Introduction: We aimed to assess the performance of red blood cell distribution width (RDW) and all platelet indices to predict clinical outcomes in pediatric intensive care units (PICUs).
Materials and Methods: We analyzed 99 critically ill pediatric patient admitted to PICU. The power of RDW and platelet indices in mortality prediction were assessed and compared to the power of the Pediatric Index of mortality (PIM 3) using Receiver operating characteristic curve (ROC). Potential mortality predictors were identified and analyzed using multivariable logistic regression.
Results: RDW, platelet counts and platelet indices ratios independently predicted PICU mortality. RDWCV showed OR of 10.3 which was significant (p = 0.001) and AUC of 0.706 with 95% CI ranging from 0.603 to 0.808. Best cut off point was 14% at which sensitivity and specificity were 94.6% and 37.1% respectively. PIM 3 score yielded AUC of 0.74 which was not significantly different to that of RDW. This score predicted mortality, in our population was 6.644 %, higher than the mortality predicted in the regions where the model was developed. Thrombocytopenia was associated with higher rates of mortality (p= 0.002), with a best cutoff at 190 x 103 cells/μL. MPV and PDW values showed no significant difference between survivors and non survivors (p= 0.158, p= 0.9) respectively. Platelet ratios (MPV/PCT, MPV/PC, PDW/PCT, PDW /PC) were better predictors of mortality than platelet indices by themselves. All the ratios of platelet indices were statistically significant (p-value < 0.05).
Conclusions: In pediatric critically ill patients, RDW and platelet indices ratios
could serve as independent predictors of PICU mortality.
Keywords: Red cell distribution width, Platelet indices, Pediatric index of mortality, Critical illness, Mortality
Abbreviations
RDWCV: Red cell distribution width coefficient variant; PICUs: Pediatric intensive care units; OR: Odds ratio; ROC: Receiver operating characteristic; AUC: Area under the curve; 95% CI: Confidence interval; PIM-3: Third generation pediatric index of mortality; MPV: Mean platelet volume; PDW: Platelet differential width; PCT: plateletcrit; PC: Platelet count. |
