Influence of intraoperative vasopressor use on indocyanine green fluorescence angiography: first evaluation in an experimental model

Abstract

Intraoperative indocyanine green (ICG) fluorescence angiography has gained popularity and acceptance in many surgical fields for the real-time assessment of tissue perfusion. Although vasopressors have the potential to preclude an accurate assessment of tissue perfusion, there is a lack of literature with regards to its effect on ICG fluorescence angiography. An experimental porcine model was used to expose the small bowel for quantitative tissue perfusion assessment. Three increasing doses of norepinephrine infusion (0.1, 0.5, and 1.0 µg/kg/min) were administered intravenously over a 25-min interval. Time-to-peak fluorescence intensity (TTP) was the primary outcome. Secondary outcomes included absolute fluorescence intensity and local capillary lactate (LCL) levels. Five large pigs (mean weight: 40.3 ± 4.24 kg) were included. There was no significant difference in mean TTP (in seconds) at baseline (4.23) as compared to the second (3.90), third (4.41), fourth (4.60), and fifth ICG assessment (5.99). As a result of ICG accumulation, the mean and the maximum absolute fluorescence intensity were significantly different as compared to the baseline assessment. There was no significant difference in LCL levels (in mmol/L) at baseline (0.74) as compared to the second (0.82), third (0.64), fourth (0.60), and fifth assessment (0.62). Increasing doses of norepinephrine infusion have no significant influence on bowel perfusion using ICG fluorescence angiography.

Quantification of indocyanine green near-infrared fluorescence bowel perfusion assessment in colorectal surgery

“…Thus, there might be a risk of random sampling errors. Additionally, variation in patient-specific hemodynamic factors or the use of vasopressors during the ICG NIR fluorescence measurement could affect the observed perfusion pattern which requires further evaluation because of limited evidence in literature [ 32 ]. Second, our standardized imaging protocol only allows for extracorporeal video recordings of the ICG NIR fluorescence bowel perfusion assessment.…”

Clinical application of machine learning and computer vision to indocyanine green quantification for dynamic intraoperative tissue characterisation: how to do it

“…Previous work has demonstrated discrepancies in detected fluorescence intensities with ICG circulation (related to both dosing amount and methods as well as patient and anaesthesia-related variables) and further vary by on-screen tissue location (e.g. near vs far, centre vs periphery) [ 16 – 18 ]. Other potential pitfalls for interpretation by both humans and machines include the clinically observed phenomenon of ICG tissue diffusion vs true perfusion and the fact that rectal tumours can contain areas of admixed malignant and benign disease.…”

Experimental evaluation of laparoscopic laser speckle contrast imaging to visualize perfusion deficits during intestinal surgery

“…As a result, intraoperative assessment of bowel perfusion is a vital element in surgical decision-making when performing restorative intestinal resections [ 6 ]. However, the traditional direct visual inspection of the intestinal tissue for signs of viability (e.g., mucosal color, pulsatile bleeding from marginal arteries) is highly subjective and does not allow for an adequate evaluation of intestinal microperfusion [ 6 – 8 ]. For this reason, numerous techniques, such as near-infrared fluorescence angiography and the assessment of various parameters of intestinal viability have recently been developed.…”