Effect of single-dose crystalloid cardioplegic agent compared to bloody cardioplegic agent in cardiac surgery in children with Tetralogy of Fallot

Cardioplegia is one of the main post-operative cardiac protective factors widely used in recent decades in the form of crystalloid (St. Thomas) and bloody solutions [del Nido (DN)]. The purpose of this study was to compare the effect of a crystalloid cardioplegic agent (St. Thomas) with that of a bloody cardioplegic agent (DN) in pediatric cardiac surgery among children with Tetralogy of Fallot (TOF).

This study was performed on 60 children with TOF, who were candidates for heart repair surgery. The participants were randomly divided into two groups of crystalloid cardioplegic agent and bloody cardioplegic agent. Operative outcomes such as required time for onset of heart arrest, duration of returning to normal heart rhythm, and cardiopulmonary bypass (CPB) time, and operative complications were compared between the two groups.

The duration of returning to normal heart rhythm (50.43 ± 10.93 seconds vs. 43.03 ± 16.35 seconds; P = 0.044) and duration of inotropy (80.40 ± 27.14 hours vs. 63.20 ± 26.91 hours; P = 0.017) were significantly higher in the DN group compared to the St. Thomas group. However, there were no significant differences between the two groups in terms of heart arrest time, cross-clamp time, CPB time, supplementary lasix time, duration of intubation, and intensive care unit (ICU) and hospital length of stay (LOS) (P > 0.050).

The use of St. Thomas cardioplegic solution was more effective in reducing the duration of returning to normal heart rhythm and inotropy compared with DN cardioplegic agent, and a single dose of these two cardioplegic agents can keep the mean cardiac arrest duration within the range of 50-70 minutes. It seems that the use of St. Thomas cardioplegic solution can be suggested in pediatric heart surgery.