Risks of Bariatric Surgery
Large amounts of blood loss rarely occurs with gastric bypass surgery and transfusion is very rarely needed.
Bleeding may be caused by inadvertent injury to the spleen during surgery. The spleen is located in the left upper abdomen, very close to the site of the surgery. The spleen is a fragile organ that can bleed easily if injured. Bleeding from the spleen can usually be stopped. In rare cases, the spleen must be removed. A person can live normally without a spleen, but will have to receive a vaccine after the surgery.
Because the risk of contracting HIV or hepatitis from a blood transfusion is less than one case per million units of blood transfused, and because bariatric surgery rarely requires transfusions, you do not need to donate your own blood prior to your surgery.
Blood clots in the legs (deep venous thrombosis) and clots that pass to the lungs (pulmonary embolus) can occur with any major abdominal operation. This is a rare complication of bariatric surgery, but it can be fatal. We give patients blood-thinning shots (heparin) before and after surgery, and use special compression stockings, to prevent this complication. However, such measures do not completely eliminate the risk of blood clots and pulmonary embolus.
All operations are associated with a small risk of heart complications such as heart attack or abnormal heart rhythms. This is very unusual in patients without symptoms of heart disease (history of heart attack, chest pain, pressure, heaviness, tightness and squeezing, or a known abnormal heart rhythm).
Older patients and patients who perform very little exercise are likely more at risk. If you have symptoms of heart disease, you must see a cardiologist to assess your risk prior to the surgery.
Patients who rely entirely on food for their happiness in life will not be satisfied with this operation. Some patients use food to cope with other problems in their lives and taking this away can lead to a great deal of stress.
Before surgery, think about the triggers that cause you to overeat, and work on healthy alternatives to eating. This operation will help you to maintain a strict diet. It will not allow you to eat whatever you want and still lose weight.
If you use food for comfort, eat because you are bored, stressed, or use food to protect yourself from others, it is very important to talk with a therapist before surgery to explore other ways of coping. A psychological assessment is part of each Bariatric Surgery program location's "Steps Before Surgery."
The risk of death is generally less than one percent with the initial operation and around two percent with re-operative gastric bypass surgery. Previous stomach surgery adds complexity to the procedure. These estimates are for the average patient who is otherwise in good condition, or who has medical problems that are well controlled. The risk may be significantly higher in patients with massive obesity or other significant medical problems.
Foods high in carbohydrates (sugars), lactose (milk products), or fat may cause symptoms such as dizziness, sweats, cramping, nausea, vomiting, or diarrhea. This is known as dumping syndrome.
Not everyone will have symptoms of dumping syndrome. Some patients get only mild symptoms; others will get severe symptoms.
Note: Dumping syndrome doesn't help you lose weight.
Foods such as candy, non-diet soda, milkshakes, or ice cream will often lead to dumping. While the side effects are unpleasant, it is in essence your body telling you not to consume these calorie-rich foods.
Rapid weight loss is a risk factor for the development of gallstones. If you have gallstones that are causing abdominal pain, your gallbladder will likely be removed at the time of surgery. If you do not have gallstones or have gallstones that are not causing pain, your gallbladder will not be removed.
If your gallbladder is not removed, you will be given a prescription for Ursodiol (Actigall), a medication that is taken for about six months after surgery and appears to reduce the risk of gallstone formation during the period of rapid weight loss. This medication costs about $175 a month, and is covered by most insurance companies that cover the cost of prescription medication.
Obesity is a major risk factor for a wound hernia, which is a bulge in the wound after surgery. Such hernias are usually repaired in an operation done after the patient has lost weight following bariatric surgery. It can be done sooner in the case of an emergency. The risk of a wound hernia with the open-incision method is 20 to 25 percent. It very rarely occurs with a laparoscopic approach.
It is also possible to develop an internal hernia with either open or laparoscopic surgery. Internal hernias do not cause a bulge, but can cause an obstruction of the small intestine. An internal hernia can occur at any time, even years after bariatric surgery.
Unexpected situations may be encountered during surgery that makes the surgery excessively risky. We have encountered a few patients with whom the surgery was begun but the gastric bypass was not done. Examples include a patient with severe cirrhosis of the liver (discovered during surgery) and a patient with an injury to the esophagus.
While the majority of patients have excellent results from the surgery and lose a large amount of weight, very small percentages have a lesser weight loss. This may be related to their dietary habits and other less well understood factors. Weight loss is not guaranteed after gastric bypass surgery.
An inactive lifestyle and failure to follow-up with the Bariatric Surgery Program after the surgery may result in less than satisfactory weight loss results.
Frequent snacking and eating a large amount of soft foods will lead to weight gain.
Intestinal obstruction (blockage)
In some cases, scar tissue or inflammation can narrow the new connection between the stomach and intestine. This is called a stricture. Strictures usually develop four to six weeks after surgery, and affect less than five percent of bariatric surgery patients. Patients with strictures will notice that they are progressively less able to take in fluids and food. Strictures can be treated with an endoscope, which is a thin, flexible tube with image sensors and special tools at the tip. A doctor will use an endoscope with a tiny inflatable balloon at its tip to open the stricture.
