Comparable prognosis in different neonatal histidine-tryptophan-ketoglutarate dosage management

Background:Histidine-tryptophan-ketoglutarate(HTK)is a solution commonly used for organ transplantation.However,there is no certified fixed regimen for on-pump heart surgery in neonates.We aimed to retrospectively evaluate the outcomes related to different HTK dosages and to analyze the safety of high-dosage perfusion.Methods:A total of 146 neonates who underwent on-pump heart surgery with single-shot HTK perfusion were divided into two groups according to HTK dosages:a standard-dose(SD)group(n=63,40 mL/kg<HTK≤60 mL/kg)and a high-dose(HD)group(n=83,HTK>60 mL/kg).Propensity score matching(PSM)was performed to control confounding bias.Results:The SD group had a higher weight(3.7±0.4 vs.3.4±0.4 kg,P<0.0001),a lower proportion of complete transposition of the great artery(69.8%vs.85.5%,P=0.022),a lower cardiopulmonary bypass(CPB)time(123.5[108.0,136.0]vs.132.5[114.8,152.5]min,P=0.034),and a lower aortic x-clamp time(82.9±27.1 vs.95.5±26.0 min,P=0.005).After PSM,44 patients were assigned to each group;baseline characteristics and CPB parameters between the two groups were comparable.There were no significant differences in peri-CPB blood product consumption after PSM(P>0.05).The incidences of post-operative complications were not significantly different between the two groups.There were no significant differences in ventilation time,intensive care unit stay,and post-operative hospital stay(P>0.05).Follow-up echocardiography outcomes at 1 month,3 to 6 months,and 1 year showed that left ventricular ejection fraction and end-diastolic dimension were comparable between the two groups.Conclusions:In neonatal on-pump cardiac surgery patients,single-shot HD(>60 mL/kg)HTK perfusion had a comparable heart protection effect and short-term post-operative prognosis as standard dosage perfusion of 40 to 60 mL/kg.Thus,this study provides supporting evidence of the safety of HD HTK perfusion.