Bariatric Surgery Complications &
11 Ways to Minimize
Bariatric surgery complications affect about 15% of patients1. Complications range from minor to severe and could be a single event or chronic in nature. This page will help you compare and minimize your risk of complications associated with each type of weight loss surgery.
- Factors that increase your risk for complications
- 11 Ways to Minimize your risk
complications by type of bariatric surgery
- Patient experiences with complications (please share your own as well)
- A to Z List of Potential Complications - Complete list, definitions & treatments
Bariatric surgery dramatically improves or cures many obesity health problems. But some of the same problems you’re trying to improve -- as well as working with an inexperienced surgeon -- can increase your risk for complications (definitions of bariatric surgery complications can be found further down the page)...
- The higher your body mass index (BMI), the more likely you are to have bariatric surgery complications. Some surgeons will want you to begin a physician-observed bariatric diet and weight loss surgery exercise program as soon as possible to reduce your weight prior to surgery (however, many bariatric surgeons do not require that you lose weight prior to surgery).
- Obesity-related health problems prior to surgery are directly correlated with developing complications in the first 180 days following surgery.2 An additional obesity health problem prior to surgery is associated with…
- Sleep apnea and gastroesophageal reflux disease (GERD) are
the pre-operative conditions that result in the highest risk for
bariatric surgery complications.
The scoring system...can help reduce post-surgical bariatric surgery complications by 65% and hospital readmission rates by more than 80%.
- Diabetes, sleep apnea and arthritis can determine your risk for sepsis.
- If you have had deep vein blood clots ( blood clots in legs or arms ), a pulmonary embolism or clotting problems in the past, you have a higher risk of experiencing them following bariatric surgery.
- High blood pressure prior to surgery can increase your risk of blood clotting problems after surgery.
- Working with a less experienced surgeon increases your risk of complications and mortality. For example...
- One study of over 15,000 patients found that the more cases a surgeon worked on, the lower the rate of serious complications:31
|# of procedures performed by surgeon over 3 years||Rate of serious bariatric surgery complications occuring within 30 days of surgery|
|Less than 100 cases||3.8%|
|100 - 249 cases||2.4%|
|Greater than or equal to 250 cases||1.9%|
- Another Pennsylvania study of over 14,700 patients from 1999 to 2003 showed similar results:32
|# of gastric bypass procedures performed by surgeons and hospitals over 5 years||In-hospital mortality rates||30-day mortality rates|
|High volume surgeons (>50 surgeries) at high volume hospitals (>300 surgeries)||0.12%||0.30%|
|Low volume surgeons (<50 surgeries) at low volume hospitals (<125 surgeries)||0.57%||0.98%|
Talk to your surgeon about how your specific health issues could impact your risk for bariatric surgery complications. More specifically, find out if they can obtain access to one or more of the following (share this page with your surgeon):
- Metabolic Acuity Score (MAS) - Recently developed by researchers from Arizona, this scoring system rates your risk on a scale of 1 to 4 and, according to the researchers, “can help reduce post-surgical complications by 65% and hospital readmission rates by more than 80%.”
- Obesity Surgery Mortality Risk Score (OS-MRS) - This similar test has been devised by a weight loss surgery program director from North Carolina. It measures patients' risk of being one of the less than 0.2% who die from surgery complications within 30 days following the procedure.
- M-SCORE VTE Risk Prediction - Uses a series of risk factors to help surgeons choose the best procedure based on patient risk level and to identify risk factors that can be reduced prior to surgery.
Whether or not you are more predisposed to bariatric surgery complications, there are 11 things that you can do to reduce your risks...
- Pick a good
surgeon and ask all the right questions. This is the most
important point by far.
Most surgeons offer free seminars that teach you about your options and their office's specific results. The seminars also allow you to get to know the surgeon prior to a one-on-one consultation (usually free as well).
Click here to find and schedule a free in-person seminar or one-on-one consultation with a qualified weight loss surgeon in your area.
- You can also review our How to Choose the Right Bariatric Doctors & Bariatric Weight Loss Center page to learn how to interview and choose the best surgical team.
- Most surgeons offer free seminars that teach you about your options and their office's specific results. The seminars also allow you to get to know the surgeon prior to a one-on-one consultation (usually free as well).
- Follow your doctors' and nutritionist's/dietitian's advice to the letter.
- Educate yourself about what to expect before, during and after surgery. Beginning this life-changing process with complete awareness is key to a successful outcome. Bariatric Surgery Source (this website) will give you the knowledge you need to be prepared.
In addition, talk with a few patients of your chosen surgeon. Find out what issues they experienced and consider how their stories could apply to you. Good bariatric surgeons will be happy to refer you to some of their patients.
- Educate your family and close friends about the changes you will experience. Their understanding of your new habits and the reasons you have decided to move forward with surgery will make it much easier to stay on track.
- Lose as much weight as possible prior to surgery. The lower your body mass index (see our Body Mass Index Formula page), the lower your risks. However, weight loss prior to surgery is a challenge for some patients, and many bariatric surgeons do not require it.
- Eat a healthy bariatric diet in the months prior to surgery.
- Get tested for sleep apnea syndrome several weeks before surgery. Sleep apnea signifantly increases surgical and post-surgical risks. As long as it's diagnosed prior to surgery, it can be treated ahead of time to reduce the risks. This is an especially big deal considering that - according to a UC Davis School of Medicine study of over 1,300 prospective patients - as high as 25% of prospective patients had UNDIAGNOSED sleep apnea prior to surgery.33
- If you have surgery out of your area, plan to stay close to your bariatric surgery center and surgeon for at least 10 days (preferably 2 weeks) after surgery. The two weeks immediately following surgery are the riskiest. If any bariatric surgery complications arise, you want to be close to the doctor who performed the surgery for advice and treatment.
