Risks, Complications, and Side Effects

Bariatric Surgery Risks, Complications, and Side Effects

More than a third of the adult population in the United States is considered to be obese according to the Center for Disease Control and Prevention (CDC), translating into 78.6 million adults. Along with obesity come a number of associated illnesses and health issues that must be attended to every year. Individuals that are considered to be obese might suffer comorbidities such as heart disease, type 2 diabetes, stroke, and a variety of cancer types. In addition, there may be damage to the joints, muscles, and bones of obese individuals. In the United States, an average of $147 billion dollars was spent in 2008 alone on medical expenses related to the obesity of citizens.

Obesity is considered to be present in an individual if their body mass index (BMI) is greater than 40 kg/m2 or greater than 35 with accompanying obesity-related comorbidities such as diabetes or heart disease. Individuals that are considering bariatric surgery must be within this range and must have attempted and failed at other supervised weight loss efforts. The individual must also be healthy enough to withstand the surgery and prepared for the life changes that must be made in order for the surgery to be successful in the long term relating to weight loss.

Many patients that are deemed to be obese are considered good candidates for bariatric surgery options. Some of the surgeries include a gastric sleeve, duodenal switch, gastric banding, gastric plication, gastric bypass, and mini-bypass. As with all surgeries, there are related complications and risks that should be considered before agreeing to surgery. Here you will find information about each of the surgeries and the complications and risks associated with them.

Gastric Sleeve Complications & Risks

While the complications and risks are similar to those with other bariatric surgeries, there are some that are different.

Some of the complications and risks associated with gastric sleeve surgery include:

  • Leaks at the staple lines or seals;
  • Infection from the surgery;
  • Internal bleeding due to the surgery;
  • Psychological conditions relating to sudden weight loss;
  • Depression: the inability or desire to do daily activities;
  • Blood clots: clotting or clogging of the blood within the veins;
  • Lung and breathing difficult;
  • Anesthesia reactions: an adverse reaction to the medication used to put you to sleep;
  • Malnutrition: this is a lack of nutrition caused by a lack of absorption of the nutrients from food eaten by the patient;
  • Stomach perforation: this might be small holes in the stomach due to the procedure;
  • Low blood sugar or hypoglycemia immediately following surgery;
  • Bowel obstruction: inability to pass stools due to something in the way within the body;
  • Hernia: a protrusion or disfiguration of the area;
  • Gallstones: stone-like particles that vary in size, created in the gallbladder from leftover particles that do not pass through the body;
  • Ulcers: a lesion on the interior of the stomach or another part of the body, often causing pain and blood;
  • Dumping syndrome following surgery: when the body can not digest the food due to too much food, it might expel the food rapidly with vomiting, cramping, diarrhea, and fullness shortly after eating;
  • Rarely, death.

Common Complications of Gastric Sleeve

Percent of Complications by Patients undergoing Vertical Sleeve Gastrectomy

Of the complications that can occur, 1.2% of patients suffer from bleeding, 2.2% of patients account for leaks and .6% of patients account for stenosis. The mortality rate for patients undergoing gastric sleeve surgery is approximately .19% according to recent studies. This is fairly low compared to the overall numbers related to bariatric surgery in general and the risks associated.

Dr. Louisiana Valenzuela Complications vs National Average (for 2014)

2014 Comparison (Percent)DeathLeaksBleedingStenosis
Dr. Valenzuela0%0.02%0.012%0%
Study Average0.19%2.2%1.2%0.6%


Food Related Complications

In addition to the surgery complications, there are also issues relating to the types of foods that the patients are able to eat after the surgery. Since there is a limited amount of space in the stomach there may be some issues with spicy foods and those foods high in carbohydrates. A reduction in the production of the hormone that expresses hunger, ghrelin, may also cause patients to have less of an appetite.

While most individuals tolerate the surgery well, there are those that suffer complications. Those individuals that are severely overweight may also find that gastric sleeve surgery is only a step and duodenal switch surgery is the next step in the process to complete the weight loss challenge ahead. There are also some changes that will need to be made regarding the food approach.

