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Bariatric surgery: Postoperative and long-term management of the uncomplicated patient

Bariatric surgery: Postoperative and long-term management of the uncomplicated patient
Author:
Giselle Hamad, MD
Section Editor:
Daniel Jones, MD
Deputy Editor:
Wenliang Chen, MD, PhD
Literature review current through: Dec 2022. | This topic last updated: May 04, 2021.

INTRODUCTION — Obesity, a chronic illness identified in children, adolescents, and adults, has reached epidemic proportions worldwide [1-4]. In the United States alone, 42.4 percent of adults and 19.3 percent of children and adolescents were obese in 2017 to 2018 [4-7]. The rate of obesity has more than tripled since 1991 [8,9]. Worldwide, the rate of obesity has tripled between 1975 and 2016; more than 39 percent of adults and more than 18 percent of children in the world are obese or overweight [10].

Bariatric surgery, a commonly performed procedure in the United States [11], remains the most effective method of weight loss and can result in partial or complete resolution of multiple obesity-related comorbidities, including type 2 diabetes mellitus, hypertension, hypercholesterolemia, and obstructive sleep apnea [12].

The immediate postoperative care for the uncomplicated postsurgical patient and outpatient management of all bariatric surgical patients will be discussed in this topic. The indications and types of bariatric procedures, complications, management of complicated postoperative patients (eg, multiple or refractory comorbidities) in the intensive care unit, and outcomes are reviewed separately:

(See "Bariatric procedures for the management of severe obesity: Descriptions".)

(See "Bariatric operations: Early (fewer than 30 days) morbidity and mortality".)

(See "Intensive care unit management of patients with obesity".)

(See "Outcomes of bariatric surgery".)

IN-HOSPITAL POSTOPERATIVE CARE — Patients with an uncomplicated preoperative and intraoperative course are typically transferred from the operating room to the post-anesthesia unit and subsequently to the inpatient surgical floor. Continuous cardiac and oxygen saturation monitoring for 24 to 48 hours is recommended for patients with a history of cardiac arrhythmias or coronary artery disease and/or chronic obstructive pulmonary disease (COPD), sleep apnea, and/or asthma.

Surgical intensive care unit (SICU) monitoring is rarely necessary following a bariatric operation unless the patient has complicated or refractory comorbid illnesses or the operation was complicated with a large amount of blood loss, cardiac instability, or the need for prolonged intubation. (See "Intensive care unit management of patients with obesity".)

Post-anesthesia care unit — Most stable patients undergoing a bariatric operation, including those patients without complicated preoperative comorbidities, are admitted to the post-anesthesia care unit (PACU) immediately at the conclusion of the operation. PACU management is reviewed separately. (See "Anesthesia for the patient with obesity", section on 'Post-anesthesia care unit management'.)

Surgical floor inpatient management — After anesthetic and surgical management in the PACU is completed, most patients are transferred to the inpatient surgical postoperative unit. For the next 24 hours, the postoperative priorities include control of pain, nausea and/or vomiting, intravenous fluid management, pulmonary hygiene, and ambulation. Pain is controlled with oral oxycodone. Incentive spirometry is encouraged to reduce atelectasis. Oxygen is administered by nasal cannula in the PACU and weaned thereafter. Patients with obstructive sleep apnea are managed with continuous positive airway pressure (CPAP) [13].

Patients receive intravenous fluids and are allowed sips of water and ice chips on the night of surgery. Urine output is monitored overnight. Ambulation is encouraged beginning on the night of surgery. Antiemetics such as ondansetron are given as needed. On postoperative day (POD) 1, a basic metabolic profile (eg, electrolytes, renal function blood tests) and a complete blood count are obtained. (See "Management of acute perioperative pain in adults".)

Radiographic studies — Routine use of upper gastrointestinal (UGI) series to rule out anastomotic or staple line leak has been shown to be low yield [14,15] and increases length of hospital stay [16]. Furthermore, there is evidence that the vast majority of staple line leaks after a sleeve gastrectomy (SG) are not diagnosed on routine postoperative UGI series; instead, they present clinically in 10 to 14 days after the patient has already been discharged [17,18].

