The port-decompression effect. A causative factor in the aetiology of post-laparoscopic port-site herniation?

Introduction Post-laparoscopic port-site herniation has been variously repo rted to have an incidence of up to 0.2%. In 86% of instances where port siz es of 10 mm or greater have been used, and lateral port sites are 35 times more at risk than suprapubic, with the umbilical locale being the most comm on site, associated with 75% of all hernias. Theory A port decompressing an abdomen insufflated to a pressure of 15 mmHg has a profound suction effect and can pick up a loop of bowel while being drawn out through the abdominal wall. We believe that, on occasion, this is the mechanism by which bowel can be drawn within the abdominal wall and re ctus sheath defect, thereby contributing to port-site herniation. Methods We have obtained photographic evidence of bowel drawn up into a cha nnel formed by a primary trocar. We demonstrate how bowel is caught by the suction effect of decompression through an open port and show that, despite the intraumbilical entry technique favoured by Garry, a channel can form t hrough the abdominal wall which can trap bowel. We also examine the physics of gas flow and the relationship between port size, decompression techniqu e and suction effect. Conclusion We suggest the abdomen should be decompressed slowly under direc t vision, through the side tap, with the telescope remaining within the por t. After gas release is completed, the primary port and telescope are remov ed together, with a clear view at all times that the port is free of any en trapped bowel.