Retrograde autologous priming (RAP) has been routinely applied in cardiac pediatric cardiopulmonary bypass (CPB). However, this technique is performed in pediatric patients weighing more than 20 kg, and research about its application in pediatric patients weighing less than 20 kg is still scarce. This study explored the clinical application of RAP in CPB in pediatric patients undergoing cardiac surgery. Sixty pediatric patients scheduled for cardiac surgery were randomly divided into control and experimental groups. The experimental group was treated with CPB using RAP, while the control group was treated with conventional CPB (priming with suspended red blood cells, plasma and albumin). The hematocrit (Hct) and lactate (Lac) levels at different perioperative time-points, mechanical ventilation time, hospitalization duration, and intraoperative and postoperative blood usage were recorded. Results Results Overall treatment outcome One case in the experimental group was excluded because the operation time was longer than 120 min. All patients of the experimental group completed RAP, and only 2 patients were administrated desoxyepinephrine for unstable blood pressure. The experimental group significantly reduced priming amount, and 17 patients had no allogeneic blood transfusion perioperatively, while 26 patients of the control group received allogeneic blood transfusion. All patients were discharged successfully, and exhibited no blood transfusion-induced complications during hospitalization. Comparison of general information There were no significant differences in gender, age, body weight or other general information between two groups (P>0.05). Furthermore, the preoperative Lac, creatinine, urea nitrogen, left ventricular ejection fraction (LVEF) and Hct levels between the two groups showed no significant difference (P>0.05; Table 1). Comparison of intraoperative indicators There were no significant differences of CPB time, aortic blocking time, T2-Lac or T3-Lac between the two groups (P>0.05). However, the T2-Hct and T3-Hct values, and intraoperative blood transfusion exhibited significant differences between the two groups (P<0.05; Table 2). Hct levels in the experimental group were lower than those in the control group, but still maintained at >0.25 (except in two cases), which met the requirement for intraoperative blood management (Hct >0.25). In addition, the blood gas results were normal, and there was no difference in oxygen metabolism between the two groups, indicating that hemodynamics was stable during CPB in both groups. In order to further improve the Hct level (the target being >0.27), the modified ultrafiltration was performed in both groups. According to the residual blood volume in CPB circuit, the ultrafiltration volume was set as 300-450 mL. Postoperative indicators There was no significant difference in T4-Hct value, mechanical ventilation time, ICU time, hospitalization duration or postoperative blood transfusion between the two groups (P>0.05; Table 3). At 2h postoperative, Hct levels in experimental group were higher than the control group, but the difference was not significant. showed that Hct levels at 15 min after CPB beginning (T2) and at CPB end (T3), and number of intraoperative blood transfusions were significantly lower in the experimental group (P<0.05). There were no significant differences in CPB time, aortic blocking time, T2-Lac value or T3-Lac between the two groups (P>0.05). Postoperatively, there were no significant differences in Hct (2 h after surgery), mechanical ventilation time, intensive care unit time, or postoperative blood transfusion between two groups (P>0.05). RAP can effectively reduce the hemodilution when using less or not using any banked blood, while meeting the intraoperative perfusion conditions, and decreasing the perioperative blood transfusion volume in pediatric patients.
Cardiopulmonary bypass; Retrograde autologous priming; Cardiac surgery
