Abdominal surgery always carries a risk of complications, one of which is internal hernia. Internal hernia is a protrusion of tissue through an abnormal opening in the mesentery, a support structure of the intestines. Previous abdominal surgery is the most common cause of internal hernia (Ghiassi et al. 2007). Some procedures carry a higher risk of this complication than others, especially laparoscopic gastric bypass surgery, a form of weight-loss surgery.
Abdominal Procedures with a High Risk of Internal Hernia
The procedures that carry the highest risk of internal hernia are those involving damage or defects to the mesentery. Traumatic injuries can damage the mesentery, so internal hernia can occur after abdominal surgery to repair trauma. However, these hernias are attributed to the initial trauma rather than to the surgery. A type of weight-loss surgery called laparoscopic Roux-en-Y gastric bypass involves intentionally creating a defect in the mesentery, so internal hernia is a significant risk after this type of abdominal surgery.
Roux-en-Y gastric bypass is a type of abdominal surgery in which a small portion of the stomach, the part nearest the esophagus, is closed off and connected to the small intestine beyond the duodenum. The duodenum and most of the stomach are left in place as a non-functioning "branch" of the digestive tract. A diagram of the reconstructed digestive tract looks like the letter Y, giving the procedure its name.
This procedure requires resecting (cutting and re-stitching) the small intestine, causing a defect in the mesentery. Internal hernia after this abdominal surgery occurs in perhaps 2% of patients (based on Parakh et al. 2007).
Who is at Risk of Internal Hernia After Abdominal Surgery?
Patients most at risk of developing an internal hernia after abdominal surgery, especially weight loss surgery, may be those with the fastest post-surgery weight loss. Extremely fast weight loss may make it easier for the small bowel to pass through mesentery defects. (Medical News Today 2008)
In patients who have undergone gastric bypass surgery, the risk of internal hernia is higher for those who had laparascopic surgery (also called keyhole surgery or "band-aid" surgery because of the small incisions) than for those who had conventional, open surgery. This may be because of the decreased amount of scarring (adhesions) resulting from laparoscopic surgery (Jeansonne et al. 2007).
Because of the changes that occur in the body during pregnancy, pregnant women appear to be at an increased risk of an internal hernia if they have a history of abdominal surgery. The hernia may occur early or late in the pregnancy (case reports include occurrences at 12 weeks and at 34 weeks gestation, Kakarla et al. 2005).
Internal hernia is not a common complication of abdominal surgery, but people at risk should be aware of the possibility. An internal hernia should be treated as an emergency because the blood supply can be cut off to the herniated tissue, causing it to die. If you have had abdominal surgery for trauma or weight loss, make sure you discuss your risk with your treatment team.
- Saber Ghiassi, Scott Q. Nguyen, Celia M. Divino, John C. Byrn and Avraham Schlager. "Internal Hernias: Clinical Findings, Management, and Outcomes in 49 Nonbariatric Cases." Journal of Gastrointestinal Surgery 2007;11(3):291-295.
- Louis O. Jeansonne IV, M.D.; Craig B. Morgenthal, M.D.; Brent C. White, M.D.; and Edward Lin, D.O. "Internal Hernia after Laparoscopic Gastric Bypass: A Review of the Literature." Surgical Perspective 2007.
- N. Kakarla, C. Dailey, T. Marino, S. A. Shikora, and D. Chelmow. "Pregnancy after gastric bypass surgery and internal hernia formation." Obstetrics and Gynecology 2005;105(5 Pt 2):1195-8.
- "Periods of Excessive and Rapid Weight Loss May Be Associated With Internal Hernia After Bariatric Surgery." Medical News Today 2008.
- S. Parakh, E. Soto, and S. Merola. "Diagnosis and management of internal hernias after laparoscopic gastric bypass." Obesity Surgery 2007;17(11):1498-1502.