Most people recover from bariatric surgery without serious problems. But complications do happen, and the difference between a minor issue and a major one is often how fast you act. This page covers the warning signs that require immediate medical attention. If you have one of these symptoms, do not wait. Call your surgeon or go to the emergency room.
Some discomfort is normal after surgery. Soreness at the incision sites, fatigue, and mild nausea are expected. But the symptoms below are not part of normal recovery.
Quick Reference: Symptom, What It May Mean, What to Do
Use this table to check your symptoms. If you are unsure, err on the side of calling your care team. They would rather hear from you than have you wait.
| Symptom | What It May Mean | What to Do |
|---|---|---|
| Severe abdominal pain that does not improve or gets worse | Gastric leak, internal bleeding, obstruction | Stop eating and drinking. Call your surgeon immediately. Go to the ER if pain is severe or you cannot reach your surgeon. |
| Fever over 100.4 degrees Fahrenheit with chills or sweats | Infection at incision site, inside the abdomen, or in the lungs | Call your surgeon. You may need antibiotics or imaging. |
| Heart rate above 100 beats per minute at rest | Dehydration, infection, bleeding, or pulmonary embolism | Check for other symptoms. Call your surgeon. Go to the ER if you also have shortness of breath or chest pain. |
| Shortness of breath or trouble breathing | Pulmonary embolism, pneumonia, or fluid in the lungs | This is a medical emergency. Go to the ER or call 911. |
| Chest pain or pressure | Pulmonary embolism, heart attack, or lung issue | Go to the ER or call 911 immediately. |
| Vomiting that does not stop or inability to keep fluids down | Dehydration, stricture, obstruction, or gastric leak | Stop eating. Sip small amounts of water. Call your surgeon if you cannot keep fluids down for more than 4 hours. |
| Pain or swelling in one leg, especially the calf or thigh | Deep vein thrombosis (blood clot) | Do not massage the leg. Call your surgeon. Go to the ER if the leg is swollen, warm, or painful. |
| Redness, warmth, swelling, or drainage at incision site | Wound infection | Keep the area clean and dry. Call your surgeon. You may need antibiotics. |
| Dizziness, fainting, or feeling lightheaded when standing | Dehydration, internal bleeding, or low blood pressure | Sit or lie down. Call your surgeon. Go to the ER if you fainted or feel like you will faint. |
| Dark urine, dry mouth, or urinating less than usual | Dehydration | Sip water slowly. Call your surgeon if symptoms do not improve within a few hours. |
| Black, tarry stools or blood in vomit | Internal bleeding or ulcer | Go to the ER immediately. Do not eat or drink anything. |
| Inability to swallow or food getting stuck | Stricture, obstruction, or swelling at the connection site | Stop eating. Try sipping warm liquids. Call your surgeon if it does not pass. |
| Confusion, difficulty waking up, or acting disoriented | Severe dehydration, infection, low blood sugar, or sepsis | Go to the ER immediately. This is a medical emergency. |
Gastric Leak
A gastric leak is one of the most serious complications after bariatric surgery. It happens when the staple line or surgical connection fails and stomach contents leak into the abdominal cavity. This can cause peritonitis, a life threatening infection. Leaks are rare but they require emergency surgery.
Signs of a gastric leak:
- Severe abdominal pain that gets worse, not better, over time
- Pain that radiates to the left shoulder or back
- Fever and chills
- Rapid heart rate (tachycardia)
- Nausea and vomiting
- Shortness of breath
- Confusion or feeling generally unwell
What to do: If you suspect a leak, stop eating and drinking immediately. Call your surgeon or go to the ER. A leak will not get better on its own. It requires surgical repair and antibiotics. Leaks are most common in the first few days after surgery but can occur up to several weeks later. Your surgeon will check for leaks before you leave the hospital, but you should still watch for these signs at home.
Pulmonary Embolism (PE)
A pulmonary embolism is a blood clot that travels to your lungs. It is a medical emergency. The risk is highest in the first two weeks after surgery but remains elevated for several months.
Signs of a pulmonary embolism:
- Sudden shortness of breath
- Chest pain that gets worse when you breathe deeply or cough
- Rapid heart rate
- Feeling lightheaded or passing out
What to do: Call 911 or go to the ER immediately. Do not drive yourself. A PE can be fatal within hours if not treated.
To reduce your risk of blood clots, walk as soon as you are able after surgery. Wear compression stockings if your surgeon recommends them. Do not sit still for long periods. Take your blood thinner medication as prescribed. If you are traveling soon after surgery, stop every hour to walk around.
Tachycardia
Tachycardia means a resting heart rate above 100 beats per minute. After bariatric surgery, a fast heart rate is often the first sign that something is wrong. It can appear before pain or fever develops.
Possible causes of tachycardia after bariatric surgery:
- Dehydration. This is the most common cause. Your body needs more fluids than you think.
- Internal bleeding. A drop in blood volume makes the heart beat faster to compensate.
- Infection or sepsis. The body speeds up the heart rate to fight an infection.
