Case Presentation: A 53-year-old female with history of Roux-en-y bypass, hypertension, and type 2 diabetes mellitus presented to the emergency department following a mechanical fall. She was found to have a right femoral neck fracture and was admitted for surgical repair. There were no apparent intraoperative complications. Upon arrival to the general care floor shortly after her surgery, she developed acute, severe abdominal pain and hypotension. Arterial blood gas demonstrated mild metabolic acidosis (pH: 7.26, pCO2: 41, bicarbonate: 18.5) and lactate of 0.8. The remainder of her labs (i.e., complete metabolic panel, complete blood count) were relatively unremarkable.Initial differential was broad, ranging from ischemic bowel injury related to anesthesia or cardiac event, small bowel obstruction, perforated gastric or duodenal ulceration, acute cholecystitis, acute colonic pseudo-obstruction, and propofol-induced pancreatitis. Stat abdominal x-ray revealed dilated bowel loops in the right hemipelvis, prompting a stat CT abdomen/pelvis with and without contrast. CT demonstrated an internal, likely Petersen type hernia with associated twisting of the mesentery and resultant severe small bowel mesenteric congestion, bowel wall thickening, and edema with decreased small bowel enhancement concerning for developing ischemia. Repeat venous blood gas showed a worsening pH (7.17) and increased lactate (2.1), consistent with developing ischemia.The patient underwent urgent laparoscopic surgery with general surgery. She was found to have herniation of her entire small bowel through the Petersen defect with resulting volvulus upon itself. Detorsion of the volvulus and reduction of the hernia through the Petersen defect was performed and the defect was closed. She then had an uneventful recovery.
Discussion: Petersen defects can occur after Roux-en-y bypass via a defect between Roux limb along the jejunal mesentery and the transverse mesocolon. Internal herniation can occur through this defect. Patient position during surgery may have increased the risk of this occurring. While generally well-tolerated, total hip arthroplasty and similar hip surgeries carry a low risk of intra-abdominal complications. A single center retrospective study of 9628 orthopedic patients identified 8 acute abdominal complications, including acute cholecystitis, volvulus, toxic megacolon, and acute colonic pseudo-obstruction. Overall, literature indicates that acute abdominal pain post-orthopedic surgery is frequently a combination of physical issues with the prosthesis itself, but there is also a small risk of systemic issues related to underlying anesthesia or anatomic concerns.
Conclusions: Acute abdominal pain following hip surgery is rare. Hospitalists providing perioperative management should be aware of the broad differential for post-hip arthroplasty abdominal pain. For patients with a history of bariatric surgery, internal herniation should additionally be considered. Given the increased prevalence in Roux-en-y bypass surgeries, it is possible that this complication with become more common.
