Anastomotic leak rates in patients undergoing colorectal surgery with or without intraoperative infrared thermography: pilot randomized controlled study

Background: Anastomotic leak (AL) is a devastating complication of colorectal surgery causing high morbidity and sometimes mortality. Well perfused bowel segment is a prerequisite for anastomotic healing. Conventional methods to detect bowel perfusion are insensitive in predicting AL. Objective assessment of bowel perfusion like intraoperative infrared thermography (IRT) can accurately delineate well perfused segment of bowel for anastomoses and may reduce AL rates. The aim of our study was to compare AL rates in colorectal surgery with or without use of intraoperative IRT. Methods: Forty-three adult patients undergoing elective colorectal surgery with resection and anastomosis were randomized into a test and control group. In the control group resection and anastomosis were done using the conventional method. In the test group after devascularisation, the resection line was marked on the bowel wall and IRT done using a forward looking infrared camera with a rainbow display. Resection line was determined by a sharp change in color on the display screen (corresponding to >3°C change in surface temperature) over the visualized bowel wall. Margins were revised if difference between surgeon and IRT determined resection lines were more than 1 cm apart. Anastomosis was done as per surgeon’s preference.AL was the primary outcome measure. Hospital stay, operative time, blood loss, postoperative complications as per Clavien–Dindo classification were the secondary outcome measures. Results: Twenty patients each in test and control group were analyzed. Fourteen out of 20 patients in the test group had their margins revised based on IRT. One patient in the test group (IRT) and three patients in the control group had AL. This difference was not statistically significant ( P = 0.605). The relative risk of AL in control group was 1.59 vs. 0.47 in the test group. There was no significant difference in operative time, blood loss, hospital stay, mortality, or complications based on Clavien–Dindo score between the two groups. Conclusion: Intraoperative IRT is a safe and sensitive method to assess bowel perfusion and may be used as an adjunct in colorectal surgery to reduce AL. Larger trials are required before IRT can be routinely recommended in colorectal surgery.