In-Situ Hemodynamics and Oxygen Utilization in Right Lobe Grafts During Living Donor Hepatectomy

Abstract

Background

Several studies have examined liver graft hemodynamics during living donor liver transplants; however, to the best of our knowledge, the hemodynamics of the partial graft during donor hepatectomy have not been thoroughly explored. We analyzed intraoperative graft hemodynamics and oxygen utilization data following parenchymal dissection during living donor hepatectomy.

Methods

The following parameters were measured intraoperatively in 63 right hepatic lobe living donor hepatectomy cases: right portal vein (RPV) and right hepatic artery (RHA) blood flow after parenchymal transection, along with blood gas analysis from the RPV, RHA, and right hepatic vein. Using these flow and blood gas analysis data, oxygen delivery and oxygen consumption of the right lobe graft were calculated and analyzed.

Results

A significant decrease in graft weight-normalized RHA flow was observed as the portal vein gradient increased, while graft weight-normalized RPV flow remained relatively constant. No differences in weight-normalized flow or blood gas data were observed between male and female donors. However, donors aged 40 years and older exhibited a statistically significant reduction in graft weight-normalized RHA oxygen delivery compared to younger donors (P = .042).

Conclusions

High portal pressure and donor age are known risk factors for small-for-size syndrome in living donor liver transplantation. Our data showed that even a relatively small increase in portal vein gradient significantly reduces RHA flow, negatively affecting oxygen delivery. This suggests that right lobe grafts may be prone to ischemic injury, especially in recipients with a low graft-to-recipient weight ratio from older donors.