Divided gastric bypass surgery is a major operation. As is true with any surgical procedure, there are risks which should be understood by anyone considering gastric bypass. Potential risks are the same as would be encountered by a clinically severe obese patient undergoing any other major abdominal operation. These may include heart attack, and possible (though rarely) death.
The entire list of complications and adverse effects may not yet be known. The level of risk depends upon the degree of obesity and co-morbid conditions such as diabetes, heart and or lung disease. Obesity and CO-morbid conditions can increase complications of both the surgery and anesthesia. Possible complications include respiratory problems, infection, cardiac complications, leaks where intestine and stomach are joined together, and blood clots in the deep veins of the legs. These clots occasionally migrate to the lungs. Less common complications include postoperative ulcers, obstructions and strictures of the various anastomoses.
The risks of gastric bypass surgery fall into two broad categories: Those occurring early in the postoperative period and those occurring later, after recovery from surgery.
Early Potential Complications
Among early complications of bypass surgery, respiratory problems are the most common. When a patient has CO-morbid conditions involving his or her respiratory tract, a pre-operative pulmonary evaluation with a specialist in pulmonary disease may be recommended. During the operation, special forms of anesthesia may be necessary to minimize pulmonary risk. Early walking will be recommended, beginning the night of surgery, and the head of the bed may be elevated. Frequent and early use of a device to encourage deep breathing (called an incentive spirometer) may help prevent pulmonary complications.
While rare, an anastomotic leak is serious and may, require an immediate return to the operating room for correction. When re-operation is required, the leaks are closed and additional drains are inserted. The patient may also be given a feeding tube so that nutrients can be passed into the intestinal tract below the leaking area, thereby allowing the anastomosis to heal. Alternatively, a drain may be placed by the radiologist in x-ray thus eliminating the need for additional surgery.
As with all major surgery, prevention and treatment of postoperative infections and wound separations involves the use of careful tissue handling, antibiotics and careful control of blood loss using advanced. surgical techniques.
Close attention is paid to controlling bleeding throughout the operation. Special effort is made to prevent bleeding from the spleen and other structures. In spite of all our precautions, there remains a very small chance of bleeding during or after the surgery where transfusion, re-operation and sometimes removal of the spleen will be required.
Blood clotting in the leg veins and clots migrating to the lungs may occur and are potentially serious. This problem increases in frequency with the degree of obesity. To reduce the likelihood of clots in gastric bypass patients, low dose heparin injections (blood thinners) are used to prevent clots from forming during periods of maximum risk. Additionally, inflatable boots or stockings and frequent ambulation after surgery help to decrease the risk blood clots.
Read more about the postoperative procedures at Missouri Bariatric Services.
Late Potential Occurrences
Other undesirable conditions may occur months or even years following gastric bypass surgery. These may include:
- Weight gain caused by enlargement of the pouch due to overfilling by the patient.
- Incisional hernia or the pulling apart of small sections of the abdominal wound months after the operation caused by the tremendous pressure on the wound in a very obese abdomen. In patients over 300 pounds, this complication may occur in a large percent of cases. Usually, it can be easily repaired by another relatively minor operation.
- Bowel obstruction caused by adhesions (scar tissue) can occur late after gastric bypass surgery, as it can after any abdominal operation.
- Ulcers at the site of the stomach or intestinal anastomosis (stomal ulcer) or acid peptic ulcers in the non-functional large stomach pouch occur in 2 to 4 percent of patients, not unlike the incidence in the general population. Stomal ulcers are often caused by smoking, overeating, aspirin or non-steroidal anti-inflammatory drugs. The use of cortisone in the postoperative period may also lead to a higher incidence of ulcer disease. When ulcers do occur after gastric bypass surgery, they can be treated with medications such as Prilosec, Prevacid, Protonix, Tagamet or Zantac.
- Constipation may occur after surgery. Remember that food intake now is very small compared to that prior to surgery, therefore bowel movements will be decreased. Many people report having a bowel movement every two to three days. If stools are hard, be sure to drink an adequate amount of fluid (46 to 54 ounces per day). More fiber-containing foods may be added to the meal plan. If a high fiber addition is insufficient to correct the condition, the physician may recommend a stool softener.
- Gallstone development is related to rapid weight loss and is most likely to occur in the first 6 to 18 months after surgery. Gallstones are not a complication of the surgery as such, but are related to the problem of clinically severe obesity in general. In the 20 to 30 percent of patients who develop gallstones, surgery may be necessary. These operations can usually be done by a laparoscopy, which uses microsurgical instruments and a small incision.