Evaluating the Impact of Cardiopulmonary Bypass Priming Fluids on Bleeding After Pediatric Cardiac Surgery: A Systematic Review and Meta-Analysis.

OBJECTIVES: Cardiopulmonary bypass (CPB) predisposes young children to coagulopathy. The authors evaluated possible effects of CPB priming fluids on perioperative bleeding in pediatric cardiac surgery. DESIGN: Meta-analysis and systematic review of previously published studies. SETTING: Each study was conducted in a surgical center or intensive care unit. PARTICIPANTS: Studies investigating patients <18 years without underlying hematologic disorders were included. INTERVENTIONS: The authors evaluated randomized controlled trials (RCTs) published between 1980 and 2020 on MEDLINE, EMBASE, PubMed, and CENTRAL databases. The primary outcome was postoperative bleeding; secondary endpoints included blood product transfusion, mortality, and safety. MEASUREMENTS AND MAIN RESULTS: Twenty eligible RCTs were analyzed, with a total of 1,550 patients and a median of 66 patients per study (range 20-200). The most frequently assessed intervention was adding fresh frozen plasma (FFP) to the prime (8/20), followed by albumin (5/20), artificial colloids (5/20), and blood-based priming solutions (3/20). Ten studies with 771 patients evaluated blood loss at 24 hours in mL/kg and were included in a meta-analysis. Most of them investigated the addition of FFP to the priming fluid (7/10). No significant difference was found between intervention and control groups, with a mean difference of -0.13 (-2.61 to 2.34), p = 0.92, I2 = 69%. Further study endpoints were described but their reporting was too heterogeneous to be quantitatively analyzed. CONCLUSIONS: This systematic review of current evidence did not show an effect of different CPB priming solutions on 24-hour blood loss. The analysis was limited by heterogeneity within the dataset regarding population, type of intervention, dosing, and the chosen comparator, compromising any conclusions.