- Exercise as soon as possible after surgery - the quicker you can get up and moving after surgery the better. However, you don't want to overdo it, so talk with your doctor and review our Exercise for Bariatric Surgery Patients section to learn an appropriate program.
- Use compression stockings, pneumatic compression devices (special machines that gently squeeze your legs to help keep the blood flowing) and blood thinners after surgery to reduce the risk of a blood clot. Your surgeon should have each of these available after surgery.
- Have and use
an effective support system
of family, friends, a good in-person
weight loss surgery support group and a well-rounded online
weight loss support group. It is nearly
impossible to succeed without the support of those close to you, and
your chance of long-term success increases greatly if you’re able to
talk with others who understand and will listen without passing
YOUR Weight Loss Journey
Help visitors like you by sharing your advice related to this page or other topics...
The following chart reviews the bariatric surgery complications that could arise as a result of each weight loss surgery. Certain complications are a risk for all surgical procedures, regardless of whether the procedure is related to weight loss. We have left these “general” risks out as well as the more rarely seen weight loss surgery complications.
This chart is meant to give you an initial understanding of potential surgery complications. You will work directly with your bariatric doctors to make a final determination of your potential risks. In addition, just because a box is not checked does not necessarily mean that your chances of having that problem are zero.
Notice that restrictive procedures that use an implanted band (lap band surgery and VBG) have similar bariatric surgery complications. But just because these two procedures have similar possible complications doesn't mean that they're the same. Gastric banding has been shown to be a much more effective procedure than VBG with lower complication rates in most cases.
Likewise, procedures that alter your digestive system (gastric bypass, duodenal switch and mini gastric bypass) are similar in regards to their types of bariatric surgery complications, but the rate of each complication may differ in frequency and severity.
Out of all the procedures, gastric banding (lap band surgery) appears to have the lowest level of and least severe bariatric surgery complications. The trade-off is less weight loss.
The gastric sleeve is in a class of its own as it is purely restrictive but uses no band. It may be a "best of all worlds" procedure with similar weight loss as gastric bypass with the lower and less severe complication rate of gastric banding. We are extremely excited about it, but more research is needed to confirm that GS works over the long-term.
See our Types of Bariatric Surgery page for a broader comparison of all procedures.
As bariatric surgeons’ techniques, research and experience develop, bariatric surgery complications continue to decrease.
Currently, about 15% of bariatric surgery patients will experience complications according to a recent study by the Department of Health & Human Services’ (HHS) Agency for Healthcare Research and Quality (AHRQ).1
Still have questions or concerns about
bariatric surgery complications?
If you finish reading this page and still have questions or concerns, our weight loss surgery community will be happy to help.
Regarding major adverse bariatric surgery complications (the development of blood clots in the deep veins of the legs or in the pulmonary artery of the lungs, repeat surgeries or failure to be discharged from the hospital within 30 days of surgery), only about 4% of patients experience one or more of them.3 However, the bariatric surgery mortality rate is extremely low at 0.135%.4
When evaluating bariatric surgery complications, it is important to keep in mind the risks that you are avoiding by having surgery. In addition to the health problems addressed by weight loss surgery, morbidly obese people who receive bariatric surgery are 89% less likely to die over any 5 year period than morbidly obese individuals who don't have surgery.5 (See our Life After Weight Loss Surgery page for more about which health problems are improved or eliminated following surgery.)
Your Experiences with Bariatric Surgery Complications
Please share the bariatric surgery complications you experienced or are concerned about. Your experiences will help other patients make decisions and avoid pitfalls.
Include anything related to bariatric surgery risks, complications or side effects, such as...
- Which procedure did you have/are you considering?
- Which problems did you experience/are you concerned about?
- Which did your doctor say you were at risk for? How did that compare to what actually happened?
- What did you do/are you doing to minimize your risk?
- How have you addressed the problems?
Other visitors' experiences with/thoughts about bariatric surgery complications
Click below to see contributions from other visitors to this page...
Lost 275 Lbs in 7 Months After Gastric Bypass But Have No Energy & Feel Sick Daily
I had gastric bypass in September of 2014. I started off at 425 pounds, I am now at 275. I am very proud of the weight I have lost. I take my vitamins …
Worried About Complications & Recovery After Gastric Sleeve
I am considering having the Gastic Sleeve surgery in a month's time and am worried about avoiding complications and giving myself enough time to heal before …
Loud Stomach Growling After Gastric Bypass
I had the gastric bypass done in 2004. Within the past 2 years I noticed that I can hear my stomach emptying (loud growling / gurgling) and my food moving …
Risk of Leaks After Gastric Sleeve
After you have the gastric sleeve, how long is there a risk of leaking? Do leaks happen frequently after the sleeve? What can the surgeon do to minimize …
Sugar Causes Vomiting for 3.5 Year Gastric Sleeve Patient
I had a gastric sleeve surgery in April 2011 and have been experiencing frequent vomiting spells (1x week) usually after eating sugar. I had some episodes …
Rapid Refill of Lap Band After Draining
I had lap band surgery five years ago and lost almost 100 pounds. I had been seeing different Doctors for a depression issue and unfortunately they just …
Stomach Pain 3 Months After Gastric Sleeve Surgery
I had the gastric sleeve surgery about 3 months ago. Before surgery I had GERD really bad and was taking prilosec daily. Since the surgery, I have had …
Roux-en-Y Gastric Bypass Blockage
I had Roux-en-Y gastric bypass in October 2008, and I haven't really followed my doctors advice in the last year or so. My question is, 1 yr ago I had …
Could These Be Side Effects from Lap Band Surgery?