Gastric Bypass Complications and Risks

Gastric Bypass Surgery
Gastric Bypass Surgery

There are complications and risks involved in gastric bypass procedures as with other surgeries of this nature. Since the operation is clearly more involved than similar surgeries, there can be more overall risk involved. The typical mortality rate for this procedure is between .2% and .5%. This is compared to the overall mortality rate of .135% for bariatric procedures. Some of these are short-term and due to the actual surgery while others are term issues that will need to be dealt with over time. Some of the possible complications and risks might include:

  • Pulmonary embolism: the blockage of one or more of the pulmonary arteries with the lungs often caused by a blood clot;
  • Leakage from connections and staples;
  • Obstruction of the small bowel;
  • Bleeding;
  • Blood clots: a clotted piece of the blood in the veins;
  • Hypoglycemia: dangerously low blood sugar, typically below 70 milligrams per deciliter;
  • Deficiency of vitamins and minerals;
  • Gastroesophageal reflux disease (GERD): stomach acid backs up into other areas of the body including the esophagus;
  • Stenosis: a narrowing of hard valves;
  • Gallstones: stone-like particles that vary in size, created in the gallbladder from leftover particles that do not pass through the body;
  • Ulcers: a lesion on the interior of the stomach or another part of the body, often causing pain and blood;

In a study conducted by the University of Iowa in July of 2009 out of 38,501 bariatric surgery patients, 93 died within a 30-day mark, primarily from pulmonary embolism (.078%), leaks (.036%), and small bowel obstruction (.02%). While this is not common it is something that should be considered. Out of 3,258 patients having gastric bypass in a study conducted, 97 of them had complications of infection. This compares well when considered against 513 open surgery patients with 34 of them having wound infections.

Nutritional deficiencies are seen in many patients. Between 13% and 52% of patients undergoing gastric bypass, see an iron deficiency occur within the first two to five years after the surgery completion. This is one reason that as many as 37% of patients are prescribed a multivitamin after surgery. Calcium deficiencies are also fairly common occurring in up to 10% of patients and vitamin D deficiency in up to 51%. Of 109 bariatric surgeons surveyed, 96% stated that they prescribed their gastric bypass patients multivitamins after the surgery.

The rise in gallstones in patients undergoing Roux-en-Y gastric bypass is between 38% and 52% within the first year. An average of between 15% and 28% of patients need a cholecystectomy urgently within the first three years following the surgery. Another number to consider is that of the rate of deep vein thrombosis that occurs in patients after this surgery. The range is between 0% and 1.3%. Of those deaths that did occur in gastric bypass patients, 50% have been due to pulmonary embolisms.

Gastric Banding Complications and Risks

Gastric Banding Surgery

There are complications and risks associated with gastric banding both during the surgery and after. Not all of them are serious in nature and some of them are long-term rather than simply immediate post-surgery issues. Some of these include the following:

  • Infection from the surgery;
  • Band slippage requiring additional surgeries to correct the problem;
  • Deflation of the balloon used in the band;
  • Excessive and dangerous bleeding;
  • Stomach pouch enlargement: when the new pouch enlarges too quickly;
  • The outlet of the stomach or the stoma could become blocked;
  • GER or gastroesophageal reflux: stomach acid backs up into other areas of the body including the esophagus;
  • Discomfort from the banding;
  • Nausea;
  • Dumping syndrome following surgery: when the body can not digest the food due to too much food, it might expel the food rapidly with vomiting, cramping, diarrhea, and fullness shortly after eating.

Out of the patients that have gastric banding surgery, between 0.8% and 12% suffer from complications from the surgery. These include bleeding at a rate of 0.1%, which is clearly a rare occurrence. Wound infections in lap banding patients are comparable to gastric bypass and the deep vein thrombosis risk sets at 0.01% to 0.15% and pulmonary embolism at a rate of 0.1%. The problem of erosion of the belt seems to be improving with the latest numbers showing that 4.7% of 600 patients showed signs of erosions. The mortality rate for patients partaking in gastric banding is reported at between 0% and 0.7%. Of 64 studies involving 8,504 patients, malfunctions of tube or port that required re-operative surgery accounted for 1.7%, band erosion was reported in 0.6% of these individuals, and band slippage or pouch dilation accounted for 5.6% of these accounted for.

Duodenal Switch Complications and Risks

Duodenal Switch Surgery

Since the duodenal switch surgery is fairly involved, there are some risks that could be considered substantial to be concerned with. Some of the possible complications and risks of a duodenal switch surgery include the following:

  • Excessive bleeding;
  • Infection;
  • Blood clots: a clotted piece of the blood in the veins;
  • Dehydration caused by swelling around the small bowel and the stomach;
  • Leaking of bile into the stomach;
  • Liquid consumption difficulty after surgery;
  • Rarely, death;

In addition to the short-term complications that could face from the duodenal switch surgery, there are some long-term risks and complications to be aware of.

