Closure of rabbit ileum enterotomies with the argon and CO2 lasers: Bursting pressures and histology

Abstract

In this study, we examined short‐term strength and histology of experimental argon and CO₂ laser‐welded and control‐sutured enterotomies in a rabbit model. Longitudinal 1.0‐cm enterotomies were closed with the argon laser at 0.5 (n = 10) or 1.0 (n = 10) W power and a spot diameter of 2.8 mm resulting in energy fluences of 230 and 450 J/cm², respectively. Similar enterotomies were closed using the CO₂ laser at 0.5 (n = 10) or 1.0 (n = 10) W power and a spot diameter of 1.2 mm, resulting in energy fluences of 1,360 and 2,730 J/cm². In all closures, continuous wave laser was delivered for 30 seconds. Using a pressuremonitored infusion system with normal saline, the pressure required to burst each weld as well as sutured controls (n = 10) was recorded approximately 1 minute following fusion. Mean bursting pressures for the argon laser at 0.5 W and 1.0 W were 34.1 ± 19.4 mm Hg (mean ± SD) and 17.3 ± 8.3 mm Hg, respectively, and for the CO₂ laser were 23.5 ± 12.0 mm Hg and 31.8 ± 15.6 mm Hg, respectively. Sutured controls leaked at 45.2 ± 12.0 mm Hg. With the exception of argon‐laser welds at an energy fluence of 450 J/cm², which were less than sutured repairs, the bursting pressures for welded closures were not significantly different from the sutured controls (Student's t distribution, P < .05). Histologic examination of both types of welds demonstrated a fibrin and red blood cell coagulum bridging the anastamosis, with some evidence of mild thermal injury at the mucosa. These findings suggest that both the argon and the CO₂ lasers present an alternative means to suturing in closure of small‐bowel enterotomies.