HIEN T. NGUYEN, M.D.
A 40-year-old woman is on the liver transplant list for Laennec’s cirrhosis with a MELD (Model for End-stage Liver Disease) score of 9. She presented to the hernia clinic with multiple recurrent abdominal wall hernias, resulting from prior operations. Her transplant team and I have followed her for a number of months, with the plan of repairing the hernias at the same time that she gets her liver transplant. However, she complains of worsening pain over the enlarging hernias with worrisome obstructive symptoms of nausea and vomiting. A CT scan of her abdomen shows intestine incarcerated within one of the hernias, as well as contracted and fibrotic rectus muscles. Despite the higher risks of surgery and subsequent hernias due to her cirrhosis, the patient wanted the hernia fixed as soon as possible due to intense pain.
The MELD score originally was used to predict three-month mortality after a transjugular intrahepatic portosystemic shunt (TIPS) procedure. TIPS was used to decrease portal hypertension from liver cirrhosis in an effort to decrease complications such as ascites, encephalopathy, and varices within the esophagus, stomach and anorectum. MELD currently is used by the United Network for Organ Sharing (UNOS) to prioritize patients for liver transplants. It is determined by serum bilirubin, INR and creatinine. Higher scores indicate a higher mortality; a score of 9 to 12 correlates with a mortality of 5 to 10%.
Surgery leads to a transient decrease in perfusion to the liver, a worrisome condition for a patient with cirrhosis. Certain anesthetic agents in surgery can decrease hepatic blood flow by 30%. Further, intraoperative hypertension can occur due to vasoactive drugs, intermittent positive pressure ventilation, and splanchnic vasodilation triggered by retraction of abdominal viscera.
In addition, a cirrhotic liver does not metabolize effectively, and leads to an increase in the volume of distribution for administered medications. Given the complex and recurrent nature of the hernia, the operation typically takes at least three hours to complete. Coordination with multiple teams is necessary to undertake such an operation, including anesthesia, critical care, gastrointestinal medicine and the transplant team.
A physician performing this type of hernia operation for this patient must take into consideration her current medical conditions and future medical and surgical issues. The surgeon’s repair must give her the best chance of healing without recurrence, while minimizing the risk of worsening her medical conditions and anticipating potential future sequelae of her disease. For example, a future transplant operation will require an incision through the abdominal wall, thereby dividing the hernia repair. Due to the multitude of surgical challenges, including the size of the hernia, the number of defects, and the scar tissue from prior operations, a posterior component separation was used to reconstruct her abdominal wall. This required division of the transversus abdominus muscles on both sides, which allowed the contracted rectus muscles to be brought back to midline, and closure of the hernia defects. When divided, the transversus abdominus muscles, corset-like muscles that lie posterior to the obliques, allow the rectus muscles to be mobilized medially and the hernia defects to be closed with minimal tension.
Mesh is also necessary to decrease the risk of recurrence, while also off-loading the tension on the repair of the defect. In this case, a large piece of biologic mesh was chosen to reinforce the repair. This mesh is designed to incorporate into the abdominal wall musculature, and withstands infection better than synthetic mesh. In a patient with cirrhosis, poor wound healing and future worsening ascites and overall metabolic function are likely, which can lead to further infection risks. Also, incorporation of the biologic mesh into the musculature allows future operations such as a liver transplant to be performed with the lower risk of hernia recurrence.
The operation was performed in less than three hours, and the patient was admitted to the surgical ICU to monitor for signs of hepatic decompensation. Postoperatively, her MELD score increased to 12, but she remained stable after surgery, and tolerated a diet on post-operative day 2. She was sent home on postoperative day 4 with close follow-up by her medical and surgical team, and continues to do well.
Hien T. Nguyen, M.D., FACS, is director, Comprehensive Hernia Center, Johns Hopkins Bayview Medical Center. He can be reached at email@example.com.