Introduction: Rebound tachycardia has been observed in pediatric patients following Dexmedetomidine exposure. While it may occur even after short-term use, its incidence in the context of prolonged infusions and temporary interruptions remains unclear. Methods: Design: This is a single-center, retrospective observational study conducted in a pediatric intensive care unit. Definitions: •Prolonged Dexmedetomidine infusion was defined as continuous administration for ≥240 hours. •Rebound tachycardia was defined as an increase in heart rate of ≥20% compared to baseline, observed within 72 hours following discontinuation or within 5 days following temporary interruption. •Baseline heart rate was defined as the median value recorded during the 30-minute period immediately preceding either the discontinuation or temporary interruption of Dexmedetomidine. •Heart rate data, recorded at 1-minute intervals, were retrospectively extracted from the Pediatric ICU’s electronic medical record system. Results: Between April 2019 and March 2024, 4,327 patients were admitted to the PICU or equivalent ward. Among them, 122 received Dexmedetomidine for ≥240 hours. •After complete discontinuation, 22 patients (18.0%) experienced rebound tachycardia within 72 hours (Figure 1). Statistical analysis revealed no significant association between weaning duration and rebound occurrence (Wilcoxon p=0.57; logistic regression p=0.41). •Of 96 patients with temporary interruptions (237 episodes), 49 patients (95 episodes) were analyzed after excluding interruptions due to surgery, diagnostics, or pacemaker placement (Figure 2). •Median interruption duration was 517 minutes (range: 23-6,580). •Rebound tachycardia occurred in 25 episodes (32.7%) among 16 patients, observed up to 5 days post-interruption. Episodes tended to cluster around 24 and 72 hours post-interruption, though no statistically significant temporal pattern was confirmed. Conclusions: In pediatric patients receiving prolonged Dexmedetomidine infusions, rebound tachycardia occurred in 18.0% of cases after discontinuation and 32.7% after interruption. These findings highlight the importance of monitoring cardiovascular responses during and after changes in sedation protocols.
Isaka et al. (Sun,) studied this question.