Q&A about Bariatric Surgery
Q: What are the criteria for bariatric surgery?
A: Bariatric surgery focuses on treating diseases related to obesity, such as diabetes, hypertension, fatty liver, sleep apnea, heart disease, osteoarthritis, etc. It is also performed to prevent or reduce the risk of certain types of cancer, such as colon cancer, breast cancer, and endometrial cancer.
Before surgery, the doctor will provide detailed information to the patient, perform a physical examination to assess readiness, and screen for suitable candidates who meet the following indications: patients who have failed to lose weight with other methods.
Currently, the criteria in Thailand are as follows:
• Body Mass Index (BMI) > 27.5 kg/m² with obesity-related comorbidities that cannot be controlled by weight loss
• Body Mass Index (BMI) > 32.5 kg/m² with obesity-related comorbidities
• Body Mass Index (BMI) > 37.5 kg/m² without the need for obesity-related comorbidities
• Patients who have no contraindications for surgery and are able to take care of themselves after surgery
However, the global trend for surgical indications has now shifted towards lower BMI values. Based on the latest data from 2022 onwards, according to the guidelines of the American Society for Metabolic and Bariatric Surgery (ASMBS) and the International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO), it is found that the surgical indication criteria may be adjusted to:
• Body Mass Index (BMI) > 30 kg/m² with obesity-related comorbidities
• Body Mass Index (BMI) > 35 kg/m² without the need for obesity-related comorbidities
Especially in obese patients of Asian descent, who may benefit from bariatric surgery at a BMI > 27.5 kg/m².
However, in patients with lower BMI, it is recommended to consider other weight loss methods first, and only proceed with bariatric surgery as the final option if other methods are unsuccessful.
Q: At what age can bariatric surgery be performed?
A: The appropriate age for bariatric surgery is between 18–65 years old. However, based on the latest information from 2022 onwards, according to the guidelines of the American Society for Metabolic and Bariatric Surgery (ASMBS) and the International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO), bariatric surgery in adolescents aged 12–18 years or elderly patients aged 65–70 years can also be safely and effectively performed.
However, the decision must be based on the strength and specific indications of each patient, evaluated by a multidisciplinary team.
Q: If a patient has underlying diseases such as diabetes or hypertension, can bariatric surgery still be performed?
A: Patients with obesity-related underlying diseases such as diabetes or hypertension can safely undergo bariatric surgery.
Moreover, surgery can help cure or significantly improve diabetes or hypertension.
Before surgery, it is recommended that patients continue taking medications to control diabetes and hypertension consistently until the day of surgery.

Q: Is it true that bariatric surgery can help control diabetes and hypertension?
A: It is true, especially in cases where diabetes or hypertension cannot be controlled with medication.
Bariatric surgery can help improve disease control, and in some cases, if diabetes has not been present for a long time and the patient is young, there is a high chance of complete remission from diabetes.
Medical research data show that delaying bariatric surgery for every one year after the onset of diabetes reduces the chance of remission by approximately 7%.

Q: Are there any limitations that would prevent someone from undergoing bariatric surgery?
A: Currently, the contraindication for bariatric surgery is patients who are not strong enough to undergo surgery.
In all cases, doctors will always perform a preoperative health evaluation before proceeding with surgery.

Q: How many types of bariatric surgery are there nowadays?
A: There are many types of bariatric surgery, but currently, there are four popular methods as follows:
Methods of bariatric surgery

1. Sleeve Gastrectomy: sleeve gastrectomy is a laparoscopic surgery that uses a triple-layer stapling device to cut and resize the stomach, reducing its size to about 15–20%.
This surgery adjusts the hormone Ghrelin, which controls appetite, resulting in reduced food intake and effective weight loss, with excess weight loss of about 60–70%.

2. Roux-en-Y Gastric Bypass: roux-en-Y gastric bypass is a laparoscopic surgery in which the end of the esophagus connected to the stomach is cut and reconnected directly to the intestine.
This surgery adjusts the hormone Ghrelin, which controls appetite, leading to reduced food intake and also reducing nutrient absorption. As a result, it enhances weight loss and more effectively treats obesity-related diseases. It results in significant weight loss, with excess weight loss of about 70–80%.

3. Sleeve Gastrectomy Plus Proximal Jejunal Bypass
This is the latest technique and has become popular abroad.
It is a laparoscopic surgery that partially removes the stomach, reducing its size to about 15–20%, and adjusts the hormone Ghrelin to decrease appetite, resulting in reduced food intake.
At the same time, a new connection is created in the small intestine to reduce nutrient absorption, leading to greater weight loss and better treatment of obesity-related diseases.
It has been found to have lower complication rates compared to gastric bypass surgery, while achieving similar weight loss results, with excess weight loss of about 70–80%.

4. Gastric Banding
Gastric banding helps reduce food intake.
Currently, this method is not very popular because, in the long term, it may cause health problems.