My wife is coming up on a year having her band filled. In the last couple of months she has started being extremely cold all the time, has bruising on …
Questions About Switching from Lap Band to Sleeve
Three years ago I had a lap band put in and did relatively well. I had back surgery and gained almost 100 lbs during the ordeal. I had never been grossly …
My Gastric Band Tube Detached from My Band: Am I In Danger?
I had my band fitted March 2011 in Kent, I received excellent care during the procedure and following the procedure the surgeon arranged for me to have …
Gastric Bypass After Gastric Sleeve: Complications
In September of 2012 I had Gastric Sleeve Surgery but dealt with severe Acid Reflux. My Bariatric Surgeon did two Endoscopies to see if the opening needed …
Acid Reflux & Dry Scratchy Throat Years After Lap Band Surgery
I had lap band surgery several years ago and recently have been experiencing acid reflux and now a dry scratchy and slightly sore throat. I have been …
Can Gastric Bypass Cause Chronic Bad Breath?
I am considering gastric bypass but I have a friend who had the surgery two years ago and is at goal weight. I have noticed his breath smells bad some …
New Gurgling Sound in Throat & Stomach for Lap Band Patient
My throat and stomach now gurgle with everything I eat or drink. Is this a problem? I have not had a lap band fill in over a year and a half. I had …
Wife Losing Too Much Weight & Can't Keep Food Down Since Gastric Sleeve Surgery
My wife had bariatric surgery (vertical sleeve) last March, and now she cant keep anything down. Food, water it doesn't matter. The doctors have given …
Heartburn for the First Time 27 Years After VBG (Vertical Banded Gastroplasty)
It's been 27 years since my VBG (Vertical Banded Gastroplasty). For the first time, within the last 2-3 weeks I've experienced a burning/uncomfortable …
After Gastric Bypass I Feel Like I Have a Hair Ball in My Throat
I had gastric bypass 1 month ago and now I feel like I have a hairball or cotton in my throat. Why is that? Other than that, I am doing great.
Can my liver be bruised from gastric sleeve surgery?
I was sleeved on Apr. 23rd. It was done laparoscopically. I had elevated liver enzymes prior to the procedure was was given the ok for surgery. The …
Is converting the gastric sleeve to the gastric bypass an effective solution to chronic gastritis and GERD?
My name is Liz and I am 3 months post-op of the gastric sleeve surgery. I decided to have the gastric sleeve surgery after being recommended for it by …
Soft Stools 2 Years After Roux en Y Gastric Bypass
I had the Roux en Y gastric bypass done about 2 years ago. Since then my stool has changed. It is always very soft I also get diarrhea a lot. This past …
Long-Term Solution After Failed Lap Band
I underwent a lap band procedure 2 and a half years ago. I lost only 7 kg and regained the weight back. Now I have knee problems and back problems and …
Slipped Band - How Do You Know?
I am worried that I have a slipped band, but how can I know for sure? I had lap band surgery in January 2010 and have had really bad reflux lately (as …
Help me STOP losing too much weight after DS surgery!
I had BPD/DS surgery in 2004. At the time of surgery I weighed 380 lbs, and I have lost a total of 222 lbs (so far). My problem/concern is what can I …
Cord from port to lap band entangled her bowel
My Mum had lap band surgery in 2006. She had no weight loss success with it. She had to have the band removed after the plastic tubing from the port …
Feeling of Something Twisting Inside After Gastric Bypass Surgery
I'm wondering if the feeling of something twisting inside is related to my gastric bypass surgery... From time to time I feel a pain just under the …
Dilated esophagus and achalasia after lap band surgery
I was recently hospitalized for aspiration pneumonia. They thought it was related to the lap band, so they took it out. The GI doctor did and EGD and …
Stabbing pain to the side of my port 3 weeks after lap band surgery
I had my band fitted 3 weeks ago. I have been doing great until Thursday, when I developed a stabbing pain to the side of my port when I move or bend down. …
Morning sickness syndrome after weight loss surgery
The doctor said that morning sickness syndrome after weight loss surgery was very rare, but I have been in the hospital twice with it and am still suffering …
Heartburn and acid reflux after lap band surgery with no weight loss
I had the lap band surgery in 2005, and I haven't lost much weight. I have heartburn after drinking water and acid reflux so bad at night I can't sleep. …
Gastric Sleeve Surgery After Failed Lap Band Surgery
I had lap band surgery which worked great... I lost over 100 pounds (45 kg). But my band slipped (probably my over-stuffing) and it stopped working. …
Gurgling sounds in upper chest after gastric sleeve surgery
I had the gastric sleeve, and I notice that I have a gurgling in my upper chest. When I take a bite of pudding it hurts, and I noticed tonight that my …
Lap band erosion 18 months after surgery
Approx 18 month after my lap band operation I started to experience stomach pain and went for check up at the hospital. It was then found out the band …
All fluid in my lap band is gone
I have had the gastric band for five years. Today I went to the hospital to have a fill done to my band and the doctor (who was also x-raying my band …
RNY Gastric Bypass After Lap Band Surgery
I was banded March 2011. I have to admit I am disappointed in my choice. It is uncomfortable all over - I have problems swallowing and never am full. …
Side Effects of the Gastric Band (Part Three of Three) - But it’s not so bad...
