Thoracotomy patch repair of large diaphragmatic herniae in a porcine model: a tale of two patches.

Abstract

Congenital diaphragmatic herniae (CDH) may require patch closure in 50% of the cases. We assessed a biologic and composite mesh in aporcineCDH model. Left sided thoracotomy was performed in 20 pigs. Approximately, 30% of the diaphragm was excised and the patch (Surgisis® or Parietex®) inserted to close this defect. The pigs were killed at 6months and the diaphragm was harvested for biomechanical and histological assessment. The mean weight of the pigs at surgery and killing were 6.1kg (4.2-8.4kg) and 94.1kg (80-131kg), respectively. There were two recurrences and three eventrations, all with Surgisis®. There were less dense lung and abdominal adhesions in the Parietex group (P < 0.0001 and 0.025, respectively). The tensile strength of the Surgisis®, the Parietex® groups and controls were similar. There was significantly more muscle in-growth in the Parietex® patch over Surgisis® (p = 0.016). Parietex® and Surgisis® patches at 6months have a similar tensile strength to normal tissue. All recurrences and eventrations were in the Surgisis® group. Parietex® patches demonstrated more muscle in-growth into the patch compared to Surgisis®. This is the first study utilising Parietex® composite patch in the repair of large diaphragmatic defects in a porcine model.