Postoperative imaging studies and early complications following bariatric operations are reviewed elsewhere. (See "Imaging studies after bariatric surgery" and "Bariatric operations: Early (fewer than 30 days) morbidity and mortality".)

Reoperation — For patients who have an anastomotic leak or obstruction identified in the early postoperative period, an immediate return to the operating room for an exploration and revision is warranted.

Respiratory distress – Subtle indications of respiratory distress in the first few hours to days after bariatric surgery may reflect the respiratory compensation to lactic acidosis induced by substantial tissue hypoperfusion; this may be an early sign of an impending abdominal catastrophe [19].

Sustained tachycardia – For patients who have undergone a Roux-en-Y gastric bypass (RYGB) or an SG and who develop sustained tachycardia of greater than 120 beats per minute without a cardiac event, an anastomotic leak must be suspected [20]. There should be no delay in exploring these patients; a negative exploration is preferable to an undiagnosed leak and the potential for disastrous sequelae. One should not dismiss tachycardia; a leak may be present despite the absence of fever, leukocytosis, abdominal pain, or abdominal tenderness.

Persistent vomiting Persistent vomiting in the early postoperative period after RYGB is not routine. If there is bilious vomiting or dilated small bowel on radiographic studies (eg, abdominal films), a technical complication causing an obstruction is highly likely, and the patient should be re-explored promptly [21,22]. (See "Bariatric operations: Early (fewer than 30 days) morbidity and mortality".)

Venous thromboembolism — Most bariatric surgery patients are considered high risk for venous thromboembolism (VTE) given the prevalence of risk factors that promote VTE, including obesity, obstructive sleep apnea/hypoventilation syndrome, and exposure to general anesthesia.

Nevertheless, there is considerable variability among bariatric surgeons in the approach to thromboprophylaxis because of a lack of consensus regarding the optimal thromboprophylaxis strategy for this population [23,24]. The current American Society of Bariatric and Metabolic Surgeons (ASMBS) guidelines regarding VTE prophylaxis state that all bariatric patients receive mechanical prophylaxis and are recommended to ambulate early in the postoperative period. Additionally, the surgeon may routinely utilize chemical prophylaxis consisting of either low-molecular-weight heparin [25] or unfractionated heparin [26]. (See "Intensive care unit management of patients with obesity", section on 'Anticoagulants'.)

Patients who are considered at a higher level of risk for VTE, such as patients with hypercoagulable disorders, history of previous VTE, or body mass index greater than 60 kg/m2, may be considered for extended administration of VTE prophylaxis [27]; there is no consensus regarding indications for extended prophylaxis for patients undergoing bariatric surgery [28-30].

Prevention of postoperative VTE is reviewed in detail separately. (See "Prevention of venous thromboembolic disease in adult nonorthopedic surgical patients".)

Diabetes mellitus — For patients with diabetes, serum glucose is monitored every six hours during the hospital admission with a goal of maintaining glucose levels between 140 and 180 mg/dL [31]. Close glucose monitoring is necessary after discharge, especially following RYGB, because of the risk of developing hypoglycemia after RYGB [32]. Preoperative classes are generally offered in bariatric centers to familiarize patients with a glucometer and insulin administration. Signs, symptoms, and treatment of hypoglycemia and hyperglycemia are discussed. The protocols for managing diabetes after bariatric surgery vary between centers. (See "Overview of general medical care in nonpregnant adults with diabetes mellitus" and "Outcomes of bariatric surgery", section on 'Diabetes mellitus'.)

POSTOPERATIVE CARE AFTER DISCHARGE — Patients undergoing laparoscopic Roux-en-Y gastric bypass (RYGB) or sleeve gastrectomy (SG) are discharged on postoperative day 1 or 2, providing they are tolerating a clear liquid diet. The rare patients who have an open procedure remain hospitalized for a day or two longer or until they are able to tolerate a liquid diet and ambulate.

Hydration — Patients must be educated preoperatively so that they know what to expect postoperatively, and this includes hydration. Fluid intake after discharge should be emphasized because of the vicious cycle of dehydration and nausea that often results in emergency room visits for dehydration.