Here I am again with the last of my three articles on the downside of having a gastric band ( click here to go back to part one ). Of course it’s …
Lap band flipped or moved after fill
What happens if your band flips or moves after you had a fill & you feel ill? Originally I was scheduled for gastric bypass. I lost 52 pounds in preparation …
Side effects of having a Gastric Band (Part One of Three): There’s good news and bad news…
In my family one of the most heated discussions, repeated on a regular basis, was whether pessimism and realism were the same thing. “Don’t be so pessimistic!” …
Can you lose so much weight that the port becomes too long?
I have lost 180 pounds since my band surgery 5 yrs ago. My port is sticking out about an inch right under my rib cage. It is VERY uncomfortable. I …
Lap band patient vomiting blood and stomach pain
My wife has had the lap band since approx. 2008. She has been in the hospital (2010) once for an ulcer and severe acid reflux (band way too tight). The …
Sometimes unable to keep down liquids after lap band surgery
I very often go days without being able to drink without it giving me pressure in my chest followed by me having to vomit. I have had my band adjusted …
Lap band surgery complications
Now three years after lap band surgery, I just had 3cc of fluid removed from my band today because I am considering removing the band. Now I taste a back …
Lack of energy after gastric bypass surgery
I had gastric bypass surgery, and not I sometimes lack energy. Do you have any suggestions for this? How about electrolyte supplementation? Thanks …
Post surgical "problems" Vertical Sleeve Gastrectomy/VSG
Bariatric Surgery is not something to been taken lightly. If you're not worried about complications, then you are certainly in a small, small minority. …
Is there a chance the REALIZE Band will be recalled because of complication rate?
I had the Realize band which has a higher rate of irritating the stomach - when mine is adjusted enough to work it irritates until it swells my esophagus …
Nicotine Test Before Weight Loss Surgery
I am scheduled to have gastric bypass weight loss surgery in mid-September. When I went for my consultation my doctor said that she was going to do a …
Food stays in my throat and espohagus after lap band surgery
Instead of my food moving down quickly it seems to take forever... it moves down a bit then back up a bit and then down and up many times in my esophagus. …
Band Slips w/ the Lap Band
I have had my lap band for over 3 yrs now . The day I hit my goal weight I slipped my band. You slip your lap band a few ways (or you can slip it …
Marginal Ulcers After Gastric Bypass
I have always considered myself one of those gastric bypass success stories. Weight loss was achieved with only a few minor issues. I was a huge proponent …
Stricture Plus Hosptial-Acquired Bacteria After Gastric Bypass Surgery
I had gastric bypass surgery Sept. 2007. At first, everything seemed fine. After one week, I could not keep anything down and went back to the hospital. …
Severe Side Pain, Diarrhea and Hard Stomach 7 Years After Lap Band Surgery
I had the lap band for about 7 years, I only lost 50 pounds and I threw up all the time. In April 2012 I had emergency surgery due to severe pain for …
Gastric Sleeve Complications: Leak, Stenosis and Kink in Sleeve
June 25, 2012 I underwent 5 1/2 hour surgery for a sleeve gastrectomy. The length of the surgery was due to extreme amount of scar tissue due to a previous …
Acid Reflux After Bariatric Surgery Turned Out to Be Hernia/Twisted Intestines
What I thought was acid reflux was actually an inverted hernia/twisted small intestine. Here's the story... A year after bariatric surgery I was experiencing …
Dumping Syndrome with the Gastric Sleeve
Dumping syndrome is something that is usually associated with the RnY gastric bypass procedure. But did you know that you can dump even if you haven't …
My first complication after Gastric Bypass
Like any other surgery, bariatric surgery has risks/side effects and complications. I had Roux-en-Y Gastric Bypass surgery on October 18, 2007 and my …
Weight Loss Surgery Medical Publications: Some things you can’t Google
Innovations in the medical world take a while to percolate through to the common woman/man, even if they’re being broadcast with screaming headlines by …
Side Effects of the Gastric Band (Part Two of Three) - What happens later on as you settle into the band
This is the second of three articles about the less starry-eyed side of having a gastric band. It’s a wonderful tool, but you should not be blind to the …
Research Your Bariatric Surgeon First!
First, this post is NOT against lap band surgery in general. Even though my banded experience was quite traumatic, I still don't regret it. Just wish …
For more about how patients who have had surgery feel about bariatric surgery complications, see our Life After Weight Loss Surgery page.
If you think you are experiencing any of the following bariatric surgery complications, play it safe and call your doctor.
Click on a letter below to jump to a bariatric surgery complication beginning with that letter or scroll down the page to review the complete list of complications, definitions30 and treatments...
Abdominal hernias - a protrusion of an organ or part through connective tissue or through a wall of the cavity in which it is normally enclosed - also called a "rupture". Most hernias are treated with surgery unless another condition makes surgery inadvisable.
Aches - see Body Aches.
Anastomotic Leaks happen when the surgical connection made during bariatric surgery leaks digestive contents into the abdomen. See Gastrointestinal Leaks for more.
Anesthesia complications - See General Anesthesia Complications.
Anemia - a condition in which the blood is deficient in red blood cells, in hemoglobin or in total volume. Anemia is a common issue stemming from vitamin deficiency after malabsorptive bariatric surgery procedures.
