Investigating the Benefit of Fluorescence in Acute Mesenteric Ischaemia: A Systematic Review and Narrative Synthesis

Acute Mesenteric Ischaemia (AMI) is a life-threatening surgical emergency, with a high mortality rate. Timely revascularisation is crucial to avoid bowel necrosis; however, once tissue becomes non-viable, surgical resection is necessary. Delineating viability is a critical challenge. Indocyanine Green (ICG) fluorescence, used to visualise tissue perfusion in elective resections, could be used to assess bowel perfusion in the emergency setting. This narrative synthesis aims to evaluate the benefit of intraoperative ICG in the context of AMI.

A systematic review following PRISMA guidelines was conducted according to a predefined protocol (PROSPERO ID: 42024581088). The following electronic databases were interrogated between January 1st 1945 and 1st May 2024: EMBASE and Medline (via OVID). All studies that investigated the use of ICG in the management of AMI were considered.

The search returned 2941 articles. 84 abstracts were reviewed leaving 6 articles with a total of 196 patients for full assessment and which were included in the final narrative synthesis. Macroscopic perfusion assessment was inconsistent with ICG in 35% of cases, with ICG proposing more conservative resection in 75%. No statistically significant difference in re-look rates, morbidity or mortality was found when comparing ICG to visual assessment alone.

ICG may reduce length of bowel resection and both planned and unplanned re-look laparotomies. Outcomes reporting is sparse and comparative studies lacking. Randomised studies comparing ICG against direct light are needed. Improved intraoperative decision-making using ICG could optimise resection boundaries, enhance patient outcomes and reduce mortality in this critical population.