Effect of retrograde autologous priming based on miniaturized cardiopulmonary bypass in children undergoing open heart surgery: A STROBE compliant retrospective observational study

To evaluate the effectiveness of retrograde autologous priming (RAP) based on miniaturized cardiopulmonary bypass (CPB) circuit in children undergoing open heart surgery. We performed a retrospective analysis of all patients (≤15 kg) who underwent open heart surgery with CPB in our center from January 1, 2017, to July 31, 2019. Propensity score matching was used to adjust for significant covariates, and multivariable stratified analysis was used to assess the association of the RAP technique with clinical outcomes. A total of 1111 patients were analyzed. There were 355 (32.0%) children who underwent RAP, and 756 (68.0%) were in the non-RAP group. After propensity score matching, there were a total of 638 patients, with 319 patients in each group. The bloodless priming rate was significantly higher (P = .013), and the ultrafiltration rate was significantly lower (P = .003) in the RAP group than in the non-RAP group. Compared with patients in the non-RAP group, patients in the RAP group had a shorter postoperative mechanical ventilation time (P < .001) and shorter lengths of stay in the intensive care unit (ICU) (P < .001) and the hospital (P < .001). No differences were noted in postoperative hematocrit (P = .920), postoperative 24-hour blood loss (P = .435), and hospital mortality (P = .563). In the stratified analysis, the difference remained statistically significant (P < .05) when the patient weight was >4 kg or the Society of Thoracic Surgeons-European Association for Cardiothoracic Surgery (STAT) category was <3. However, when the patient weight was ≤4 kg or the STAT category was ≥3, there was no significant difference between the 2 groups in terms of bloodless priming, ultrafiltration, postoperative mechanical ventilation time, or length of stay in the ICU or the hospital (P > .05). The RAP technique based on miniaturized CPB system was safe and effective for children who underwent congenital heart surgery. The RAP technique can significantly reduce the priming volume, improve the rate of bloodless priming, and reduce blood product application. It was also associated with a shorter postoperative mechanical ventilation time and shorter lengths of stay in the ICU and the hospital.