Anemia following bariatric surgery is routinely treated with iron orally and, when indicated, with intravenous iron infusions; blood transfusions are rarely required. Finding and treating anemia before surgery with iron and ESA therapy has been found to be effective at both avoiding transfusions and reducing surgery risks.6
- Band Erosion (also called "Band Migration") - occurs in gastric banding (lap band surgery) and vertical banded gastroplasty patients as these are the only bariatric procedures involving a band. Band erosion occurs when the band actually grows into the stomach. The only treatment is a permanent removal of the band. See our Lap Band Erosion page for more information.
- Band Intolerance - when patients do not respond well (i.e. excessive and continued vomiting) to the band placed during vertical banded gastroplasty or gastric banding (lap band) surgery. Will probably require that the band be permanently removed.
- Band leak (1.1% - 4.9% of lap band patients) - patients can usually tell if their lap band system has a leak if their feelings of restriction (how much they can eat) decrease over time without the doctor unfilling the port. To determine if you have a lap band leak, your doctor may inject colored fluid and take an X-Ray to see if any of the colored fluid is present (from a leak) outside of the lap band system. Surgery is usually required to repair it.
- Band Migration - See Band Erosion.
- Band Slippage - occurs when the lower part of the stomach "slips" up through the band, creating a bigger pouch above the band (only occurs after gastric lap band surgery and vertical banded gastroplasty as these are the only bariatric procedures involving a band). As many as 1 in 10 patients experience this with gastric banding (lap band surgery), and either removing fluid from the lap band or surgery is required to repair it. Symptoms include vomiting and reflux. It is diagnosed by drinking a dye and using X-Ray to observe it. For information about surgical techniques to reduce the risk of slippage, see our Gastric Lap Band Procedure page.
Bleeding - See Hemorrhage.
Blood Clots (also called "thrombus") - overweight people have a higher risk of developing blood clots during and after any kind of surgery. Blood thinners are usually administered during and after surgery to avoid them, along with special devices that squeeze the lower legs to keep the blood flowing. Walking around periodically after surgery is also very effective. Symptoms of blood clots include swelling or pain in the legs and can be diagnosed by your doctor with an ultrasound. If clots occur, they are treated by a taking a prescribed blood thinner. If left untreated, clots can lead to a pulmonary embolism. Prior to surgery, be sure to tell your doctor whether you or anyone in your family has a history of clotting. Smoking will increase your risk, so if you are a smoker it is recommended that you stop smoking as soon as possible before surgery - no later than two months out. For more information, see our Blood Clot Symptoms, Treatments & Prevention page.
Body Aches - should pass with time. If they become unbearable, talk with your doctor about which pain relievers are safe. You should typically avoid NSAIDs (non-steroidal anti-inflammatory drugs) such as ibuprofen or Aleve.
- Feeling cold - this is caused by both your changed metabolism and weight loss and the fact that you have less fat insulating your body.
- Weak or tired feeling - should pass with time, especially once your new bariatric diet is in place and, as soon as you are feeling up to it, your weight loss surgery exercise program has begun.
- Diarrhea or loose stools (especially after gastric sleeve surgery, duodenal switch, gastric bypass surgery and mini gastric bypass surgery) - usually completely dependent on diet - you will need to figure out and avoid foods that "trigger" diarrhea. Could also be the result of lactose intolerance which would require dairy products to be removed from your bariatric diet.
- Constipation (especially after gastric banding (lap band surgery), gastric bypass, mini gastric bypass and rarely after duodenal switch) - usually fixed by increasing the amount of water you are drinking and taking fiber supplements such as Fiber-Stat's liquid fiber supplement (aff).
- Foul-smelling bowel movements & flatulence (especially after duodenal switch) - as with diarrhea, it is usually dependent upon diet.
- Difficulty swallowing ("dysphagia") (after all restrictive procedures) - caused by eating too quickly, too much or not chewing food enough and can usually be fixed by avoiding these issues. (See our Bariatric Eating page to learn about proper eating techniques that will avoid problems.)
- Gurgling Noises - not necessarily uncomfortable or dangerous, but it's worth noting. Gurgling noises are completely normal and are due to air in the stomach and the different way that your new digestive system pushes the air through. The best way to avoid gurgling noises is to avoid swallowing air (i.e. avoid carbonated beverages, sipping through a straw, eating or drinking too quickly and chewing gum).
Bowel Obstruction - also called an "internal hernia", is a lifelong risk following bariatric surgery that occurs when the intestines twist and prevent the flow of food and digestive fluids. Patients with this condition usually experience abdominal pain, abdominal swelling or vomiting. A doctor will confirm the diagnosis with a CAT scan or through surgery, and surgery may or may not be needed to treat it.
Bowel obstructions post-surgery are more commonly associated with adhesions and not internal hernias, although both are known to be associated with post-op bowel obstructions.
Bowel Perforation - See Organ Injury During Surgery.
Cold feeling - See Body Feeling Changes.
Death - the bariatric surgery mortality rate is extremely low at about 0.135% and has continued to drop over time.5 For a boiled down list of issues that directly contribute to mortality risk, see our Bariatric Surgery Risks page.
Deep vein thrombosis (DVT) is a risk after any surgery (bariatric or otherwise) marked by the formation of a thrombus within a deep vein (as of the leg or pelvis) that may be asymptomatic or accompanied by symptoms (such as swelling and pain). DVT is potentially life-threatening if dislodgement of the thrombus results in pulmonary embolism . Preventive measures are extremely important, especially for those with a history of blood clotting problems. Blood thinners and compression stockings help to reduce the risks. Also see Blood Clots.
