Risks of Weight-Loss Surgery

1. Lung Problems

a. Atelectasis

Atelectasis is the partial collapse of the lungs. Atelectasis is very common after surgery, especially in obese patients, when the bottom portion of the lungs are "squashed" and open only with coughing and very deep breaths. This can lead to such problems such as fever, pneumonia, or shortness of breath. Atelectasis can be prevented or treated by performing deep-breathing exercises and by coughing.

b. Pulmonary Embolism

A pulmonary embolism is a blood clot in the lungs. The problem actually begins in the legs, where blood clots can form in the veins of the calves or thighs, especially if the legs are stationary. Such clots can cause leg swelling or pain. However, they present the most danger if they break off and travel to the lungs. A large clot can cause shortness of breath or completely block blood from entering the lungs, causing death. Overweight patients have a higher risk of forming blood clots in the legs, particularly during or soon after surgery.
To prevent pulmonary emboli, during and after surgery, your legs will be fitted with sequential compression boots, which act like blood pressure cuffs that massage your legs and prevent blood clots from forming. A small dose of blood thinner, called heparin, is given at the time of surgery. The best prevention is to get out of bed and walk soon after surgery.

2. Leakage of Bowel Contents

Leakage of bowel contents - from the new connection between the stomach and the small intestine or between two parts of intestine - is the most serious complication of gastric bypass and biliopancreatic diversion. Leak from a burst staple line in the sleeve gastrectomy can also occur. Such leaks can cause a high heart rate, pain in the abdomen or back, fever, infection, and even death. Treatment usually entails antibiotic therapy or surgical repair, depending on the size of the leak.

3. Blockage of the Stomach Remnant

In the Roux-en-Y gastric bypass, a new stomach pouch is made from top of the stomach and the rest of the organ is detached and left alone. The stomach remnant remains alive, but it shrinks in size. In rare instances, a blockage can develop in the stomach remnant, causing back-up of fluid and leakage of bowel contents. This condition can be difficult to diagnose because it does not cause vomiting. However, it may cause persistent hiccups or left shoulder pain, in which case you should call your surgeon. You would then need to have an abdominal CT scan. If the stomach is seen to be inflated, it will be deflated with a small needle using local anesthesia. This does not apply to the other operations.

4. Narrowing of the Stomach Pouch Outlet

In gastric bypass surgery, the connection between the new stomach pouch and the intestine is created with a stapling technique. With all healing, there is scar formation similar to a scab. Sometimes, this scar can tighten around the connection and cause it to narrow to a point where food cannot pass through. This problem typically occurs four to six weeks after surgery. It can be treated by stretching the narrowed opening, which is done endoscopically by a gastroenterologist.

In sleeve gastrectomy patients, the ‘banana-shaped’ stomach may become too narrow due to scar tissue, leading to difficulty eating or even drinking. Stretching by endoscopy may be necessary, or in extreme cases, corrective surgery.

In gastric band patients, the opening between the upper and lower stomach pouches can also become too narrow. This can be corrected with a simple band adjustment to loosen the band.

5. Wound Infection

As with any surgery, the incision site can become infected. In overweight patients with more fat in the abdominal walls, the infection can be deeper than usual. Minor infections are treated with oral antibiotics. Deeper, more serious infections may require opening the wound and packing it with gauze, in addition to antibiotics.

6. Band Slippage

In gastric band surgery, a band is placed at the top of the stomach and held in place by sewing the stomach around it. In rare instances, the band can slip and cause constant regurgitation and heartburn. Symptoms are relieved by loosening the band in the office. The diagnosis is confirmed with a barium-swallow study. If this happens, the band would likely need to be repositioned with another operation, laparoscopically. A special diet of liquids, shakes, and purees, followed for the first month after surgery, helps prevent this condition.

7. Band Erosion

On rare occasions after gastric band surgery, the band erodes into the stomach. This does not cause pain, but may result in inadequate weight loss. This is diagnosed by endoscopy. The condition is repaired with surgery, which is performed laparoscopically