Red Blood Cell Distribution Width as a Predictive Biomarker for Postoperative Infections in Children Who Underwent Cardiac Surgery: A Single-Center Retrospective Study

Background It has been investigated that red blood cell distribution width (RDW) is associated with the clinical outcomes of patients following surgeries and is used as a prognostic biomarker for postsurgical complications. In this study, we aimed to assess the value of RDW as a predictor of postoperative complications in children after cardiac surgeries. Methods Three hundred fifty-five pediatric patients who underwent cardiac surgery between 2017 and 2018 were enrolled, and preoperative and postoperative RDW values were determined. Data collected included demographics; incidence of postsurgical complications, including sepsis, surgical site infections (SSIs), urinary tract infections (UTIs), and ventilator-associated pneumonia (VAP); length of hospital and pediatric cardiac intensive care unit (PCICU) stay; and ventilator duration. Results Among children who underwent cardiac surgery, 29 (8.2%) of the cases developed bloodstream infections (BSIs), while urinary tract infections (UTIs) were observed in 32 (9.0%) of the cases, and ventilator-associated pneumonia (VAP) was observed in 36 of the cases (10.1%). Of all cases, surgical site infections (SSIs) were reported in 13 patients (3.7%). Significantly higher postoperative RDW levels were observed on days three (p-value=0.028), five (p-value=0.041), and seven (p-value=0.042) in cases of BSI. For UTI cases, only preoperative RDW levels (p<0.001) and postoperative day three RDW levels (p<0.049) were significantly higher than their counterparts. VAP cases had significantly higher RDW levels pre-operatively (p-value=0.002), which was also observed in postoperative RDW levels on days three (p-value=0.033), five (p-value=0.031), and seven (p-value=0.021) in comparison to their analogs (p-values<0.05). Furthermore, a significant relationship was found between preoperative RDW and length of intensive care unit (ICU) stay (95% CI 0.685-3.221, p-value=0.003, R2=0.104) and duration of mechanical ventilation (95% CI 0.549-1.938, p-value=0.001, R2=0.102). Conclusion RDW is a significant factor in predicting complications in pediatric patients' post-cardiac surgeries, including BSI, UTI, and VAP, which would consequently anticipate patients' clinical state after cardiac procedures.