral B12 is often not sufficient to replete B12 deficiencies. B12 should be administered in sublingual, intranasal or intramuscular forms given that oral B12 is not absorbed due the anatomical disruption of B12 and intrinsic factor binding in gastric bypass and other malabsorptive surgeries (biliopancreatic diversion/duodenal switch).
- Iron absorption is impaired in gastric bypass and other malabsorptive surgeries due to bypass of the duodenum (the site of iron absorption). Some patients may require intravenous iron therapy.
- Folate deficiency may occur as a result of B12 deficiency, impaired intestinal absorption, or inadequate oral intake. Folate supplementation is recommended in patients after bariatric surgery.
- B1 deficiency can arise in the setting of inadequate oral intake, or impaired intestinal absorption, and may result in Wernicke-Korsakoff syndrome. B1 is usually a component of most multivitamin preparations, but deficient individuals can be treated with intramuscular injections.
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Vitamin D deficiency can result from decreased oral intake, and impaired absorption due to poor mixing of vitamin D with bile salts. Daily oral supplementation is recommended.
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Medical: Electrolyte abnormalities
- Dumping syndrome (hyperinsulinemic hypoglycemia approximately 30 minutes post prandially resulting from rapid gastric emptying). Dumping syndrome less in BPD with duodenal switch.
- Nesidioblastosis (hyperinsulemic hypoglycemia greater than 1 hour post prandially resulting from pancreatic beta cell hyperfunction) remains controversial (Service).
- Weight regain
- Gallstones
- Loose skin after weight loss
- Laparoscopic adjustable band: vomiting, pain, dysphagia, reflux
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Surgical: Roux-en-Y gastric bypass or BPD: anastamotic leak, marginal ulceration, stomal stenosis
- Laparoscopic adjustable band or sleeve gastrectomy: band malfunction (slippage, erosion, infection), leakage, hemorrhage, fistula.
- Follow-up in bariatric surgery patients depends on the comorbidities and the type of surgery performed. Note, above, potential complications.
- Diabetes recurrence can be as high as 43% after Roux-en-Y gastric bypass (associated with lower pre-operative BMI, failed weight loss, weight regain, and high post-operative blood glucose) (Vetter).
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Hemoglobin A1c monitoring should be continued in the post-operative period.
- Weight loss depends on the type of operation performed. Expected average weight loss in the first 1-2 years after surgery is 45-85% and 29-87% for Roux-en-Y gastric bypass and laparoscopic adjustable band surgery, respectively (Buchwald).
- There is often a significant decline in post-operative requirements for insulin or oral agents due to improved insulin sensitivity post-operatively. Glucose tolerance may normalize.
- Maintain a high index of suspicion for micronutrient deficiencies.
- Bariatric surgery is covered by many insurance carriers (e.g. Medicaid) but specific coverage guidelines are carrier dependent.
- Bariatric surgery enforces a new relationship to food: patients cannot eat the amount of food they previously consumed.
- Recent findings include an increased incidence of post-operative, long-term hyperinsulinemic hypoglycemia associated with pancreatic beta cell hyperplasia (nesidioblastosis); however, these findings remain controversial.
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