ObjectiveDexmedetomidine is an increasingly popular analgosedative in critically ill children receiving invasive mechanical ventilation (IMV). We conducted a systematic review to evaluate the efficacy of dexmedetomidine compared to other analgosedatives in this population.Data sourcesSeven electronic databases and trial registries to July 2024, without language restrictions.Study selectionRandomized controlled trials comparing dexmedetomidine to other analgosedatives in critically ill children receiving IMV.Data extraction and synthesisIndependently and in duplicate, we conducted data extraction, risk of bias assessment, and certainty assessment using Grading of Recommendations, Assessment, Development, and Evaluation. We conducted random-effects meta-analyses, calculating pooled risk ratios (RRs) and mean differences (MDs) with 95% confidence intervals.ResultsWe identified 12 trials (n = 592 patients). Pooled analyses demonstrated dexmedetomidine has little to no effect on IMV duration (MD -2.2 h [-3.3, -1.1]; moderate certainty), clinically important bradycardia (RR 1.42 [0.45, 4.49]; moderate certainty), or clinically important hypotension (RR 1.35 [0.48, 3.82]; moderate certainty). Dexmedetomidine may reduce delirium risk (RR 0.83 [0.64, 1.07]; low certainty), but impact on withdrawal is uncertain (RR 0.93 [0.55, 1.59]; very low certainty). A narrative synthesis was used to evaluate dexmedetomidine sedation efficacy, demonstrating very low certainty in attaining sedation target. One trial reported on long-term outcomes.ConclusionsTwelve trials evaluating dexmedetomidine have been conducted to date, with low or very low certainty for its impact upon delirium, withdrawal, and long-term outcomes. Future analgosedation trials require attention to intervention design, outcome selection and reporting to improve certainty in critical outcomes.