Hemoglobin/Red Cell Distribution width Ratio (HRR): A Novel and Promising Red Cell Parameter in Ductal Closure

Abstract Background It is still unclear how effective hematological parameters are in the closure of patent ductus arteriosus (PDA). Objectives The primary aim of our study is to investigate the effect of hemoglobin (HB)-to-red cell distribution width (RDW) ratio (HRR) on the closure of PDA. Methods Premature babies with very low birth weight (VLBW: <1500 g) and <32 gestational weeks were included in the study, and all data were recorded retrospectively. Demographic characteristics, clinical results, red cell parameters, and HRR and their ratios were compared between hemodynamically significant PDA (hsPDA) and non-hsPDA groups. All results were statically analyzed, and P<0.05 was considered statistically significant. Results A total of 677 premature babies, 269 in the hsPDA group and 408 in the non-hsPDA group, were included in the study. Hemoglobin (HB), hematocrit (HCT), mean cell volume (MCV), red blood cell (RBC), red cell distribution width (RDW), mean platelet volume (MPV), MCV/RBC ratio, HB/RBC ratio, RDW/RBC ratio, and RDW/MPV ratio were found to be similar between hsPDA and non-hsPDA groups, (p>0.05). HRR was found to be significantly lower in the hsPDA group [median (Quartile 1 (Q1) - Q3) (Q1 - Q3): 0.93 (0.8-1.0)] compared to non-hsPDA [median ( Q1 - Q3): 1.07 (1.0-1.2)] (p<0.001). The AUC for the diagnostic value of HRR in hsPDA was 0.816, and the cutoff value was ≤0.98 (p<0.001, 95% [CI]: 0.785-0.845, sensitivity: 90%, specificity: 92%). Conclusions HRR value was found to be both an effective and powerful parameter in diagnosing hsPDA.