Nutrition and supplementation — Within the first 14 days after bariatric surgery, vitamin and mineral supplementation consists of a daily multivitamin for all patients [33]. Additional vitamin supplementation can be offered to RYGB and SG patients at the discretion of bariatric surgeons [34,35]. (See "Bariatric surgery: Postoperative nutritional management", section on 'Micronutrient deficiency, supplementation, and repletion'.)

In our practice, we recommend additional routine supplementation for RYGB patients with oral vitamin B12 500 micrograms daily, vitamin C 500 mg daily (taken with iron), calcium carbonate or citrate 500 mg twice a day, and ferrous sulfate 325 mg daily [36-38]. Calcium and iron supplementation should not be administered simultaneously.

SG patients should receive a multivitamin, vitamin B12, and iron supplementation [39]. Both RYGB and SG patients are at risk of vitamin D deficiency and require routine supplementation with vitamin D3 2000 international units daily [40,41].

Diet — The dietary regimen depends upon the type of bariatric procedure performed. All patients are advised to avoid concentrated sweets and to avoid carbonation and straws when drinking liquids to minimize gastric bloating. (See "Bariatric surgery: Postoperative nutritional management", section on 'Diet and texture progression'.)

For patients undergoing an RYGB or SG procedure, they are instructed to limit oral intake to clear liquids for the first two weeks after discharge. They should consume 64 ounces (1.89 liters) of clear liquids daily since dehydration is a common reason for readmission. Patients are then advised to consume a pureed diet or full liquids for the next two weeks, then a soft diet for two months. At the third postoperative month, the patients are advanced to a regular diet.

Vitamin K — For those patients requiring warfarin, close monitoring of prothrombin time and international normalized ratio (INR) is required when restarting warfarin postoperatively because of the tendency for these patients to become coagulopathic. This may be secondary to altered pharmacokinetics or pharmacodynamics, medication interactions, or an alteration in the absorption, intake, or storage of vitamin K [42]. Prothrombin time and INR should be obtained daily until the values stabilize.

The interaction of vitamin K and warfarin and the management of warfarin as an outpatient are reviewed separately:

(See "Overview of vitamin K".)

(See "Warfarin and other VKAs: Dosing and adverse effects".)

(See "Management of warfarin-associated bleeding or supratherapeutic INR".)

(See "Biology of warfarin and modulators of INR control".)

Activity restrictions — Patients must refrain from working for one to two weeks following an LAGB operation and for two to four weeks following an RYGB and SG operation. Patients may shower but are instructed not to soak in a bathtub. They are also advised to avoid heavy housework and may not lift more than 10 pounds.

Medications — Patients are sent home with oxycodone along with oral acetaminophen to reduce opiate utilization. Patients are advised not to drive a motor vehicle or operate heavy machinery while taking pain medication. RYGB patients must not take ibuprofen, naproxen, or other anti-inflammatory medications because of the risk of gastrojejunal ulcer development [43]. They are not permitted to take aspirin unless they have a vascular or coronary stent or a prior cerebrovascular accident. Those who need to take aspirin or prednisone for medical conditions should also take a proton pump inhibitor to prevent marginal ulcers [44]. RYGB patients should crush tablets or take liquid medications. They may not crush extended-release medications or open capsules [45].

Certain bariatric procedures may affect the absorption of direct oral anticoagulants (DOACs) for patients who take them (table 1).

Warning signs of potential complications — Patients should notify their surgeon for a temperature greater than 100.5°F (38.1°C), severe abdominal pain, redness around the incisions, drainage from the incisions, vomiting, chest pain, shortness of breath, or severe pain, warmth, or redness in the calf.

Follow-up schedule — Follow-up schedules vary among bariatric surgeons. In the absence of postoperative complications, patients who had an RYGB or SG are typically scheduled for routine office visits at two and four weeks following discharge; then at 3, 6, and 12 months; then annually.

LONG-TERM MANAGEMENT — Bariatric surgical patients require lifelong follow-up visits. Ongoing monitoring of body weight and compliance with the postsurgical regimen is necessary for long-term success and micronutrient deficiency detection [36,46,47].

