The significance of the time to arterial perfusion in intraoperative ICG angiography during colorectal surgery.

Abstract

Intraoperative indocyanine green angiography (ICG-A) is a promising tool to confirm blood supply; however, the assessment is difficult without clear demarcation. In this study, the clinical impact of the time to arterial perfusion (TAP) on anastomotic leakage (AL) was evaluated, especially in patients without ICG demarcation. The TAP was assessed using ICG-A during colorectal surgery in 110 patients. ICG demarcation required changing the transection line, and the TAP was measured at the new stump. The patients were divided into marginal flow (MF) and direct flow (DF) groups according to the arterial route. Delayed TAP was defined as the third quartile or slower TAP in each group. Sixty-six patients (60%) were classified into the MF group, including 64 patients who underwent rectal or sigmoid resection with high ligation of the inferior mesenteric artery. The cut-off value of the delayed TAP in the MF group was significantly slower than that in the DF group (30 and 22s, respectively, p < 0.001). In the entire cohort, the transection line was changed in 2 patients, resulting in no AL. Nevertheless, AL still developed in 6 patients (5.4%), 5 of whom were in the MF group, and delayed TAP was found in 5 of 6 patients. Delayed TAP was significantly associated with AL in the MF group (p = 0.046). In patients without ICG demarcation, delayed TAP might be helpful for predicting the high-risk patients with AL in the MF group; however, performing diverting stoma or strictly careful observation might be a realistic reaction.