Dehydration - an abnormal depletion of body fluids. You will need to drink a significant amount of water in the months following surgery - as much as 2 liters per day. Not doing so can lead to nausea and vomiting which can cause even worse dehydration and other problems. In severe cases of dehydration patients must return to the hospital for IV fluids and vitamins.
Dyspepsia (also called indigestion) - inability to digest or difficulty in digesting food; incomplete or imperfect digestion of food; a case or attack of indigestion marked especially by a burning sensation or discomfort in the upper abdomen. Treatment is usually as simple as changing your diet, such as avoiding greasy foods or only drinking liquids for a certain period of time. Alcohol, aspirin and other drugs are also causes. If diet changes don't work, antacids and H2 blockers are sometimes prescribed.
Dysphagia (difficulty swallowing) - See Bowel Function Changes.
Dumping syndrome - we have an entire page dedicated to this topic, but in general it's a condition characterized by weakness, dizziness, flushing and warmth, nausea and palpitation immediately or shortly after eating. It is produced by abnormally rapid emptying of the stomach especially in individuals who have had part of the stomach removed. See our Dumping Syndrome page for more.
Embolism - See Pulmonary Embolism.
Esophagitis - occurring in less than 1% of patients, esophagitis is the inflammation of the esophagus. It is usually treated non-surgically by making the patient comfortable through a change in diet (avoiding fats and chocolate) and/or avoiding/prescribing certain drugs.
Esophageal dilation - is the enlarging of the esophagus (the opening, not necessarily inflammation) and is usually the result of a restrictive procedure. Most cases can be handled through deflation of the band under radiological control.8 GERD symptoms and vomiting are more frequent in patients who develop esophageal dilation.9
Evisceration & Incisional hernia - occur when an internal organ or body part protrudes through a surgical incision. More likely to occur with open procedures than with laparoscopic procedures and usually occurs months after surgery. These are typically repaired with surgery.
Fistulas - see Gastric Fistula.
Food trapping - when food gets caught in one of the small openings in your digestive system. Seen in 1 to 2% of lap band patients and treated by deflating the band entirely until the food passes through.10,11
Gallstones - small stones of cholesterol formed in the gall bladder or bile passages. Gallstones can be created following rapid weight loss which leads to their development in as many as 1/3 of bariatric surgery patients. As a result, your surgeon may remove your gallbladder during surgery or prescribe bile salt supplements after surgery.
Gastric fistula - occurring in up to 4% of bariatric surgery patients, a gastric fistula is an abnormal passage that leads from an abscess or hollow organ or part to the body surface or from one hollow organ or part to another.12 Sepsis can follow, and surgery is usually required to fix it.
Gastric fistulas are associated with the stomach (i.e. 'gastric'). However, not all fistulas are associated with the stomach, and other types can occur (such as from an intestine to intestine anastomosis.)
Related risk/complication of gastric fistula: Wound Sepsis
Gastritis - inflammation, especially of the mucous membrane of the stomach. Symptoms include bloating, excessive belching, a burning sensation in the stomach, loss of appetite, nausea and vomiting. Eating better may get rid of the problem, or your doctor may prescribe antacids or other over the counter medications.
Gastroesophageal reflux disease (GERD) - a highly variable chronic condition that is characterized by periodic episodes of gastroesophageal reflux and usually accompanied by heartburn. It may result in histopathologic changes (change in the microscopic structure) in the esophagus. It also often leads to esophagitis. GERD increases the risk of some bariatric surgery complications such as dumping syndrome and sepsis, but the condition is also improved for many following bariatric surgery.2,13 Several at-home treatments are effective, including avoiding certain foods and drinks (alcohol, citrus juice, tomato-based food and chocolate), waiting 3 hours before lying down after a meal, eating smaller meals and elevating your head 8 inches when you lay down. If these don't work, your doctor may recommend/prescribe antacids, H2 blockers or even Proton Pump Inhibitors (PPI). See our Gastroesophageal Reflux Disease Symptoms and Treatments page (coming soon) for more details.
Gastrointestinal leaks (including staple line leaks) occur when sealed or sutured (stitched) openings leak digestive contents into the abdomen. This can cause infection and abscess. Gastrointestinal leaks occur in as many as 5% of patients and can be repaired as long as it is caught early. Symptoms include fever, severe pain and a high heart rate. In order to prevent leaks, your surgeon should check the surgical connections a number of different ways, including (1) blowing air into the connection and observing whether any gets through and (2) using a dye to check for a leak. Leaks not discovered right away are usually treated by resting the stomach (being fed through an IV), but sometimes surgery is required to fix them.
General anesthesia complications - anesthesia risks increase with age and body mass index (BMI). Other health issues can also increase your risk, including circulatory or respiratory problems. However, anesthesia complications are usually minor and are relatively easy for your doctors to handle.
Hair loss - this can be an alarming side effect of rapid weight loss, but it is only temporary. It happens in about half of all patients in the year following surgery. Proper nutrition is the best defense, including protein and the right bariatric vitamins. Several other treatments can also help, including the application of special shampoos and oils (i.e. Nioxin shampoo, flax seed oil, biotin tablets or powder).
