Bariatric surgery, like any surgical procedure, comes with its own set of risks and potential complications. Understanding them is an important part of making an informed decision. In this guide, we’ll walk you through the general risks of weight-loss surgery as well as the specific ones linked to the gastric sleeve and gastric bypass to help you feel informed, confident, and prepared before taking your next step.
Why People Choose Bariatric Surgery
People turn to weight loss surgery for reasons that often go beyond the number on the scale. It’s typically considered for those with a high Body Mass Index (BMI) who have not found success with diet and exercise alone, especially when they have serious obesity-related health conditions.
The goal is to use a surgical tool to help achieve significant weight loss, which can lead to:
- Remission of type 2 diabetes, improvement of high blood pressure and sleep apnea.
- Reduced strain on joints, alleviating chronic pain.
- Improved mobility and quality of life.
- Enhanced self-esteem and mental well-being.
Understanding these profound benefits helps frame why individuals are willing to accept and manage the associated bariatric surgery risks.
Risks During Bariatric Surgery
While bariatric surgery is generally safe, it is major surgery, and certain risks are inherent to any procedure involving anaesthesia and abdominal operations. These include, but are not limited to:
- Reactions to anaesthesia
- Excessive bleeding (haemorrhage)
- Blood clots in the legs (deep vein thrombosis) that can travel to the lungs (pulmonary embolism)
- Breathing or heart problems
- Inadvertent injury to surrounding organs, such as the spleen, liver, or oesophagus
Your surgical team is trained to monitor and manage these issues throughout the procedure to keep you safe.
Early Post-Op Risks After Bariatric Surgery
The first few weeks after surgery are a critical healing period. The most common early post-op bariatric surgery complications can include:
Leaks: This is one of the most serious complications, where the new connections or staple lines inside the abdomen leak digestive fluids. It requires immediate medical attention.
Infections: This can occur at the incision sites (wound infection) or inside the abdomen.
Bleeding: Some internal bleeding may occur after surgery.
Bowel Obstruction: A blockage in the intestine can be caused by scar tissue or an internal hernia.
Dehydration and Malnutrition: Difficulty eating and drinking can quickly lead to these issues if not carefully managed.
Acid Reflux (GERD): Some patients experience new or worsened acid reflux as the stomach’s new shape can affect its valve function.
Esophageal Dilation: In some cases, the esophagus (food pipe) can widen over time if there’s a stricture or obstruction, leading to swallowing difficulties.
Long-Term Risks of Weight Loss Surgery
Life after surgery requires lifelong commitment and monitoring. Some long-term risks of weight loss surgery can develop months or years later. These complications often relate to the body’s altered ability to absorb nutrients and changes in anatomy:
Nutritional Deficiencies: Deficiencies in iron, calcium, vitamin B12, and other vitamins are common and can lead to anaemia or osteoporosis if not managed with lifelong supplementation.
Dumping Syndrome: This occurs when food moves too quickly from the stomach into the small intestine, causing nausea, cramping, diarrhoea, and dizziness.
Gallstones: Rapid weight loss increases the risk of developing gallstones, which are hardened deposits of digestive fluid that can form in your gallbladder
Hernias: The incisions in the abdominal wall can weaken, allowing tissue to protrude.
Ulcers: Sores can develop in the stomach or small intestine.
Weight Regain: Without adherence to dietary and lifestyle guidelines, it is possible to regain some weight over time.
Weight Loss Surgery Complications per Procedure
Different procedures have different risk profiles. Here’s a breakdown of the most common bariatric surgery complications associated with the two primary techniques.
Gastric Sleeve Risks and Complications
The gastric sleeve procedure involves removing a large portion of the stomach. Its specific risks include:
Leakage: This is one of the most serious complications, occurring from the long staple line.
Stricture: A narrowing of the sleeve tube can cause an obstruction, making swallowing difficult.
Chronic Acid Reflux or Heartburn: The new stomach shape can impair the valve that prevents acid from flowing back up.
Blood Clots: As with any major surgery, there is a risk of deep vein thrombosis (DVT) or pulmonary embolism (PE).
Gallstones: The risk increases with rapid weight loss after surgery.
Hernia: This can occur at an incision site or internally.
Internal Bleeding: This can happen from the staple line or other surgical sites.
Perforation of Stomach or Intestines: An accidental tear in the stomach or intestinal wall.
Skin Separation: Wound healing issues can lead to separation at the incision sites.
Vitamin or Iron Deficiency: Long-term nutritional deficiencies are common and require lifelong supplementation and monitoring.
Gastric Bypass Risks and Complications
Gastric bypass is a more complex procedure that creates a small stomach pouch and reroutes the small intestine. Its specific risks include:
Internal Bleeding: Can occur from the staple lines or surgical sites.
Bowel Obstruction: This can be caused by internal hernias, adhesions, or at the connection site (pouch/anastomotic obstruction).
Leakage: This is a serious complication that can occur at the new connections (anastomoses) between the stomach and intestine.
Stricture: A narrowing can develop at these connections, causing difficulty swallowing and obstruction.
Gallstones: The risk increases significantly with rapid post-operative weight loss.