- Pulmonary embolism. A clot in the lungs strains the heart.
- Gastric leak. Inflammation from a leak stresses the entire body.
What to do: Check your pulse at rest. If it is above 100 and you have not been active, do not ignore it. Check for other symptoms like pain, fever, or shortness of breath. Call your surgeon. A fast heart rate with no other symptoms can still be the first sign of a serious problem.
Bowel Obstruction
Bowel obstruction happens when something blocks the passage of food or fluid through your intestines. After bariatric surgery, this can happen at the surgical connection site or in the small intestine. Internal hernias are a specific risk after gastric bypass.
Signs of bowel obstruction:
- Cramping abdominal pain that comes in waves
- Vomiting, especially after eating
- Inability to pass gas or have a bowel movement
- Bloating or visible swelling of the abdomen
- Nausea that does not go away
What to do: Stop eating and drinking. Call your surgeon. If you are vomiting and cannot keep anything down, go to the ER. A bowel obstruction that is not treated can lead to tissue death and perforation.
Dehydration
Dehydration is one of the most common reasons patients are readmitted to the hospital after bariatric surgery. You cannot drink large amounts at once after surgery, and many people struggle to get enough fluids. If dehydration is not treated, it can lead to kidney damage, electrolyte imbalances, and serious complications.
Signs of dehydration:
- Dark yellow urine or urinating less than 3 times per day
- Dry mouth and lips
- Dizziness when standing up
- Headache
- Fatigue that feels worse than expected
- Rapid heart rate
- Constipation
What to do: Sip small amounts of water or sugar free electrolyte drink throughout the day. Aim for 48 to 64 ounces of total fluid per day, but work up to that gradually. If you cannot keep fluids down, call your surgeon. You may need IV fluids to prevent serious complications.
For more on staying hydrated, see the Hydration After Bariatric Surgery page.
Infection
Infections can happen at the incision site or inside the abdomen. A small amount of redness around the incision is normal, but spreading redness, drainage, or warmth is not.
Signs of infection:
- Fever over 100.4 degrees Fahrenheit
- Chills or shaking
- Redness that spreads beyond the immediate incision area
- Warmth around the incision
- Yellow, green, or foul smelling drainage
- Increasing pain at the incision site after the first few days
- Feeling like you have the flu
What to do: Call your surgeon. You may need antibiotics. If you have a fever and abdominal pain that is getting worse, go to the ER. Internal infections can progress to sepsis quickly.
Internal Bleeding
Internal bleeding after bariatric surgery is rare but serious. It can happen at the staple line, the surgical connection, or the spleen.
Signs of internal bleeding:
- Rapid heart rate
- Low blood pressure or dizziness
- Pale skin
- Black, tarry stools
- Blood in vomit (looks like coffee grounds)
- Severe abdominal pain that gets worse
- Feeling weak or faint
What to do: Go to the ER immediately. Do not eat or drink. Internal bleeding requires emergency treatment.
When to Talk to Your Care Team
You should call your surgeon or care team any time you are unsure about a symptom. Do not worry about bothering them. They would rather hear from you early. Call if you have:
- Any of the symptoms listed in the table above
- A fever that does not go away
- Pain that is getting worse instead of better
- Vomiting that lasts more than a few hours
- Signs of dehydration that do not improve with sipping fluids
- A feeling that something is wrong, even if you cannot name it
Your surgeon's office should have a 24 hour phone number or an on-call service. Use it. When you call, tell them what symptoms you have, when they started, and what you have tried so far. If you cannot reach your surgeon and your symptoms are severe, go to the emergency room. Know the fastest route to the nearest ER before you need it. If you are having trouble breathing, chest pain, or signs of a PE, call 911. Do not drive yourself.
Related Reading
- Common Side Effects and How to Manage Them What is normal and what is not during recovery.
- Hydration After Bariatric Surgery How to prevent dehydration and meet your fluid goals.
- Signs of Complications and When to Call Your Doctor A companion page for post-op complication awareness.
- What to Expect in the First Year Recovery milestones and what is normal at each stage.
- Post-Op Diet Stages Explained What to eat and when to prevent complications.
References
- Aminian A, Chang J, Brethauer SA, Kim J. ASMBS updated position statement on bariatric surgery in class I obesity (BMI 30-35 kg/m2). Surgery for Obesity and Related Diseases. 2018;14(8):1071-1087.
- Mechanick JI, Apovian C, Brethauer S, et al. Clinical practice guidelines for the perioperative nutrition, metabolic, and nonsurgical support of patients undergoing bariatric procedures. Endocrine Practice. 2019;25(Suppl 1):1-75.
- Stenberg E, Szabo E, Agren G, et al. Early complications after laparoscopic gastric bypass surgery. Annals of Surgery. 2014;260(6):1040-1047.
- Chang SH, Stoll CR, Song J, et al. The effectiveness and risks of bariatric surgery: An updated systematic review and meta-analysis. JAMA Surgery. 2014;149(3):275-287.