Pulse Oximetry, Vital Signs May Predict Hospital LOS in Pediatric Asthma Exacerbations

Heart rate, respiratory rate, and oxygen saturation (SpO₂) levels with percentile-based cutoffs can predict the risk of prolonged hospitalization in children admitted for an asthma exacerbation, according to study results presented at the American College of Allergy, Asthma, & Immunology (ACAAI) Annual Scientific Meeting, held virtually from November 13 to 15.

Although new reference values using centiles for heart rate and respiratory rate have been proposed, these values have not been evaluated in predicting hospital length of stay (LOS) in pediatric asthma exacerbations. Therefore, a team of US investigators conducted a retrospective analysis to identify the best model for predicting prolonged hospitalization rates, or hospital LOS for more than2 days in children admitted for an asthma exacerbation. The study included 695 pediatric admissions to a New York hospital as a result of an asthma exacerbation. Patient data collected and analyzed in this study included heart rate, respiratory rate, and SpO₂ information taken at the first encounter.

A 95% cutoff value was applied to SpO₂. Percentile-based cutoffs for heart rate and respiratory rate were assessed using the 99th as cutoff. Cutoffs higher than 99th were also explored. The best model that predicted prolonged hospitalization rates (longer than 2 days) were presented. Investigators also examined length of hospitalization, placing patients into LOS categories of fewer than 2 or 2 or more days.

In a model using Pediatric Advanced Life Support (PALS) cutoff values and SpO₂ less than 95%, the adjusted odds ratios (aORs) were 2.339 (95% CI, 1.59-3.487) for SpO₂ less than 95%, 1.089 (95% CI, 0.755-1.572) for PALS heart rate, and 1.125 (95% CI, 0.742-1.707) for PALS respiratory rate.

The best model predictive of prolonged hospitalization used cutoffs of higher than 99th and corresponded with aORs of 1.955 (95% CI, 1.307-2.926) for SpO₂ <95%, 1.578 (95% CI, 1.127-2.210) for heart rate of more than 10 above 99th, and 1.454 (95% CI, 1.038-2.035) for respiratory rate of more than 5 above 99th.

Reference

Camayo JR, Anbalagan S, Borjas P, et al. Pulse oximetry and centile-based vital signs predict hospital length of stay in pediatric asthma exacerbation. Presented at: the American College of Allergy, Asthma & Immunology (ACAAI) Annual Scientific Meeting (Virtual Experience). November 13-15, 2020. Abstract 027.