Long-term, all patients are encouraged to drink water and to avoid carbonation and straws, which promote gastric bloating. Caffeinated beverages should be avoided because of the diuretic effect [48]. Processed snack foods and sweetened beverages are discouraged because they carry little nutritional value and increase calorie intake.

Consumption of lean protein sources is encouraged. The need for vitamin and mineral supplementation should be reinforced at every visit to avoid micronutrient deficiencies [49]. Routine exercise should be encouraged [50,51]; walking is an appropriate way to start exercising. Patients with degenerative joint disease may benefit from aquatic exercise to reduce joint pain.

Multidisciplinary team — Nurses and advanced practice providers assist the bariatric surgeon in addressing postoperative questions and concerns and can triage a patient who presents with a potential complication. A registered dietitian can optimize results by reinforcing the bariatric dietary regimen [52]. Free monthly support groups are offered and are attended by both preoperative and postoperative bariatric surgery patients. Our team also offers cooking classes, exercise classes, and behavioral therapy. (See "Bariatric surgery for management of obesity: Indications and preoperative preparation", section on 'Preoperative assessment'.)

Assessment and management of changes in comorbid diseases — Comorbidity status is routinely assessed at every postoperative visit, including hypertension, diabetes, metabolic deficiencies, hyperlipidemias, and sleep apnea. However, there is variability in the frequency and type of testing ordered among bariatric surgeons. Medication changes are typically managed by the primary care clinician or specialist (eg, cardiologist, endocrinologist).

Medical outcomes after a bariatric operation are reviewed elsewhere (see "Outcomes of bariatric surgery", section on 'Metabolic effects'):

Hypertension has been closely linked to obesity. Blood pressure is routinely measured at every postoperative visit to monitor response to the operation, and antihypertensive medications are reviewed. (See "Overweight, obesity, and weight reduction in hypertension".)

Diabetes is effectively treated by bariatric surgery, and the need for insulin and/or oral hyperglycemics should be evaluated on each visit in the early postoperative time frame. HgA1C is followed to monitor diabetes severity, and changes in diabetic medications are reviewed. (See "Bariatric surgery: Postoperative nutritional management" and "Management of persistent hyperglycemia in type 2 diabetes mellitus".)

Metabolic deficiencies can be created by Roux-en-Y gastric bypass (RYGB) and are monitored by laboratory evaluations that include serum calcium, iron, vitamin B12, vitamin D, folate, and thiamine every six months for the first two years, then annually. (See "Bariatric surgery: Postoperative nutritional management", section on 'Micronutrient management'.)

Hyperlipidemia is monitored by evaluation of serum lipids and cholesterol and any medication adjusted accordingly. (See "Management of low density lipoprotein cholesterol (LDL-C) in the secondary prevention of cardiovascular disease".)

Sleep apnea may be reassessed with a sleep study in 6 to 12 months after surgery to reassess the continuous positive airway pressure (CPAP) requirement. (See "Management of obstructive sleep apnea in adults" and "Clinical presentation and diagnosis of obstructive sleep apnea in adults".)

Gastroesophageal reflux is common among SG patients [53]. (See "Medical management of gastroesophageal reflux disease in adults" and "Complications of gastroesophageal reflux in adults" and "Surgical management of gastroesophageal reflux in adults".)

Additional comorbid illnesses that may develop long-term (more than 30 days) following bariatric surgery are described in a separate topic and include (see "Late complications of bariatric surgical operations"):

Dumping syndrome is assessed for patients who have undergone an RYGB procedure, which is particularly evident after patients consume sweet foods [54]. This may result in tachycardia, abdominal pain, diaphoresis, nausea, vomiting, diarrhea, and, later, hypoglycemia [55]. These patients should be counseled to take dietary measures to avoid the triggering food or drink. (See "Evaluation of postprandial symptoms of hypoglycemia in adults without diabetes", section on 'Alimentary hypoglycemia'.)