Nutritional Deficiencies: The procedure is malabsorptive, leading to high risks of vitamin or iron deficiency and protein or calorie malnutrition if supplements and diet are not strictly followed.
Staple Line Breakage: Failure of the staples used to create the stomach pouch and intestine connections.
Dumping Syndrome: A common side effect where food moves too quickly into the small intestine, causing nausea, cramping, and diarrhea.
Hernias: Can occur at incision sites or internally where the intestine was rerouted.
Marginal Ulcers: Sores (ulceration) can develop at the connection between the stomach and intestine.
Spleen or Other Organ Injury: Rare, but possible during surgery due to the close proximity of organs.
Perforation: An accidental tear in the stomach or intestines.
Pulmonary and/or Cardiac Problems: Such as pneumonia, blood clots (pulmonary embolism), or heart-related issues linked to major surgery.Skin Separation: Issues with wound healing at the incision sites.
Common Side Effects After Weight Loss Surgery
It’s important to distinguish between complications and side effects. Side effects of weight loss surgery are common, expected, and often temporary parts of the recovery and adaptation process. These side effects can include:
- Hair thinning or loss for several months due to rapid weight loss and physiological stress.
- Food intolerance, where certain foods (like red meat, bread, or dry foods) may cause nausea or vomiting.
- Body aches and feeling cold more often as your metabolism changes.
- Changes in bowel habits, such as constipation or diarrhoea.
- Fatigue and low energy, especially as your body adjusts to a very low-calorie diet.
How to Reduce the Risks Of Bariatric Surgery
You play the most critical role in minimising your bariatric surgery risks. Key steps include:
- Choose an accredited hospital and an experienced surgeon. Discover why having surgery in Ireland is a safer choice than going abroad.
- Attend All Pre-operative Appointments and follow all instructions to optimise your health before surgery.
- Be Transparent about your full medical history and any medications you take.
- Commit to Lifelong Follow-up Care, including regular check-ups and blood tests.
- Adhere Strictly to Your Post-Op Diet and Supplement Plan.
- Follow your medical team’s advice and add appropriate physical activity after surgery.
- Seek support from support groups or a mental health professional to navigate the emotional journey.
- Quit Smoking
When You Should Contact Your Surgeon
Knowing the warning signs can prevent a minor issue from becoming a major problem. Contact your surgical team immediately if you experience:
- Fever above 38°C or chills.
- Increased redness, swelling, pain, or pus from an incision.
- Severe abdominal pain that doesn’t subside.
- Persistent nausea or vomiting (especially if you cannot keep down liquids).
- Chest pain, shortness of breath, or a rapid heart rate.
- Pain, redness, or swelling in your calf or leg.
- No bowel movements for three days.
Frequently Asked Questions (FAQs)
The most common complications after bariatric surgery are nutritional deficiencies and digestive issues such as nausea, vomiting, or acid reflux. These are usually managed with dietary guidance and vitamin supplementation. Serious complications like leaks or blood clots are rare when surgery is performed by an experienced bariatric team.
Modern bariatric surgery is considered very safe, with complication rates comparable to common procedures like gallbladder removal. When performed by experienced surgeons and followed by proper aftercare, the risks are low and the long-term health benefits, such as improved diabetes, heart health, and mobility, greatly outweigh the potential risks.
Ten years after surgery, most patients maintain significant weight loss and continue to experience improvements in conditions like high blood pressure and sleep apnoea. However, long-term success depends on maintaining healthy eating habits, regular exercise, and attending follow-up appointments.
Bariatric surgery primarily affects the stomach and, in some procedures, the small intestine. The stomach is reduced in size or bypassed to limit food intake and absorption. These changes influence how your digestive system processes nutrients, which is why ongoing vitamin and mineral supplementation is essential after surgery.
Both the gastric sleeve and gastric bypass are safe and effective when performed by an experienced surgeon. The sleeve tends to have a slightly lower risk of complications because it’s less complex and doesn’t reroute the intestines. However, gastric bypass can offer better long-term results for patients with severe obesity or diabetes. Your surgeon will help determine the safest and most effective option for your needs.
One of the main side effects that can occur after bariatric surgery is malnutrition, caused by changes in how your body absorbs nutrients. This can result in low blood sugar (hypoglycaemia), vitamin and mineral deficiencies, or dumping syndrome, where food passes too quickly into the intestines, leading to nausea, weakness, or dizziness after meals.
Less frequent but more serious complications may include bowel blockages, hernias, gallstones, or stomach ulcers. Following your surgeon’s aftercare plan, taking prescribed supplements, and attending regular check-ups greatly reduce the likelihood of these problems.
Considering Bariatric Surgery?
Embarking on the path to bariatric surgery is a journey that requires courage, information, and a strong partnership with your medical team. While the list of potential weight loss surgery complications can seem daunting, it’s important to remember that for the vast majority are not the norm.
If you are considering this life-changing step in Ireland, the most important thing you can do is seek a thorough consultation. Our expert team will assess your individual health profile, explain your personal risk-benefit ratio, and guide you toward the best fitted path for you.
