Comparison of bursting pressure of abdominal wall defects repaired by three conventional techniques

Still debated are the appropriate techniques for the repair of abdominal wall defects and the methods used to measure their strength. Although tension has been used in many studies to test wound strength, bursting pressure reflects more accurately the pathophysiology of wound dehiscence. The aim of the current study was to evaluate three different techniques for closure of abdominal wall defects using a new and more accurate device for bursting pressure measurements. Full thickness abdominal wall defects measuring 2 cm2 were created in 43 anesthetized rats randomly assigned to three groups: simple primary closure (n = 15), Mayo repair (n = 14), and primary closure reinforced with a mesh (n = 14). Thirty days after surgery, the rats were sacrificed. The abdominal wall was fully excised and placed over a bursting chamber made of a metal cylinder connected to a carbon dioxide source with a control valve and a manometer. Gas was gradually released while the pressure was recorded until bursting occurred. Disruption of all closures occurred at the point where the suture itself penetrated the tissue. The average bursting pressure was 1383 +/- 299 mm Hg for the primary closure group, 1200 +/- 409 mm Hg for the mesh reinforcement group, and 1607 +/- 337 mm Hg for the imbrication repair (Mayo) group (P < 0.03). The data suggests an advantage for the Mayo repair over the other two repairs. The bursting chamber tested is a new and more reliable method to study techniques and conditions influencing the strength of abdominal wall closure.