Scavenging right atrial Bretschneider histidine-tryptophan-ketoglutarate cardioplegia: Impact on hyponatremia and seizures in pediatric cardiac surgery patients

Objective: Custodiol-HTK cardioplegia (Custodiol-HTK Koheler Chemie, GmbH, Bensheim, Germany) causes fluctuations in serum sodium levels, hyponatremia, and is associated with postoperative seizures. We investigated the influence of scavenging right atrial effluent during delivery on intraoperative serum sodium levels and postoperative seizure incidence in pediatric cardiac surgery patients. Methods: A total of 204 patients younger than age 18 years undergoing congenital heart surgery between January 2016 and March 2018 were analyzed retrospectively. Serum sodium levels after administration of Custodiol-HTK cardioplegia were compared between the scavenge and nonscavenge groups and then in the propensity score-matched cohort (n = 96). Postoperative seizures were documented clinically and with electroencephalogram findings. Logistic regression models were used to identify the independent predictors of serum sodium level after aortic crossclamp. Results: Of 204 patients, 156 (76.5%) were in the nonscavenge, and 48 (23.5%) in the scavenge groups. A serum sodium level <130 mEq/L after crossclamp and administration of Custodiol-HTK cardioplegia in the nonscavenge group were 70% versus 21% in the scavenge group (odds ratio, 8.8; 95% confidence interval, 4.1-18.3; P < .0001) in the entire cohort, and 77% versus 21% (odds ratio, 12.8; 95% confidence interval, 4.8-33.1; P < .0001) in the propensity score-matched cohort. Of 16 patients experiencing a postoperative seizure, 14 (87.5%) had a sodium level <130 mEq/L and 2 (12.5%) had a sodium level =130 mEq/L (odds ratio, 5.1; 95% confidence interval, 1.3-22.8; P = .021) after crossclamp. Postoperative seizures occurred in the nonscavenge group but not the scavenge group in the entire cohort (P = .02) and in the propensity score-matched patients (P = .041). Multivariable analysis of the entire cohort showed that scavenge intervention was an independent factor associated with significantly decreased risk of sodium level <130 mEq/L (odds ratio, 0.17; 95% confidence interval, 0.08-0.36; P = .000). Conclusions: Right atrial effluent scavenging was protective against fluctuations in serum sodium levels after crossclamp and Custodiol-HTK cardioplegia administration independently in both entire and matched cohort, and was also associated with decreased incidence of postoperative seizures.