Q: How do the different bariatric surgery techniques differ?
Comparison of each surgical technique
Criteria    Sleeve Gastrectomy    Roux-en-Y Gastric Bypass    Sleeve Gastrectomy Plus
Suitable BMI    32.5–50 kg/m²    >45 kg/m²    >45 kg/m²
Recovery after surgery    Fast    Moderate    Fast
Weight loss after surgery*    60–70%    70–80%    70–80%
Chance of remission of diabetes and other comorbidities    High    Very high    Very high
In case of severe gastroesophageal reflux disease (GERD)    Not suitable    Suitable    Not suitable
Risk of short-term complications    Low    Moderate    Low
Risk of long-term complications    Low    Moderate    Low
Q: Are there any side effects from bariatric surgery?
A: according to the latest information from 2022 onwards, based on the guidelines of the American Society for Metabolic and Bariatric Surgery (ASMBS) and the International Federation for the Surgery of Obesity and Metabolic Disorders (IFSO), it is found that in the long term, bariatric surgery is safe and provides the most effective weight loss compared to other methods such as medication or weight loss balloons.
In the short term, there are general surgical risks, such as intra-abdominal bleeding, gastric leakage, or deep vein thrombosis.
However, when performed by a surgeon specialized in bariatric surgery, the risk is very low, at less than 1%.

Q: What kind of surgical wounds will there be after bariatric surgery?
A: the surgical wounds on the abdomen are small laparoscopic wounds, 0.5–1.2 cm in size, with 3–4 incisions.
All wounds are closed with dissolvable sutures, and they will generally heal within 10–14 days after surgery.

Q: How should one prepare for bariatric surgery?
A: preparation before bariatric surgery includes:
•  Stop all alcohol and smoking 2 weeks before coming to the hospital.
•  1 day before coming to the hospital, eat soft, easily digestible food, and avoid spicy or highly seasoned food.
•  Continue taking medications for underlying diseases as usual (except for blood thinners, which should be stopped 5–7 days before surgery).
•  Clean fingernails and toenails, and remove any nail polish.
•  Get enough sleep, about 7–8 hours per day.

Q: After bariatric surgery, is there a chance of gaining weight again?
A: although bariatric surgery is the method that results in the greatest and most long-lasting weight loss, if the patient does not maintain proper self-care after surgery — especially if they have habits such as drinking sweet beverages or fruit juices regularly — there is a chance of regaining weight.
However, the chance of regaining weight to the original level is very low, at less than 2.5%.

Q: What are the causes of regaining weight after surgery?
A: the causes are poor self-care after surgery and habits such as regularly drinking sweet beverages and fruit juices.
Q: How many days of recovery are needed after bariatric surgery?
A: the total hospital stay is 4–5 days :
•  Day 1: Hospital admission in the morning or afternoon for preoperative health check-ups.
•  Day 2: Upper gastrointestinal endoscopy and laparoscopic surgery under general anesthesia.
•  Days 3–5: Recovery in the hospital, with discharge around noon on Day 4 or Day 5.
Q: Will the surgically altered stomach affect daily life?
A: the stomach after surgery will be strong and healthy.
However, because of the reduced stomach size, patients need to adjust their eating behaviors, such as eating more protein, chewing slowly, and avoiding drinking water 30 minutes before and after meals.

Q: How should food be consumed after bariatric surgery, and for how long?
A: there are several dietary plans after surgery, but generally, they are divided as follows:
•  Days 1–2: It is recommended to consume water, herbal drinks, or clear fluids without added sugar.
•  Next 2–3 days: It is recommended to consume high-protein milk, medical-grade nutritional drinks, Greek yogurt, unsweetened soy milk, or thick high-protein liquids.
•  Next 3–14 days: It is recommended to consume soft, easily digestible, low-fiber foods, such as steamed eggs, small pieces of steamed fish, or vegetable soup with boiled salmon.
•  After 14–30 days: It is recommended to consume high-protein foods, such as clear tofu soup with minced pork, fish steaks, or chicken steaks.
Q: When can normal food be consumed?
A: Approximately 30 days after surgery, patients can start consuming normal food.
However, it is still recommended to focus on high-protein foods, and to avoid rice, starches, sugar, sweet drinks, and fruits.
Fried and greasy foods should also be avoided.
It is important to drink enough water, about 1.5–2 liters per day, to help with metabolism and maintain body hydration.
Alcohol, carbonated beverages, and sweet drinks should be avoided.

Q: How many follow-up visits are needed after bariatric surgery?
A: After surgery, follow-up appointments are scheduled as follows:
•  Every 2 weeks after surgery: to check the surgical wounds and provide additional dietary advice.
•  3 months after surgery: to check that body weight has decreased by 20% and assess general blood tests, such as HbA1c and blood lipid levels.
•  6 months after surgery: to check that body weight has decreased by 30% and reassess general blood tests, including an ultrasound to check if fatty liver disease has resolved.

Q: If bariatric surgery has already been performed once, can it be performed again?
A: If bariatric surgery has been previously performed, a repeat surgery can be considered if the patient's weight remains high (BMI > 30) or if obesity-related diseases such as diabetes, hypertension, fatty liver, or sleep apnea are not well controlled.
Q: Can bariatric surgery and gallstone surgery be performed at the same time?
A: Bariatric surgery combined with gallstone surgery can be performed, but only by specialized surgeons.
This is because the surgery is more difficult and complex than usual, especially in patients with very high body weight who may also have fatty liver, which can make gallstone surgery even more challenging.
However, it can still be performed by expert surgeons, and it usually adds about 1–2 hours to the surgery time, without increasing the number of incisions compared to standard bariatric surgery.