Heart attack (also called myocardial infarction) - an acute episode of heart disease marked by the death or damage of heart muscle due to insufficient blood supply, usually as a result of a coronary thrombosis or a coronary occlusion. Heart attacks are especially characterized by chest pain. The chances of having a heart attack during surgery are less than 0.5%.14
Hemorrhage (bleeding) - a copious discharge of blood from the blood vessels. One study showed that out of 1,700 laparoscopic bariatric surgery patients only 3 had hemorrhagic complications, none of which needed to be converted to open operations or needed reoperations.15 However, other studies have shown internal bleeding to be as high as 4% following Roux-en-Y gastric bypass surgery. After the surgeon determines the type and severity of internal bleeding, it can be resolved in a number of ways: on its own, replenishing bodily fluids, stopping the use of all anticoagulation drugs and (rarely) by transfusion or reoperation.16
Hernia - See Evisceration.
Hiatal Hernia - a hernia in which an anatomical part (such as the stomach) protrudes through the esophageal hiatus of the diaphragm. Hiatal hernias can occur after restrictive procedures when food causes the smaller stomach to bulge and push through the diaphragm. It is also not uncommon for an obese patient to already have a hiatal hernia before surgery. While it can be a "contraindication" for surgery (reason that you may not be able to have the surgery), hiatal hernias can also be repaired during bariatric surgery.17
Hypoglycemia - Low blood sugar related to excessive insulin production. As a bariatric surgery complication, hypoglycemia is often the result of excessive dumping following Roux-en-Y gastric bypass surgery.18,19 Medications can usually help mild to moderate conditions, however surgical removal of part or all of the pancreas (which produces insulin) may be required for more serious cases. Symptoms following surgery include rapid heart rate, shaking, sweating, confusion, feeling lightheaded, bad headaches or feeling overly hungry.
Incision(al) hernia - See Evisceration.
Indigestion - See Dyspepsia.
Infection - to contaminate with a disease-producing substance or agent (such as bacteria). Much more common in open surgeries than in laparoscopic surgeries due to the size of the external incisions. Usually treated with antibiotics.
Intolerance to certain foods - With a changed stomach size or digestive system, there will be certain foods that you'll need to avoid and certain diet habits you'll need to maintain. See our Bariatric Diet section for more. Also see Bowel Function Changes.
Kidney stones - stones in the kidney related to decreased urine volume or increased excretion of stone-forming components such as calcium, oxalate, urate, cystine, xanthine and phosphate. The stones form in the urine collecting area (the pelvis) of the kidney and may range in size from tiny to staghorn stones the size of the renal pelvis itself.20 Although additional research is needed, one study suggested that the risk of developing kidney stones increases after bariatric surgery due to changes in digestion and the resulting changes in the chemical makeup of patients' urine. Click here to learn more.
Leaks - See Gastrointestinal Leak.
Malnutrition/Malabsorption - See Vitamin Deficiency.
Marginal Ulcers - Marginal ulcers are relatively common after Roux-en-Y gastric bypass, mini gastric bypass, and duodenal switch (Scopinaro procedure), and are the most common in the newly created stomach pouch after Roux-en-Y gastric bypass surgery.
Ulcers can usually be avoided by an appropriate bariatric diet, by not smoking and by staying away from NSAIDs (non-steroidal anti inflammatory drugs, including ibuprofen, Aleve, etc.). You can often tell if you have one because of a burning pain in the stomach. Your doctor can confirm ulcers with an endoscopy (a scope than is inserted through your mouth and down your esophagus) and usually treat them with antacids.
Nausea and vomiting are one of the most common side effects of bariatric surgery and are experienced in up to 70% of patients. In one study, patients reported feeling nauseous 1.4 times per week on average after gastric banding (lap band surgery) and 2.6 times per week after gastric bypass surgery.21 They also reported vomiting 0.9 times per week on average with the band and 0.2 times per week after gastric bypass. Following the doctor's orders regarding your bariatric diet will typically fix or improve the problem. While in the hospital, receiving a larger amount of IV fluids at a faster rate may make you less likely to feel nauseous or vomit.22
Organ injury during surgery - Caused by surgeon error during surgery. Injuries to your internal organs during surgery are a possibility, especially the bowel, stomach, spleen or esophagus due to their close proximity to the stomach/intestines.
Peritonitis - inflammation of the peritoneum (the smooth transparent serous membrane that lines the cavity of the abdomen, is folded inward over the abdominal and pelvic viscera, and consists of an outer layer closely adherent to the walls of the abdomen and an inner layer that folds to invest the viscera). Peritonitis after bariatric surgery is a serious complication that is usually caused by a gastrointestinal leak. Surgery is required to fix it.23
Pneumonia - a disease of the lungs that is characterized especially by inflammation and consolidation of lung tissue followed by resolution. It is accompanied by fever, chills, cough, and difficulty breathing, and is caused chiefly by infection. Obese patients are more likely to develop pneumonia post-surgery, so it is important that patients begin deep breathing and coughing exercises following surgery to prevent it. These exercises are much easier after laparoscopic surgery than after open surgery. Should pneumonia develop, it can be treated with antibiotics.
- Port flip/inversion or dislodgement (10.3% of patients) - occurs when the lap band port (where fluids are taken out or added to the band) "flips over". This is typically not a serious problem and a quick surgical procedure can turn it back over.
- Port Leak (1.1% - 4.9% of patients) - as with a band leak, patients can usually tell if their lap band system has a leak if their feelings of restriction decreases (i.e. the amount they can eat increases) over time without the doctor unfilling the port. To determine if you have a port leak, your doctor may inject colored fluid and take an X-Ray to see if any of the colored fluid is present (from a leak) outside of the lap band system. Surgery is usually required to repair it.
- Port or band infection (1.5% - 5.3% of patients) - if port or band infection occurs, it is usually healed with antibiotics, but removal of the band or port may be necessary.
