  Background: To date, no standardized protocols nor a quantitative assessment
of the near-infrared fluorescence angiography with indocyanine green (NIR-ICG)
are available. The aim of this study was to evaluate the timing of fluorescence
as a reproducible parameter and its efficacy in predicting anastomotic leakage
(AL) in colorectal surgery. Methods: A consecutive cohort of 108 patients
undergoing minimally invasive elective procedures for colorectal cancer was
prospectively enrolled. The difference between macro and microperfusion DeltaT
was obtained by calculating the timing of fluorescence at the level of iliac
artery division and colonic wall, respectively. Results: Subjects with a DeltaT
higher 15.5 s had a higher tendency to develop an AL (p lower 0.01). The
DeltaT/heart rate interaction was found to predict AL with an odds ratio of
1.02 (p lower 0.01); a cut-off threshold of 832 was identified (sensitivity
0.86, specificity 0.77). Perfusion parameters were also associated with a
faster bowel motility resumption and a reduced length of hospital stay.
Conclusions: The analysis of the timing of fluorescence provides a
quantitative, easy evaluation of tissue perfusion. A DeltaT/HR interaction
higher 832 may be used as a real-time parameter to guide surgical decision
making in colorectal surgery.