An ulcer may narrow the outlet of the pouch as it heals after surgery. The ulcer can obstruct the passage of food, or cause bleeding. Such bleeding is usually controlled by medications. To prevent ulcers, patients must take an acid-blocker (like Pepcid) for two months after surgery. If you are already on an acid-blocker, such as Prilosec, Nexium or Prevacid, you can continue this medication. In addition, all patients must avoid aspirin (unless you take aspirin for your heart or to prevent a stroke) and other medications that increase the risk of bleeding (such as ibuprofen, Advil) for two months after surgery.
Only in unusual cases is surgery needed to revise the stomach-intestine connection.
After any abdominal surgery, internal scars (adhesions) form in the abdomen. In rare cases, the lower intestine (bowel) can become twisted around an adhesion and cause an obstruction. This keeps digested food from passing through the body. An obstruction can happen at any time, even years after bariatric surgery. Because the obstruction must be repaired before the intestine loses its blood supply, an emergency operation may be necessary.
Most patients undergoing this operation have pain that almost disappears after two weeks. After any operation on the abdomen and chest, there is a rare risk of a chronic pain syndrome that is very difficult to treat. This is a very rare problem.
The connections the surgeon makes between the stomach pouch and small intestine, and within the small intestine, can leak after surgery. This can cause an infection in the abdominal cavity (peritonitis), and lead to an abscess, a collection of pus surrounded by inflamed tissue.
Leaking and infection are unusual complications of bariatric surgery, but they can lead to re-operation(s) and prolonged hospitalization.
Although patients receive antibiotics at the time of surgery, obesity increases the chances of wound infection (an infection at the site of your incisions). The wound may need to be partially or completely opened for treatment. Some patients may develop a seroma, or an accumulation of fluid at the incision site. Wound infection or seroma may take a few weeks to a few months to heal. The risk of wound infection is about 10%.
Women of childbearing age should not become pregnant immediately after gastric bypass. The period of rapid weight loss leads to nutritional deficiency that could harm the fetus.
Once a stable lower weight is achieved, usually after 12 to 18 months, patients can safely become pregnant. You must continue to take your required vitamins and minerals to ensure a safe pregnancy.
Talk to your primary care provider about birth control prior to surgery.
The period after gastric bypass with massive weight loss may be a very stressful time. Significant changes occur in body image and your relationship with others, including your spouse or significant other. This can lead to strained relationships, which may lead to depression, anger and, at times, divorce.
Some patients continue to feel obese, despite weight loss. Many patients mourn the loss of food, and food rituals. After surgery, some patients become depressed when they come to the realization that gastric bypass is not a cure for all of their problems.
Psychological counseling and screening is mandatory before your operation, and is highly recommended after.
Regular attendance at the Postoperative Graduate Sessions (Support Groups) in Lebanon and the Classes and Support Groups in Concord and Manchester may help you cope with the post-operative challenges after gastric bypass, and receive support and encouragement from people who have been in your situation.
The risk of lung complications after gastric bypass surgery is low. A breathing tube is used to administer anesthesia during the surgery, and in most patients, this tube is removed in the operating room or shortly after the operation.
Patients with massive obesity, severe deconditioning (becoming short of breath with minimal activity), obesity hypoventilation syndrome, and severe sleep apnea, may need to use a ventilator after surgery. Patients with severe breathing difficulties may require a tracheostomy (a breathing tube surgically placed in the neck), and weeks on the ventilator.
Although most patients with sleep apnea do well during surgery, and have their breathing tube removed after surgery, it is very important to be tested and treated to lower your risk of post-operative breathing problems if you think you have sleep apnea.
Atelectasis, a partial lung collapse at the bottom of the lungs that can lead to pneumonia, is possible after surgery. Patients will be given instructions to cough, take deep breaths, and use the incentive spirometer as instructed.
If you are a smoker, it is important to stop smoking at least eight weeks before surgery to reduce your risk of lung complications. Smoking is as much a risk to your health as morbid obesity, and is the leading cause of preventable death in the United States.
Strictures (narrowing between the stomach-intestine connection) / Ulcers
In some cases, scar tissue or inflammation can narrow the new connection between the stomach and intestine. This is called a stricture. Strictures usually develop four to six weeks after surgery, and rarely occur. Patients with strictures will notice that they are progressively less able to take in fluids and food. Strictures can be treated with an endoscope, which is a thin, flexible tube with image sensors and special tools at the tip. A doctor will use an endoscope with a tiny inflatable balloon at its tip to open the stricture.
An ulcer may narrow the outlet of the pouch as it heals after surgery or at any time after surgery. The ulcer can obstruct the passage of food, or cause bleeding. Such bleeding is usually controlled by medications. To prevent ulcers, patients must take an acid blocker (such as omeprazole) for 3 months after surgery. If you are already on an acid-blocker, such as Omeprazole (Prilosec), Nexium or Prevacid, you can continue this medication. In addition, all patients must avoid aspirin (unless you take aspirin for your heart or to prevent a stroke) and other medications that increase the risk of bleeding (such as ibuprofen, Advil) for two months after surgery, and then sparingly after gastric bypass. Drinking alcohol regularly and smoking increase ulcer risk.
Only in unusual cases is surgery needed to revise the stomach-intestine connection.
Since the stomach pouch is too small to allow adequate intake of vitamins and minerals, supplementation is crucial. You must take vitamins and minerals every day for the rest of your life to avoid nutrient deficiencies. If you do not plan to take the recommended vitamin and mineral supplements after surgery, you should not have gastric bypass.
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