Petersen's Hernia in a Pregnant Woman Following Roux-en-Y Gastric Bypass Surgery: The Importance of Emergency Surgical Treatment.

Roux-en-Y gastric bypass (RYGB) patients are at risk of creating potential spaces for possible internal hernias during the procedure. During pregnancy, the pregnant uterus elevates the bowel, increasing intra-abdominal pressure. Cases reported to date have described mild abdominal pain and no evidence of peritoneal irritation, with inconclusive ultrasound and MRI findings for diagnosis of Petersen's hernia. We present the case of a 42-year-old female patient with a history of RYGB eight years earlier without complications, with a pregnancy of 34 weeks of gestation. Symptomatology began with colicky abdominal pain in the epigastric, with irradiation to the right upper quadrant. On physical examination, revealed a painful abdomen on the median and deep palpation in the epigastric and right upper quadrant, the rest of the studies were inconclusive. As there was no improvement of the symptoms in 12 hours, an emergency diagnostic laparoscopy was performed, finding a strangulated Petersen's hernia requiring resection, with the closure of the gastric pouch, intestinal anastomosis, and Stamm gastrostomy with closure of the mesenteric gap. Therefore, a pregnant patient presenting with upper quadrant abdominal pain with a history of RYGB, even one with normal labs and imaging, should be assumed to have an internal hernia until proven otherwise. The emergency surgical approach is associated with early resolution and prevents its progression with catastrophic results.