Cardioplegia strategy and perioperative blood transfusion in isolated coronary artery bypass surgery: a propensity-weighted analysis.

BACKGROUND

Del Nido cardioplegia has been increasingly adopted in adult cardiac surgery due to its single-dose administration and simplified myocardial protection strategy. However, concerns persist regarding its relatively high crystalloid content and the potential for increased hemodilution and blood transfusion. This study aimed to compare transfusion requirements and early clinical outcomes between del Nido and conventional multidose blood cardioplegia in patients undergoing isolated coronary artery bypass grafting (CABG).

METHODS

In this retrospective single-center study, 405 consecutive patients undergoing isolated on-pump CABG were analyzed. Patients were grouped according to cardioplegia strategy: del Nido (n = 319) or conventional blood cardioplegia (n = 86). The primary outcome was perioperative packed red blood cell (PRBC) transfusion. Secondary analyses compared early clinical recovery directly between the cardioplegia strategies. Multivariable logistic regression and propensity score-based inverse probability of treatment weighting (IPTW) were performed to adjust for baseline and operative variables, strictly excluding cases of non-cardioplegia-related mechanical bleeding to refine the analytical models.

RESULTS

Del Nido cardioplegia was associated with higher rates of zero transfusion (27.9% vs. 17.4%, p = 0.020) and lower rates of massive transfusion (≥ 4 units: 23.8% vs. 36.0%). While multivariable adjustment yielded a borderline association for any transfusion (aOR 0.54, 95% CI 0.26-1.05; p = 0.082) largely driven by operative times, propensity-weighted analyses suggested lower odds of any transfusion with del Nido (OR 0.48, 95% CI 0.24-0.95; p = 0.035). Ordinal regression further demonstrated a significant reduction in transfused blood volume (adjusted Coef = -0.508; p = 0.023). Postoperative 24-hour chest tube drainage was identical between groups (median 600 mL vs. 600 mL; p = 0.845). Clinically, the del Nido group demonstrated a significantly shorter duration of mechanical ventilation compared to the blood cardioplegia group (median 7.0 vs. 8.0 h; p = 0.029), while median hospital length of stay was 6.0 versus 5.0 days (p = 0.001).

CONCLUSIONS

Del Nido cardioplegia was not associated with increased transfusion requirements in isolated CABG surgery and may offer a modest transfusion-sparing effect when baseline patient characteristics are balanced. Operative complexity remains a major determinant of perioperative blood utilization. Prospective studies are warranted to further clarify the relationship between cardioplegia strategies and transfusion outcomes.