Complications after Bariatric Surgery

Bariatric Surgery Complication

Anand Swaminathan MD and Arvind Venkat MD

Print editor: Whitney Johnson MD MS

Take Home Points

• Laparoscopic sleeve gastrectomies are performed more commonly than Roux-en-Y bypass.
• Procedures that surgically change the anatomy of the GI tract are at risk for operative complications such as anastomotic leaks, breakdown of suture lines, hernias and obstructions.
• Consider alternative diagnoses such as pulmonary embolism.
• Lap-band procedures may migrate and this is best evaluated with Gastrografin upper GI series.
• Bariatric surgeries may lead to severe vitamin deficiencies such as Wernicke-Korsakoff syndrome.

• We are seeing more patients in the emergency department after bariatric surgery. In April 2017, we discussed a case of acute abdominal pain after bariatric surgery, but it has been some time since we have done an in-depth discussion of bariatric emergencies.
• Bariatric surgery encompasses a variety of procedures.
  • The number of bariatric operations in the United States has increased from 158,000 in 2011 to 228,000 in 2017.
  • The two main approaches are to restrict dietary intake or to bypass part of the gut to avoid caloric absorption.
  • Previously, the most common procedure was the Roux-en-Y gastric bypass but this is no longer the case. The most common procedure now is the laparoscopic sleeve gastrectomy which involves removal of a section of the stomach to decrease stomach size and change gut hormones. This comprises about 60% of procedures currently. Roux-en-Y bypass now makes up about 18% of procedures. Other procedures such as gastric banding, biliary pancreatic diversion and gastric balloons make up less than 3% of procedures every year. Revisions may also be performed, about 15% of procedures. This may vary based on region and surgeon.
• Complications may differ depending on the type of surgery. Procedures that surgically change the anatomy of the GI tract are at risk for operative complications such as anastomotic leaks, breakdown of suture lines, hernias and obstructions. Procedures that externally affect intake of calories are at risk for band migration and balloon complications. Patients are at risk for the usual surgical complications such as infection or pulmonary embolism.
• Laparoscopic band procedures.
  • What early complications may result from this procedure? Up to 2% of these procedures will have band erosion or migration. These patients may present with intractable nausea/vomiting, poor weight loss and acid reflux. The diagnosis is usually made by Gastrografin radiographic study. This complication often requires revision or conversion to a non-reversible procedure such as a sleeve gastrectomy or Roux-en-Y gastric bypass.
  • What complications are likely to occur 1-2 months after surgery? Most of the laparoscopic band complications likely have passed. Complications may result from patients not adhering to dietary restrictions. Patients may have gastric dilation and poor weight loss.
• Roux-en-Y gastric bypass.
  • What complications may be seen early on in these patients?
    • The most feared complication is an anastomotic leak when the suture line breaks down and the connection of the small bowel to the gastric pouch opens. Unfortunately, the presenting symptoms can be vague and classic peritoneal signs may not be present. Instead, the patient may present with restlessness, back pain, pelvic pressure, low grade fever, low grade tachycardia and even hiccups. Have a high suspicion and low threshold for CT scan and early surgical consultation.
    • Pulmonary embolism is another consideration. This has a very high mortality rate in this patient population when present, up to 20-30%. The signs and symptoms can be similar to an anastomotic leak. Keep both complications in mind.
  • What complications can develop later in the postoperative course? The three most common complications are internal hernias, gastrointestinal bleeds from suture line issues and stomal stenosis.
    • Internal hernias and gastrointestinal bleeding are the most urgent as they can require emergent surgical or GI intervention.
    • CT scans are the best way to diagnose internal hernias.
    • For gastrointestinal hemorrhage, it is important to recognize that these patients may require more aggressive resuscitation as they have less oral intake than the typical patient. A small amount of blood loss may result in more extreme symptoms.
    • Patients with stomal stenosis may present with a sensation of fullness and discomfort in the upper abdomen. Swallowing study may confirm the diagnosis. Usually, these patients can be discharged for an outpatient dilation procedure.
  • Luber, SD et al. Care of the bariatric surgery patient in the emergency department. J Emerg Med. 2008 Jan;34(1):13-20. PMID: 17976784 Since this article was published, gastric sleeve procedures have become increasingly common.
  • Gastric sleeve procedures.
    • What complications can occur? This procedure is less technically challenging than Roux-en-Y gastric bypass. Patients may experience typical postoperative complications after laparoscopic sleeve gastrectomy. There are no changes in the anatomy of the GI tract aside from removal of portion of the stomach. The more feared complications such as anastomotic leak or internal hernia are unlikely. This is one reason that this procedure has become more common.
  • A patient presents with severe abdominal pain and peritoneal signs two weeks after a Roux-en-Y gastric bypass. What is your approach to this patient?
    • Do the ABCs. Make sure you have IV access. Begin fluid resuscitation. Do a careful history and physical examination. Send a broad laboratory evaluation including typical pre-operative labs. If the patient looks ill, do a CT scan. Evaluate the chest for pulmonary embolism and the abdomen/pelvis to rule out anastomotic leak or internal hernia. Get a definitive study and early surgical consultation. The bariatric surgeon may decide to go straight to the operating room to evaluate for complications.
  • A patient presents with complications two weeks after placement of a lap-band.
    • Band migration and erosion are common complications. A Gastrografin upper GI series will be the most high yield test. CT scans are limited in the lap-band patient.
  • Does your management change if the patient presents three months after the surgery? The likelihood of an anastomotic leak or pulmonary embolism is less although these can still happen. Complications such as internal hernias, staple line disruptions with bleeding and stomal stenosis can take place. Make sure the patient is adequately resuscitated and has a broad lab evaluation with low threshold for CT imaging and surgical consultation or follow-up.
  • What if the patient is presenting three months after a gastric sleeve procedure? These patients rarely present with complications. Complete the Have a low threshold for CT imaging, but know that the yield may be lower. Patients may experience complications outside the GI tract.
  • What other complications may occur? The most feared complication are neurologic complications due to vitamin deficiency, especially thiamine. Most common bariatric surgeries involve resections of large parts of the stomach. These patients need to be on continuous vitamin supplementation to ensure adequate levels. When these patients develop poor oral intake, they can present with the signs and symptoms of thiamine deficiency up to encephalopathy and death. Arvind reviewed a malpractice case against emergency physicians where a patient presented on multiple occasions with vague and progressive neurologic symptoms where none of the treating physicians, including a neurologist, realized the patient’s history of gastric bypass, vomiting and poor vitamin supplementation. If there are any concerns about oral intake, give them a dose of thiamine to make sure that this issue is covered. It is not just chronic alcoholics who experience Wernicke-Korsakoff syndrome. Any patient with chronic disease or bariatric surgery is at risk. There is minimal downside to treatment and you need to consider this diagnosis. Remember if you are treating Wernicke’s, the dose of thiamine is different [ note: e.g., 500mg for treatment vs 100mg for prophylaxis] than in prevention.