L. Dongur1, C. Chavez1, J. Martella1, M. Johnson1, S. Samreen1, J. Moffett1 1UTMB, Galveston, TEXAS, USA
The critical view of safety is integral to a successful cholecystectomy. Indocyanine Green (ICG) is a helpful adjunct in minimally invasive cholecystectomies. ICG, a water-soluble substance, is intravenously administered up to a maximal dose of 2 mg/kg with a standard concentration of 2.5mg per 1 ml. Based on data from Intuitive, it is recommended to administer 2.5 mg of ICG at least 45 minutes prior to incision time. However, this is based on patients with biliary colic undergoing elective cholecystectomies. Currently, there are no recommendations for optimal ICG administration time in patients with inflammatory cholecystitis. Our study reviewed retrospective data from January 2020 to July 2022 of adult patients who underwent laparoscopic assisted robotic cholecystectomy. Primary outcomes included visualization of both Cystic Duct (CD) and Common Bile Duct (CBD), which were assessed from intraoperative (IO) videos that were reviewed by two independent blinded surgeons. Secondary outcomes included IO CBD injury and total operative time (OT). Our final cohort of patients after our exclusion process resulted in 41 patients. Upon review of reported post operative diagnosis, 19% (n = 8) had Acute Cholecystitis (AC), 36% (n = 15) had Chronic Cholecystitis (CC), 44% (n = 18) had other (OTH) diagnosis (i.e., biliary colic, choledocholithiasis, and gallstone pancreatitis). Final pathology reports demonstrated 12% (n = 5) had AC, 17% had Acute on Chronic Cholecystitis (ACC), 73% had CC. Initial analysis was performed using Fischer Exact Test by categorizing total ICG time into under 45 minutes, between 45 minutes to 180 minutes, over 180 minutes. There were no patients with CBD injury. Overall, there was a statistically significant relation between CD visualization and ICG administration (p-value = 0.02) but there was no significance noted for CBD visualization (p-value = 0.11). Furthermore, there was no statistically significant relation between ICG administration time and visualization of either CD or CBD in patients with histopathological diagnosis of AC and ACC (p-value = 1 for both). However, there was statistically significant relation between ICG administration time and both CD and CBD visualization in patients with CC (p-value = 0.0025 for both). Within sub-cohorts of patients with or without CBD and/or CD visualization, linear regression analysis showed that there was no significant correlation between either CBD or CD visualization based on ICG time. No significant relation was noted between OT and ICG time within groups of AC, CC, and OTH (p-value of 0.65, 0.24, and 0.16 respectively). Overall OT and ICG time were not strongly correlated (r = 0.07, p-value of 0.65). The power of the study is reduced due to the small sample size. With an updated cohort in the future, we hope to strengthen our results. While the utility of ICG is established, there is still more research needed to standardize diagnosis driven usage of ICG.