Examination of abdominal wall perfusion using varying suture techniques for midline abdominal laparotomy closure.

Background: With a growing interest in the primary prevention of incisional hernias, it has been hypothesized that different suturing techniques may cause various levels of tissue ischemia. Using ICG laser-induced fluorescence angiography (ICG-FA), we studied the effect of different suture materials and closure techniques on abdominal wall perfusion.

Methods: Fifteen porcine subjects underwent midline laparotomy, bilateral skin flap creation, and three separate 7 cm midline fascial incisions. Animals underwent fascial closure with 5 different techniques: (1) Running 0-PDS® II (polydioxanone) Suture with large bites; (2) Running 0-PDS II Suture with small bites; (3) Interrupted figure-of-eight (8) PDS II Suture, (4) Running 0-barbed STRATAFIX™ Symmetric PDS™ Plus Knotless Tissue Control Device large bite; (5) Running 0-STRATAFIX Symmetric PDS Plus Device small bites. ICG-FA signal intensity was recorded prior to fascial incision (baseline), immediately following fascial closure (closure), and at one-week (1-week.). Post-mortem, the abdominal walls were analyzed for inflammation, neovascularity, and necrosis.

Results: PDS II Suture with small bites, fascial closure at the caudal 1/3 of the abdominal wall, and the 1-week time period were all independently associated with increased tissue perfusion. There was also a significant increase in tissue perfusion from closure to 1-week when using small bites PDS II Suture compared to PDS II Suture figure-of-8 (p < 0.001) and a trend towards significance when compared with large bites PDS II Suture (p = 0.056). Additionally, the change in perfusion from baseline to 1 week with small bites was higher than with figure of 8 (p = 0.002). Across all locations, small bite PDS II Suture has greater total inflammation than figure of 8 (p < 0.001).

Conclusions: The results suggest that the small bite technique increases abdominal wall perfusion and ICG-FA technology can reliably map abdominal wall perfusion. This finding may help explain the reduced incisional hernia rates seen in clinical studies with the small bite closure technique.