Risck and Benefits

While your motivation to have weight loss surgery likely stems from a desire to resolve medical problems and consequently prolong and improve your quality of life, it is important to understand the risks of these surgeries. Only by carefully considering these risks can you make an informed decision to have weight loss surgery -- whether it be gastric bypass, laparoscopic gastric banding or sleeve gastrectomy.

Before discussing these risks, we should emphasize that bariatric surgery is safe and effective, and that our designation as a Center of Excellence by the American Society for Bariatric Surgery attests to our superior outcomes and meticulous attention to detail.

No matter what surgery you and your physician choose, there are certain risks that are common to all procedures. Deep venous thrombosis (DVT) refers to a blood clot that forms in a vein, usually, but not always, in the leg. When pieces of this clot break off and travel to the lungs, this is called a pulmonary embolism (PE). Obesity in itself increases one’s risk of DVT and PE. As such, we take several precautions before, during and after the operation to prevent their occurence. In patients who have a history of DVT/PE, a “hypercoagulable” condition, a limited ability to walk, or who are deemed to be at significant risk for this complication, we often require a filter to be placed in the large vein that carries blood from your legs. This filter does not prevent the formation of a clot, but it can catch pieces of clot that break off before they enter the lungs. Also before surgery, we require that women stop taking birth control pills as they increase the risk of blood clots. In the operating room, we take several measures to avoid the formation of blood clots as well. All patients receive a small amount of blood thinner immediately prior to the operation. All patients wear compression stockings. And all patients have sequential compression devices (“leg squeezers”) placed over their lower legs. After surgery, we continue with these preventative measures. Most importantly, however, we encourage our patients to get up and move around. Walking is perhaps the best prevention for DVT. Despite all of these preventative measures, the incidence of DVT is 2% and pulmonary embolism remains the most common cause of death after bariatric surgery.

Another risk common to all operations is inadvertent injury to surrounding structures. While injury to any organ (liver, bowel, blood vessels etc.) may occur, bariatric surgeons are particularly aware of the spleen with its intimate attachment to the top of the stomach. Injury to the spleen may necessitate its removal. Although it has been shown that performing weight loss surgery laparoscopically, as we do, reduces the incidence of this complication, it still may occur in less than 1%.

Performing weight loss surgery laparoscopically also reduces the incidence of wound complications such as infection and hernia. The incidences of these complications after laparoscopic surgery are between 1 and 2% while they may occur in 5-15% of patients after weight loss surgery using a standard, large incision approach. Not all cases, however, can be completed laparoscopically. There is always a risk that the operation will be converted to an open procedure. If this is the case, the decision will be made during the procedure, but often will be anticipated and discussed with the patient based upon a history of multiple, previous abdominal surgeries. Even so, this occurs very infrequently in less than 1% of patients.

Clinically significant bleeding is another risk common to all surgical procedures. Certain medications may predispose you to bleeding. In your bariatric surgery packet, we have provided you with a list of these medications. Please review this list and notify your physician if you take any of them as these medications should be stopped three weeks before your surgery. Even if you do not take any of these medications, there is always a risk of bleeding during and after surgery. Clinically significant bleeding occurs in 1-2% of bariatric surgery patients. The treatment for this complication includes observation in the hospital with routine blood checks and may require blood transfusion or even reoperation.

Bowel obstruction after weight loss surgery may occur for several different reasons including internal scarring, hernias and technical error. Its overall incidence is approximately 2%. The treatment for this complication is almost always surgery, and 75% of those corrective operations can be performed laparoscopically. One particular type of hernia, called an internal henia, occurs only with the Roux-en-Y gastric bypass and involves a segment of intestine becoming stuck in certain spaces created by the Roux-en-Y anatomy. This occurs in less than 1% of gastric bypass patients but is important to note as it typically occurs several months or even years after the weight loss surgery.

Also unique to the gastric bypass are the complications of ulcers and strictures. An ulcer refers to an area of inflamed tissue, typically near the junction of your new pouch and the intestine, and occurs in 3-4% of patients after gastric bypass. These ulcers are much more common and often more virulent in people who smoke, and we encourage all of our patients to undergo smoking cessation prior to surgery. Complications of these ulcers include pain, bleeding and perforation – all of which may require surgical treatment. Fortunately, most ulcers are easily treatable with medication and rarely progress to that point. Continued smoking, however, often makes these ulcers refractory to medical treatment. A stricture refers to a narrowing of the opening between the gastric pouch and the intestine. This often will make it difficult for a patient to eat and consequently may lead to dehydration and malnutrition. Strictures occur in approximately 5% of patients after gastric bypass and are most often corrected with an outpatient procedure called an upper endoscopy. During this procedure, the physician places a camera through the mouth into your pouch and then inflates a balloon across the narrowing to stretch it out. Most strictures are amenable to this treatment, but persistent strictures require surgery.

The most feared complication of weight loss surgery is a leak. After the gastric bypass, leaks most commonly occur where the surgeon has attached two structures (i.e. your pouch to your intestine or your intestine to your intestine). After the sleeve gastrectomy, a leak would occur from the cut border of your stomach. Leaks are extremely rare after gastric banding, but may occur. We take several measures in the operating room to prevent this complication, but it may occur in between 1-2% of patients. If a patient has a leak, the treatment varies from in-hospital observation with medical support to emergency surgery.

There are certain complications unique to laparoscopic adjustable gastric banding. Of note, these complications more often require surgery but typically are not life-threatening. Because the adjustable gastric band must be placed in a particular way around the stomach, there is always the risk that it may slip out of place. This complication is appropriately called “band slippage”, the other term being “gastric prolapse.” This may cause a patient to have pain or vomiting and requires surgical correction. In 1-2% of patients, the band may erode into the stomach or esophagus and need to be removed. Problems may occur with the band hardware, namely the port which has been placed in the abdominal wall or the tubing that connects that port to the inflatable band. If the port flips and becomes inaccessible, it may need to be repositioned during an outpatient surgery procedure. If the port or tubing develops a leak of if the tubing becomes disconnected from the port, these will also require surgery. Once again, these are not life threatening complications, but they do require another surgical procedure. Very rarely, the band may become infected. This is a serious complication which requires surgical removal of the band.

The overall risk of death from weight loss surgery is less than 1%.

There are several long-term complications of weight loss surgery that reflect a patient’s commitment to the lifestyle modifications necessary for success. Primary failure of a weight loss surgery operation is very rare but may occur if a patient is poorly compliant with diet and exercise.

Additionally, if one does not adhere to the vitamin regimen after gastric bypass surgery, deficiencies will occur and may lead to death or permanent disability. After gastric bypass, vitamins are a lifelong requirement.

Finally, patients may suffer from gallbladder disease after weight loss surgey. Rapid weight loss predisposes one to the formation of gallstones and this in turn predisposes one to the development of gallbladder disease. Of note, laparoscopic removal of the gallbladder is one of the most commonly performed operations in the world, and previous weight loss surgery minimally, if at all, increases the difficulty of this operation.