Hospital Asthma Severity Score: Validation in Pediatric Exacerbations

The intraclass correlation coefficient of the Hospital Asthma Severity Score (HASS) was found to be higher than that of the Pediatric Respiratory Assessment Measure (PRAM) when used for the evaluation of inpatient asthma exacerbation severity in patients 2 to 18 years of age, according to results of a study published in the Journal of Asthma. A prospective study (ClinicalTrials.gov Identifier: NCT02782065) was conducted to validate the HASS against the PRAM and spirometry at a single point in time.

The HASS was developed as a practical tool that utilizes reliable clinical guides, regardless of age or physique, to accurately establish inpatient asthma management via escalation or de-escalation of treatment. Each of the individual components of the HASS is rated from 1 to 3, which yields an overall score that ranges from 5 to 15. Face validity of the HASS was determined by consensus from a panel of more than 20 providers from emergency departments, intensive care units, and acute inpatient hospital units.

The current study was conducted in the inpatient, intermediate, and critical care units of a 404-bed urban, tertiary care, freestanding children’s hospital. Inter-rater agreement of HASS and PRAM scores was evaluated between 2 blinded clinician raters. All eligible participants, who were between 2 and 18 years of age, were identified by their primary diagnosis of asthma via use of the inpatient electronic medical record system. Exclusion criteria included being on continuous albuterol; requiring advanced airway protective treatments (ie, noninvasive ventilation or intubation); and/or having a diagnosis of bacterial or viral lung infection, chronic lung disease, cardiac disease, or kidney disease.

The investigators reported 116 total observations of HASS (raters 1 and 2) and 116 observations of PRAM (raters 1 and 2) among the 58 patients included in the study. Length of hospitalization for participants ranged between 0 and 6 days (mean, 1.69 days), with study evaluations completed on days 0 through 6 of hospitalization (mean, day 1.03). Overall, 41% (24 of 58) of the participants were younger than 7 years of age, and there was an approximately equal number of male patients and female patients included. The majority of the participants were either Black/African American (40%) or White (30%).

Patients were receiving treatment in critical care units (12.1%), intermediate care units (12.1%), and inpatient units (75.8%). All of the participants were receiving nebulizer treatments for the management of their asthma: 1.7% every hour, 20.7% every 2 hours, 32.8% every 3 hours, and 44.8% every 4 hours. Additionally, 3% (2 of 58) of the participants were receiving oxygen via nasal cannula.

When continuous total scores were used to review agreement between the 2 raters, HASS demonstrated 29% exact agreement compared with 28% exact agreement with PRAM. When a 1-point difference was permitted between the raters, a 79% rater agreement was reported for the HASS compared with a 60% rater agreement for the PRAM. Mean total scores for the HASS and PRAM were 6.26 vs 1.38, respectively. Moderate reliability for the HASS (0.68; 95% CI, 0.47-0.82) and PRAM (0.51; 95% CI, 0.17-0.71) total scores was reported based on Koo and Li classifications for intraclass correlation coefficients.

When the scores were categorized as mild, moderate, or severe, inter-rater agreement was 62% for the HASS vs 93% for the PRAM (P <.0001). In addition, intra-rater agreement between severity categories of HASS and PRAM was 71% for rater 1 and 64% for rater 2. A weak correlation was observed between both the HASS and forced expiratory volume in 1 second (FEV₁; P =.11), as well as between the PRAM and FEV₁ (P =.11) for the 29 participants who had acceptable spirometry results.

The investigators concluded that the results of the current study support the validation of HASS for the management of hospitalized pediatric patients during asthma exacerbations. Future validation efforts should be limited to comparison with validated tools that are used for the evaluation of the findings from patients’ physical examinations.

Reference

Abecassis L, Gaffin JM, Forbes PW, Schenkel SR, McBride S, DeGrazia M. Validation of the Hospital Asthma Severity Score (HASS) in children ages 2-18 years old. J Asthma. Published November 16, 2020. doi:10.1080/02770903.2020.1852414