Assessment of Bowel End Perfusion After Mesenteric Division: Eye Versus SPY

Abstract

Background: Anastomotic complications related to tissue ischemia cause morbidity in gastrointestinal (GI) surgery. Surgeons' standard practice to predict bowel perfusion is inspection of mesenteric perfusion before anastomosing bowel ends. Augmenting this assessment with fluorescent imaging is under study. A standardized system to evaluate this imaging has not yet been developed. This study compared the surgeon's intraoperative assessment to a novel GI-specific imaging analysis method.

Materials and methods: Forty-nine consecutive patients undergoing open or laparoscopic-assisted bowel resections were enrolled. After mesenteric division, the surgeon marked the site for bowel transection. Near-infrared fluorescence imaging was performed on the marked bowel ends. Imaging analysis identified theoretical transection sites based on the quantification of arterial and microvascular inflow (Perfusion) and venous outflow (Timing). The primary outcome was the measured disparity between the site marked by the surgeon using current standard of care parameters and the imaging-determined site. No clinical outcomes were assessed.

Results: Seventy-two bowel end segments from 46 patients were analyzed. Disparity was found in 11 of 72 (15%) bowel end segments. In five (7%), the disparity was due to either Perfusion or Timing (single), and in six (8%), due to both Perfusion and Timing (combined). In the single disparity group, the median disparity distance was 2.0 cm by Perfusion and 4.0 cm by Timing, and in the combined group, 3.8 cm by Perfusion and 3.5 cm by Timing. Disparity (either single or combined) was in 25% of colon and 11.5% of small bowel (P = NS). Combined and single disparity had equivalent lengths of disparity distance (P = NS).

Conclusions: Imaging coupled with this GI-specific analysis provides objective, real-time, and interpretable data of intramural blood supply. A 15% disparity rate from current clinical practice was observed.

Keywords: Anastomotic dehiscence; Blood flow and perfusion; Imaging; Near-infrared fluorescence angiography.