Marginal, or gastrojejunal, ulcers occur in up to 25 percent of RYGB patients and typically present with epigastric pain and nausea. Risk factors include tobacco, aspirin, and nonsteroidal anti-inflammatory medications (NSAIDs) [43,56]. Treatment consists of proton pump inhibitors, sucralfate, and discontinuation of the offending agents. If severe, marginal ulcers may be complicated by gastrointestinal (GI) bleeding or perforation. Prophylactic protein pump inhibitors have been advocated for ulcer prevention [44,57]. (See "Imaging studies after bariatric surgery" and "Postgastrectomy complications".)

Cholelithiasis is a common cause of upper abdominal pain after bariatric surgery because of a change in bile composition [58]. In addition, rapid weight loss promotes gallstone formation [59,60]. Patients who still have their gallbladders are started on ursodeoxycholic acid (ursodiol) 300 mg orally twice a day for six months to prevent gallstone formation [59]. (See "Choledocholithiasis: Clinical manifestations, diagnosis, and management".)

Nephrolithiasis is identified in approximately 8 percent of RYGB patients [61]. RYGB patients are prone to an increase in oxaluria that can promote kidney stones and can progress to oxalate nephropathy and renal failure [62,63]. Therefore, patients should be counseled to avoid dietary oxalate. (See "Kidney stones in adults: Diagnosis and acute management of suspected nephrolithiasis" and "Kidney stones in adults: Surgical management of kidney and ureteral stones".)

Depression may be a preoperative comorbid illness or present as a postoperative manifestation. The bioavailability of serotonin reuptake inhibitor antidepressant medications is reduced after RYGB [64]; therefore, patients with mental illness may be at risk for exacerbation of depressive symptoms and should be monitored closely after RYGB. (See "Screening for depression in adults" and "Unipolar depression in adults: Assessment and diagnosis".)

Stenosis following a sleeve gastrectomy (SG) can lead to gastric outlet obstruction and present as dysphagia or vomiting [65]. This is diagnosed by an upper gastrointestinal study and may be managed with endoscopic dilation. Surgical revision may be required if endoscopic management fails [66]. (See "Imaging studies after bariatric surgery" and "Gastrointestinal endoscopy in patients who have undergone bariatric surgery".)

Unexplained abdominal pain can occur in any patient after an intra-abdominal operation. For patients who have had an RYGB procedure and present with unexplained abdominal pain, there should be a low threshold for offering surgical exploration, which may be approached laparoscopically, to identify an occult internal hernia, intussusception, or small bowel obstruction, even if physical examination is impressive and imaging studies are unrevealing. (See "Imaging studies after bariatric surgery" and "Evaluation of the adult with abdominal pain" and "Causes of abdominal pain in adults".)

Improvements in physical function — Bariatric surgery results in complete or partial resolution of multiple medical comorbidities as well as an improvement in quality of life [67-69]. Weight loss allows patients to increase their physical activity [70], which in turn promotes greater weight loss, cardiorespiratory fitness, and quality of life [71]. Exercise regimens are discussed, and patients are encouraged to incorporate both cardiovascular exercise and resistance training on a regular basis. Patients may elect to undergo body contouring surgery when their weight is stable to address hanging skin on the abdomen, buttocks, breasts, arms, and legs.

SOCIETY GUIDELINE LINKS — Links to society and government-sponsored guidelines from selected countries and regions around the world are provided separately. (See "Society guideline links: Bariatric surgery".)

SUMMARY AND RECOMMENDATIONS

For the first 24 hours after the bariatric operation, the postoperative priorities include control of pain, nausea and/or vomiting, intravenous fluid management, pulmonary hygiene, and ambulation. (See 'Surgical floor inpatient management' above.)

For patients who have an anastomotic leak or obstruction identified in the early postoperative period, an immediate return to the operating room for an exploration and revision is warranted. Sustained tachycardia over 120 beats per minute may be the presenting symptom of an intra-abdominal adverse event. (See 'Reoperation' above.)

Patient management after surgery includes an assessment of hydration and medical comorbid illnesses, such as hypertension, diabetes, and sleep apnea. (See 'Postoperative care after discharge' above.)

For long-term success and early identification of complications, lifelong follow-up is recommended after bariatric surgery. (See 'Long-term management' above.)

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Topic 88610 Version 15.0

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