Indocyanine green fluorescence angiography for intraoperative assessment of gastrointestinal anastomotic perfusion: a systematic review of clinical trials

Anastomotic leakage following gastrointestinal surgery remains a frequent and serious complication associated with a high morbidity and mortality. Indocyanine green fluorescence angiography (ICG-FA) is a newly developed technique to measure perfusion intraoperatively. The aim of this paper was to systematically review the literature concerning ICG-FA to assess perfusion during the construction of a primary gastrointestinal anastomosis in order to predict anastomotic leakage. The following four databases PubMed, Scopus, Embase, and Cochrane were independently searched by two authors. Studies were included in the review if they assessed anastomotic perfusion intraoperatively with ICG-FA in order to predict anastomotic leakage in humans. Of 790 screened papers 14 studies were included in this review. Ten studies (n = 916) involved patients with colorectal anastomoses and four studies (n = 214) patients with esophageal anastomoses. All the included studies were cohort studies. Intraoperative ICG-FA assessment of colorectal anastomoses was associated with a reduced risk of anastomotic leakage (n = 23/693; 3.3 % (95 % CI 1.97-4.63 %) compared with no ICG-FA assessment (n = 19/223; 8.5 %; 95 % CI 4.8-12.2 %). The anastomotic leakage rate in patients with esophageal anastomoses and intraoperative ICG-FA assessment was 14 % (n = 30/214). None of the studies involving esophageal anastomoses had a control group without ICG-FA assessment. No randomized controlled trials have been published. ICG-FA seems like a promising method to assess perfusion at the site intended for anastomosis. However, we do not have the sufficient evidence to determine that the method can reduce the leak rate.