  • Deficiencies in nutrition: lack of proper vitamins and nutrients;
  • Severe chronic diarrhea: consistent passing of soft stools;
  • Malabsorption of calcium and vitamin D related to brittle bone and osteoporosis;
  • Carbohydrate absorption causing weight gain;
  • Unpleasant smelling gas and stools.

Studies indicate that the mortality rate for duodenal switch surgery is 0.135%, which is similar to other bariatric surgery types. While the duodenal switch surgery is somewhat more complicated, it does not seem to pose any additional danger to patients when it comes to mortality. This being said duodenal switch surgery is often performed on morbidly obese patients. With this type of obesity patients often suffer from comorbidities at a higher rate than others. This can pose risk during a surgical procedure. A 2002 sturdy of patients that have had duodenal switch surgery indicated that approximately 5% opted to reverse the surgery.

Gastric Plication Complications and Risks

Sleeve Plication

Much like other surgeries, there are complications and risks to be considered. Some of these complications and risks include the following:

  • Leakage of the stomach from the various folds;
  • Stretching and expansion of the stomach;
  • Rupture from stretching;
  • Stomach blockage: the blockage could ;
  • Suture rupture: the sutures could rupture from pressure if the patient eats too much;
  • Bleeding;
  • Blood clots: clotting areas of blood in the veins often stopping the blood from moving;
  • Organ damage;
  • Infection.

When it comes to complication rates with gastric placation surgery, 15.1% of patients had complications in a study conducted in 2012 in the UK. There was an approximate 3% reoperation rate most often due to gastric obstructions. Of that complication rate, 1.5% was due to leaks resulting from suture line ruptures, hernia, and gastric fistula. Since the procedure is just gaining in popularity, there is still relatively little data regarding the complications and risks associated with the procedure in a wide spectrum. As more studies are conducted new information will help professionals to better understand the benefits and risks associated with this procedure.

In Summary

While all weight loss procedures can be risky, the patient must assess the weight loss risks and complications with the potential benefits. Most of the surgeries help individuals to reach an excess body weight loss of 77% when the process goes well. Avoiding some of the complications and risks involved means following surgical directions and making sure that you are prepared for the commitment that must take place after the surgery. Lifestyle changes are necessary if you hope to be successful in a weight loss endeavor that requires surgery.

The death risk for patients that undergo bariatric surgery of any kind increases with age. Studies have shown that patients over the age of 55 years held a threefold higher mortality rate than the patients that were younger. This news is considering that they had similar complication rates. The older patients most often fell prey to sepsis. In a study that monitored 16,155 Medicare patients undergoing bariatric surgery and with 81% of those undergoing Roux-en-Y gastric bypass, older males, as well as lower surgeon volume, was related to the higher risk of death early on. The mortality rate after thirty days showed to be 2.0% and after 90 days 2.8%. Those patients over 65 years found an increase in the numbers to 4.8% and 6.9%. This was higher than the younger patients that had numbers of 1.7% and 2.3%.

Morbid obesity can dramatically reduce the lifespan of an individual by as many as 13 years if the BMI is over 45. In a study by Christou et al in 2004, patients that had their weight medically managed suffered a 16.2% mortality rate over the 0.68% of those undergoing surgery. That weighs out to be an 89% reduction in risk for those with surgery over those without. Long-term survival for patients that have surgery increased to 33% from 27% prior to surgery.

In addition to being extremely beneficial with regard to lifespan and quality of life, the Centers for Disease Control and Prevention stated in 2000 that the total cost of obesity was $117 billion dollars per year. The savings of quality bariatric surgery is clear. Patients that succeed will find that there is a great deal of health benefit to making sure that the diet is followed and that the surgery is taken seriously. Proper exercise and good follow up to make all the difference in the end results. The patients that have long-lasting results are those that follow the directions of the plan and make major changes aside from the surgery.

Before deciding that bariatric surgery is the way to approach your weight loss efforts, discuss the options with your physician. You will want to make sure you are a good candidate for these procedures and that your physician can provide you with information that is going to help you with your decision. While each of the procedures has its own complications and risks to be concerned with, they also all have benefits to be considered. The weight loss that comes with most of the surgeries is undeniable and as long as you are willing to change the way you live your life, you may find them to be beneficial options. They might have additional suggestions beyond the surgery that can help you.

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Dr. Louisiana Valenzuela Boasts No Patient Complication Rates for the 2014 Year