Initial Modified Pulmonary Index Score Predicts Hospital Length of Stay for Asthma Subjects Admitted to the Pediatric Intensive Care Unit

Abstract

Background: Scoring systems are frequently used to assess the severity of pediatric asthma exacerbations. The modified pulmonary index score (MPIS) has been found to be highly correlated with length of stay (LOS) in the pediatric intensive care unit (PICU). We sought to evaluate the use of the MPIS to predict hospital LOS for patients admitted to our PICU.

Methods: We retrospectively reviewed the medical records of pediatric asthma subjects aged 2-17 y admitted to our PICU between June 2014 and November 2017. We divided subjects a priori into 3 groups (low: MPIS 0-5; medium: MPIS 6-9; high: MPIS ≥ 10) based upon each subject's first MPIS documented in the PICU. Hospital LOS, PICU LOS, time on continuous albuterol, and increased respiratory support were compared between groups.

Results: 143 subjects were included. There were no differences for demographics, medical history, cause of exacerbations, or mean heart rate between groups. There were significant differences between groups for mean breathing frequency (P < .001), [Formula: see text] (P = .01), and [Formula: see text] (P < .004). There were significant differences between groups for route of admission (P = .02), high-flow nasal cannula use (P < .001), and use of a helium-oxygen mixture (P < .001). There were significant differences between groups for median hospital LOS (1.2 vs 2.3 vs 3.4 d, P < .001), PICU LOS (0.39 vs 1.3 vs 2 d, P < .001), and time on continuous albuterol (7.4 vs 20.6 vs 34.7 h, P < .001). After adjusting for demographics and medical history, the incidence risk ratio for hospital LOS was 2.09 for PICU admission for an MPIS of 6-9 and 2.68 for an MPIS ≥ 10 when compared to an MPIS < 6.

Conclusions: The MPIS thresholds used in our pathway appropriately predicted LOS in our cohort of subjects with asthma admitted to the PICU. Higher MPIS was associated with increased hospital LOS, PICU LOS, and time on continuous albuterol.

Keywords: MPIS; asthma; asthma scoring; children; modified pulmonary index score; pediatric; pediatric intensive care unit; status asthmaticus.