- Port dislocation (6.9% of patients) - similar to a port flip, a port dislocation means that your port has moved from its original location. It can be fixed with a simple operation under local anesthesia.
Postoperative bleeding - refers to internal bleeding following bariatric surgery. See Hemmorhage.
Pouch dilation - refers to the enlarging of the pouch created after certain types of surgery. For lap band surgery patients, it may be fixed by removing fluid from the band. For all procedures with a pouch, surgery is sometimes required to tighten it.25
Pulmonary embolism - embolism (the sudden obstruction of a blood vessel by an abnormal particle, such as a bubble, circulating in the blood) of a pulmonary artery or one of its branches that is produced by foreign matter (most often a blood clot originating in a vein of the leg or pelvis) that is marked by labored breathing, chest pain, fainting, rapid heart rate, cyanosis, shock, and sometimes death. Also see Blood Clots and Deep Vein Thrombosis.
Respiratory failure is a rare but serious complication.26 It occurs when oxygen and carbon dioxide levels fall too far outside of their normal ranges. Hospital treatment includes drugs and ventilation, among other techniques.
Sepsis - See Wound Sepsis.
Skin Changes such as acne or dry skin occur with some patients. The right bariatric diet and bariatric vitamins are your best defense. There are also many over the counter creams and lotions that can help. Worst case, partner with your dermatologist to find a treatment that works.
Spleen damage - See Organ Injury During Surgery.
Staple line leak - See Gastrointestinal Leak.
Stoma obstruction - a partial or complete blockage of the new or altered digestive opening created during bariatric surgery. See Food Trapping.
Stenosis/Stricture - a narrowing or constriction of the diameter of a bodily passage or orifice. This is most common in procedures that rearrange your digestive system such as gastric bypass surgery (up to 8% of patients) and duodenal switch surgery and results from a build-up of scar tissue between your intestine and your reduced stomach or at an intestine-to-intestine connection (anastomosis).
The primary symptom is almost always vomiting, and it is usually treated by inserting and inflating a balloon to stretch the connection between the stomach and intestine. GERD and older age increase the risk of strictures.27
Stroke - sudden diminution or loss of consciousness, sensation and voluntary motion caused by rupture or obstruction (as by a blood clot) of a blood vessel of the brain. Obese patients have a higher general risk of stroke, and bariatric surgery has been shown to reduce the risk.28
Thrombus - See Blood Clots.
Thrombophlebitis - inflammation of a vein with formation of a thrombus (a clot of blood formed within a blood vessel and remaining attached to its place of origin). The body's response could be to produce more clots which increase the risk of Deep Vein Thrombosis and Pulmonary Embolism. Also see Blood Clots.
Tired feeling - See Body Feeling Changes.
Thrush (yeast infection) - this can be a side effect of the antibiotics you are on to prevent infection immediately following surgery. Symptoms include changes to your tongue such as a white coating, redness or inflammation. This is easily cured with medicine, so let your doctor know if this starts to develop.
Ulcers - See Marginal Ulcers.
Vitamin and mineral deficiency / malnutrition / malabsorption - symptoms include fatigue, anemia and osteoporosis and are usually completely avoided by strictly following your doctor's prescribed vitamin and supplement regimen. You should also have blood work at least semi-annually to make sure that you continue to receive the proper amounts. (see our Bariatric Vitamins page for the problems associated with vitamin deficiency)
Vomiting - See Nausea and Vomiting.
Weak feeling - See Body Feeling Changes.
Weight regain - Most bariatric surgery patients will experience some weight regain after the lowest weight level is reached. See our Weight Gain after Bariatric Surgery page for more.
Wound infection - See Infection.
Wound sepsis (and sepsis in general)- a systemic response typically to a serious localized infection (as of the abdomen or lungs) especially of bacterial origin that is usually marked by abnormal body temperature and white blood cell count, tachycardia and tachypnea; specifically: a systemic inflammatory response syndrome induced by a documented infection.
While wound sepsis can occur from any source of infection, this serious complication often results from a gastric fistula. Due to the risk of wound sepsis following a gastric fistula, the fistula must be treated immediately and effectively in order to avoid sepsis.29 If sepsis does develop, patients are often treated in the intensive care unit with IV fluids and antibiotics.
Yeast infection - See Thrush.
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References for Bariatric Surgery Complications Page
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- MedicineNet.com. Definition of a Kidney Stone. Available at: http://www.medterms.com/script/main/art.asp?articlekey=6650. Accessed: September 19, 2009.
- Niccole Siegel, MS, RD, Barrie Wolfe, MS, RD, Giovanni Dugay, NP, Christine J. Ren, MD. REPORTED INCIDENCE OF VARIOUS POST OPERATIVE EXPERIENCES ASSOCIATED WITH THE LRYGB, LAGB AND LBPD/DS. New York University Program for Surgical Weight Loss, New York, NY, USA. June 2004. Abstracts of the 21st Annual Meeting - American Society for Bariatric Surgery.
- Schuster R, et al. Intra-operative Fluid Volume Influences Postoperative Nausea and Vomiting after Laparoscopic Gastric Bypass Surgery. Journal Obesity Surgery Volume 16, Number 7 / July, 2006 Pages 848-851.
- Ettinger, et al. Closure of the Abdominal Cavity after Severe Peritonitis in Bariatric Surgery Utilizing a Mesh and Plastic Device. Journal Obesity Surgery. Volume 15, Number 9 / October, 2005 Pages 1336-1340.
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[Last editorial review/modification of this page : 10/9/2013]