08 Apr 2023 Hernia Surgery in Obese

Obesity is a major health problem in our society, with an increasing number of obese individuals including children. Obesity and its interaction with hernia disease are described in the following sections.

First, let me explain who we consider obese. There is a practical calculation method called the Body Mass Index (BMI), which is obtained by dividing body weight by the square of height in meters. The BMI ranges were as follows:

• <18.5 Underweight

• 18.5 – 24.9 Normal weight

• 25 – 29.9 Overweight

• 30 – 34.9 Obesity Class 1

• 35 – 39.9 Obesity Class 2

• >40 Obesity Class 3 – Morbid obesity

• >50 Super obesity

• >60 Super super obesity

Note: This is not applicable to children or the elderly population.

Does obesity cause hernias?

Obesity increases the risk of abdominal wall hernias. Excess weight exerts more pressure on the abdominal wall muscles, causing them to stretch and weaken. Moreover, obesity may cause an existing hernia to grow even further. Obese patients are at a higher risk of developing an incisional hernia after abdominal surgery than non-obese individuals. Additionally, primary or incisional hernia repair is associated with a higher risk of recurrence in obese individuals.

Does obesity prevent hernias?

No. There is a common saying: ‘A little fat covers a multitude of sins.’ This saying has some truth. Inguinal hernias are less common in obese individuals than in thin individuals because fatty tissue fills the hernia defect, preventing other organs from entering and becoming strangulated. However, in reality, obesity can mask an existing hernia, which poses potential risks, and obese patients are less likely to seek medical attention for typical inguinal hernia symptoms and are more likely to present with an incarcerated or strangulated hernia.

In addition, in relation to fatty tissues covering existing hernia defects, patients may experience the emergence of hernias after extreme weight loss or weight loss following surgery for obesity. These patients may say “I lost weight and got a hernia,” when, in fact, the hernia was already present.

I am obese and have a hernia. What should I do?

The only treatment for hernias is surgical repair. As hernias tend to grow over time, early and planned surgery is recommended. Planned surgery is generally a smooth process, particularly in older patients, as incarcerated or strangulated hernias can be life-threatening. In some cases, surgery may be necessary to prevent complications, even in the absence of symptoms.

In obese patients, the characteristics of a hernia, such as its location, size, recurrence risk, and any additional problems, as well as the degree of obesity, should be considered when planning hernia surgery.

As the degree of obesity increases, the risk of complications after hernia surgery increases. Hernia recurrence is the most important risk factor. Therefore, we advise patients to lose weight before surgery. I always say, ‘Surgery begins before surgery.’ When hernias in obese patients cause emergency situations, such as strangulation or obstruction, the risk of complications increases further.

Obese patients should lose weight not only for hernia surgery but also for preparation for other surgical procedures. This is known as prehabilitation. The preoperative period included the patient’s preparation processes leading up to surgery. These mainly involve improving nutrition, quitting smoking, controlling diabetes, treating infections, losing excess weight, and engaging in exercise.

In obese patients, we tend to see more issues with surgical site complications, such as the collection of fluid known as seroma, hematoma, and most importantly, wound and mesh infections. Surgical site infection is the most common cause of surgical incision complications and the most significant cause of hernia recurrence. The second most significant cause is obesity! For abdominal wall hernias (excluding inguinal hernias), mesh infection is seen at rates of 6-10% and is more common in obese patients.

Hernia surgery in extremely obese patients takes longer and they remain longer in the hospital. The likelihood of significant complications such as deep vein thrombosis and pulmonary embolism is higher. Systemic diseases such as diabetes, heart disease, and lung diseases are frequently associated with obesity and increase the risk of complications. Smoking is a serious risk factor for delayed wound healing.

Based on the obesity index, how should hernia surgery be planned?

For inguinal hernias, although it does not pose a significant obstacle, it is recommended that a morbidly obese individual lose weight before undergoing hernia surgery. In fact, for individuals with a BMI > 40, there is a requirement for obesity surgery without any other criteria. For the 35-40 range, when there are additional health problems such as diabetes, hypertension, high cholesterol, and sleep apnea, there is an indication for obesity surgery. In these patients, hernia surgery should be postponed until after obesity surgery.

For obese patients with abdominal wall hernias, the plan should be based on the characteristics of the hernia and the degree of obesity. Laparoscopic methods are recommended for repairing abdominal wall hernias (umbilical, epigastric, and surgical hernias) in patients with obesity. Laparoscopic ventral hernia repairs have advantages over open hernia repairs, including less wound infection, less pain, fewer wound problems (hematoma and seroma), and shorter hospital stays.

In patients who require obesity surgery, such as those with abdominal wall hernias, repair should be performed 1 year after surgery as a general approach. However, this should not be postponed in cases of rapid growth, pain, compression, or suffocation. Laparoscopic repair should be the primary consideration if performed simultaneously.

Studies have shown that the BMI threshold for complicated abdominal wall hernia repair in obese patients was 46.

Can hernia surgery be performed simultaneously with obesity surgery?

No. Scientific studies have shown that when performed simultaneously, it increases the risk of wound site problems, mesh infection, and recurrence. Therefore, it is not recommended. There is insufficient data available on the long-term outcomes of hernia repair with mesh in this group of patients. It is more appropriate to perform hernia repair after weight loss through diet, exercise, or surgery for obesity. Why?

This is technically easier to achieve. The risk of recurrence is low. The risk of complications is low. The wound heals rapidly and improves. It involves a faster and less painful recovery process. In addition, excess skin resulting from weight loss can be eliminated during the same surgery (abdominoplasty).

Another important point is that, especially after repairing an abdominal wall hernia, excessive weight increases the risk of hernia recurrence.

In summary, there is no consensus on performing hernia surgery in obese patients. The decision should be made based on the surgeon’s knowledge and experience, the patient’s complaints, the characteristics of the hernia, the type of obesity surgery selected, and the patient’s preference.