Case Studies
Case studies showcase real-world applications of policies and innovations, offering insights into improving outcomes and efficiency. They enhance problem-solving skills, highlight best practices, and engage through storytelling for education and transparency.
Extended Pump Cold Ischemia Time is a Predictor for Liver Failure on Normothermic Machine Perfusion
Ronald
Squires
, MD
, Chief Medical Officer
, LifeShare Oklahoma
The Challenge
8-12 hours of transplant cold ischemia time (TCIT, which is the time from cold perfusion of graft until the removal of the graft from ice to be implanted), is generally considered acceptable for successful liver transplantation (LT). This study evaluates the impact of pump cold ischemic time (PCIT, which is the time from cold perfusion of the graft to initiation of perfusate flow on the normothermic machine perfusion (NMP)) on the risk for liver allograft failure following NMP.
The Approach
112 suboptimal donor livers (high body mass index (BMI), donation after circulatory death (DCD) donor, macrovascular steatotic livers, age & gt; 60) were placed on OrganOx metra® NMP to assess functional suitability for transplantation (Table 1).
The Results
After 4-16 h of perfusion, 88 (78.6%) of grafts with acceptable NMP parameters (lactate clearance, production and quality of bile, glucose metabolism and pH) were transplanted successfully. 24 (21.4%) were discarded due to unacceptable parameters (Table 1).
19 of 21 (90.5%) BD and 69 of 91 (75.8%) DCD livers had acceptable perfusion parameters and were transplanted successfully (Table 2). DCD livers, with functional warm ischemia time (systolic pressure & lt; 80 mmHg to crossing time) & lt; 30 mins were no less likely to be utilized compared to brain death (BD) livers in this study (P & gt; 0.05).
13 of 37 (35.1%) livers with PCIT & gt; 4.0 hours and 11 of 75 (14.7%) livers with PCIT & lt; 4.0 hours had unacceptable perfusion parameters and were discarded (Table 2). Livers experiencing PCIT & gt; 4 hours were 2.4 times more likely to have poor metabolic parameters and be discarded (p & lt; 0.05).
Insights & Lessons Learned
Longer PCIT is associated with a significantly higher incidence of metabolic dysfunction and non-utilization as compared to livers experiencing less than 4 hours of PCIT. This data suggests an advantage to onsite cannulation and initiation of NMP in the operative theater over a back to base model in order to lessen PCIT.