Association Between Elevated RBC Distribution Width and Multiple Organ Dysfunction in Pediatric Critical Illness

Objectives: RBC distribution width, a part of the complete blood count, has been shown in several published studies to be a strong biomarker of adverse outcomes. We sought to determine the association between admission RBC distribution width value and clinical outcomes including multiple organ dysfunction, mechanical ventilation days, PICU length of stay, and hospital length of stay in children admitted to the PICU. Design: Single center, retrospective study. Setting: A tertiary pediatric hospital in the United States. Patients: All subjects admitted to the PICU from 2016 to 2017. Exclusions: Greater than 21 years old, pregnancy, and history of packed RBC transfusion within 120 days prior to admission. Interventions: None. Measurements and Main Results: One-thousand five-hundred one subjects were screened and 856 were included in data analysis. RBC distribution width value was categorized into four separate groups: group I (RBC distribution width < 13.4%), group II (13.4-14.3%), group III (14.4-15.7%), and group IV (RBC distribution width > 15.7%). Increased RBC distribution width at admission was associated with multiple organ dysfunction syndrome in the first 7 days (group I = 11.8% vs group IV = 30.1%; p < 0.0001) (odds ratio, 3.22; 95% CI, 1.95-5.30; p < 0.0001). Increased RBC distribution width was associated with increased median mechanical ventilation duration (group IV = 7 d vs group I = 5 d; p = 0.001), median hospital length of stay (group IV = 13 d vs group I = 5 d; p < 0.0001), and median PICU length of stay (group IV = 4 d vs group I = 3 d; p = 0.01). Mortality was not statistically associated with admission RBC distribution width (p = 0.12). Conclusions: PICU admission RBC distribution width values greater than 15.7% obtained upon admission to the PICU in patients who have not received a RBC transfusion are associated with multiple organ dysfunction syndrome in the first 7 days of admission, increased duration of mechanical ventilation, and increased hospital length of stay.