Effect of post-perfusion hyperoxemia on early graft function in renal transplant recipients: a retrospective observational cohort study.

Abstract

The effects of hyperoxemia on the transplanted grafts arouse interest nowadays, particularly intraoperative hyperoxemia, on transplant kidney function and survival in the 1-year post-operative period. We aimed to investigate the effect of post-perfusion (5 min after perfusion) hyperoxemia on early graft function and survival in renal transplant recipients. Two hundred forty-seven living donor kidney transplant recipients were included in the study. Patients were divided into the three groups according to their partial arterial oxygen pressure in post-perfusion blood gas samples: group 1: normoxia (n = 52, PaO2 pressure: < 120 mmHg, 103 ± 13); group 2: moderate hyperoxemia (n = 121, PaO2: 120-200 mmHg, 169 ± 21); group 3: severe hyperoxemia (n = 74, PaO2: > 200 mmHg, 233 ± 25). Graft functions (serum creatinine levels, estimated-glomerular filtration rate values, spot urine protein/creatinine ratio), survival rates, and groups' clinical outcomes were compared in the first year after transplantation. Graft survival rates were similar in the groups and the rate of BK virus viremia was the lowest in the group 3 (groups 1, 2, and 3: 15.4% (n = 8), 6.6% (n = 8), 1.4% (n = 1), respectively, P: 0.009). Serum creatinine and proteinuria levels were lower, and estimated-glomerular filtration rate values were higher in group 3. A negative correlation between partial arterial oxygen pressure and serum creatinine levels and a positive correlation with estimated-glomerular filtration rate value were noted. These results were confirmed by univariate and multivariate analyses. We demonstrated that the kidney transplant recipients with post-perfusion hyperoxemia have better early graft functions and lower BK virus viremia rates. ClinicalTrials.gov Identifier: NCT04420897.