Effectiveness of Bradycardia as a Single Parameter in the Pediatric Acute Response System

Abstract

Background: Various tools for the acute response system (ARS) predict and prevent acute deterioration in pediatric patients. However, detailed criteria have not been clarified. Thus we evaluated the effectiveness of bradycardia as a single parameter in pediatric ARS. Methods: This retrospective study included patients who had visited a tertiary care children’s hospital from January 2012 to June 2013, in whom ARS was activated because of bradycardia. Patient’s medical records were reviewed for clinical characteristics, cardiologic evaluations, and reversible causes that affect heart rate. Results: Of 271 cases, 261 (96%) had ARS activation by bradycardia alone with favorable outcomes. Evaluations and interventions were performed in 165 (64.5%) and 13 cases (6.6%) respectively. All patients in whom ARS was activated owing to bradycardia and another criteria underwent evaluation, unlike those with bradycardia alone (100.0% vs. 63.2%, p = 0.016). Electrocardiograms were evaluated in 233 (86%) cases: arrhythmias were due to borderline QT prolongation and atrioventricular block (1 and 2-degree) in 25 cases (9.2%). Bradycardia-related causes were reversible in 202 patients (74.5%). Specific causes were different in departments at admission. Patients admitted to the hemato-oncology department required ARS activation during the night (69.3%, p = 0.03), those to the endocrinology department required ARS activation because of medication (72.4%, p < 0.001), and those to the gastroenterology department had low body mass indexes (32%, p = 0.01). Conclusions: Using bradycardia alone in pediatric ARS is not useful, because of its low specificity and poor predictive ability for deterioration. However, bradycardia can be applied to ARS concurrently with other parameters.