Abstract
Evaluation of intestinal perfusion remains subjective and depends on the surgeon´s individual experience. Intraoperative quality assessment of tissue perfusion with indocyanine green (ICG) fluorescence using a near-infrared camera system has been described in different ways and for different indications. The aim of the present study was to evaluate fluorescent imaging (FI) in the quantitative assessment of intestinal perfusion in a gastric tube model in pigs and to compare the results to results obtained with florescent microspheres (FM), the gold standard for tissue perfusion. Seven pigs (56.0±3.0 kg), both males and females, underwent gastric tube formation after transection and ligation of the gastric arteries, except the right gastroepiploic artery, to avoid collateral blood flow. After baseline assessment (T0), hypotension (T1) was induced by propofol (Karampinis et al 2017) (< 60 mmHg). Then, propofol was paused to obtain normotension (T2, Mean arterial pressure (MAP) 60-90 mmHg). Finally, hypertension (T3, MAP>90 mmHg) was induced by norepinephrine. Measurements were performed in three regions of interest (ROIs) under standardized conditions: the fundus (D1), corpus (D2), and prepyloric area (D3). Hemodynamic parameters and transit-time flow measurement (TTFM) in the right gastroepiploic artery were continuously assessed. FI, FM and the partial pressure of tissue oxygen (TpO2) were quantified in each ROI. The study protocol could successfully be performed during stable hemodynamics. Flow in the gastroepiploic artery measured by transit time flow measurement (TTFM) was related to hemodynamic changes between the measurements, indicating improved blood flow with increasing MAP. The distal part of the gastric tube (D1) showed significantly (p<0.05) impaired perfusion compared to the proximal parts D3 and D2 using FM. ICG-FI also showed the highest values in D3 and the lowest values in D1 at all hemodynamic levels (T1-T3; p<0,05). Visual and quantitative assessment of gastric tube perfusion is feasible in an experimental setting using ICG-FI. This might be a promising tool for intraoperative assessment during visceral surgery in the future.
Highlights
The assessment of organ perfusion is a crucial step in several types of visceral surgery, such as esophagectomy, colonic resection, and surgery for mesenteric ischemia
Flow in the gastroepiploic artery measured by transit time flow measurement (TTFM) was related to hemodynamic changes between the measurements, indicating improved blood flow with increasing MAP
Indocyanine green (ICG)-fluorescent imaging (FI) showed the highest values in D3 and the lowest values in D1 at all hemodynamic levels (T1T3; p
Summary
The assessment of organ perfusion is a crucial step in several types of visceral surgery, such as esophagectomy, colonic resection, and surgery for mesenteric ischemia. Independent and quantitative methods to gage visceral perfusion are of mixed effectiveness. It is a safe fluorescent dye that has been used for decades in the measurement of liver function, via ICG clearance, and microcirculation and in ophthalmic angiography. It is quickly and completely eliminated by the liver with a half-life of 2.4 minutes, which allows multiple applications. Because of its user-friendly properties, FI has enjoyed growing popularity in the assessment of tissue perfusion during surgery due to its suspected influence on anastomotic healing [6, 7]. The advantage of using ICG-FI in daily routine practice is currently uncertain [7]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
