Managing Expectations of Prolonged Warm Ischemia Time: A Calculator to Predict Donation After Circulatory Death Donor Progression to Circulatory Death Within 30 Min

BACKGROUND: Transplant teams may be better prepared to entertain DCD offers with a priori prediction of prolonged warm ischemia time (WIT) and deploy perfusion strategies (PS) to mitigate the risk of WIT. METHODS: All potential adult Maastricht-III DCDs in one Organ Procurement Organization from January 2016 to July 2024 were reviewed. Data were obtained from UNOS DonorNet. Cases with missing variables were excluded. The most recent clinical values prior to withdrawal of life support treatment (WLST) were utilized. Logistic regression assessed the likelihood of DCD progression within 30 min after WLST. RESULTS: From a total of 748 potential DCDs, 350 were assessed after exclusion criteria. One hundred and seventy-one (49%) progressed within 30 min. Forty percent (n = 140) of the sample was used for training and 60% (n = 160) for validation. Potassium (OR: 3.01; 95% CI: [1.39, 6.5], p = 0.005), sodium (OR: 1.23; 95% CI: [1.01, 1.50], p = 0.036); body mass index (OR: 1.68; 95% CI: [1.39, 2.03], p = 0.0001) and heart rate (OR: 1.54; 95% CI: [1.24, 1.92], p = 0.0001) positively correlated with progression. Age (OR: 0.71; 95% CI: [0.58, 0.86], p = 0.0006); presence of pupillary reflexes (OR: 0.81; 95% CI:[0.68, 0.92], p = 0.007); presence of corneal reflexes (OR: 0.27; 95% CI: [0.22, 0.34], p = 0.001); and presence of overbreathing the ventilator (OR: 0.39; 95% CI: [0.32, 0.48], p = 0.001) negatively correlated with progression. Discrimination was excellent (NPV 89%; PPV 88%). CONCLUSIONS: DonorNet variables predict progression to circulatory death within 30 min. If there is an indication that a DCD will not progress within a 30-min threshold, then early discussion of PS may decrease the risk of a dry run.