Safety and efficacy of esketamine versus remifentanil as adjuncts to propofol sedation in children undergoing haematologic-oncologic procedures in China: a single-centre, randomised, controlled, crossover trial protocol.

introductionAdequate sedation is essential for paediatric patients undergoing invasive haematologic-oncologic procedures. The combination of propofol and remifentanil is commonly used yet is associated with respiratory depression. Esketamine has anaesthetic, analgesic and sympathomimetic properties and is known to cause less respiratory depression than other sedatives. This study aims to assess esketamine versus remifentanil in combination with propofol for invasive haematological-oncological procedures for paediatric patients. METHODS AND ANALYSIS: This prospective, randomised, double-blind, two-period crossover trial will include 80 paediatric patients aged 6-12 years, with American Society of Anesthesiologists Physical Status II to III, who are scheduled to undergo repeated invasive procedures including bone marrow aspirates and lumbar punctures under sedation. Participants will be randomised to two sequences: AB or BA. In sequence AB, children will receive propofol (3 mg/kg) and esketamine (0.5 mg/kg) in period 1 and propofol (3 mg/kg) and remifentanil (1 µg/kg) in period 2. In sequence BA, the order is reversed. The primary endpoint of this trial is the incidence of desaturation events, defined as SpO ETHICS AND DISSEMINATION: The trial was approved by the Ethics Committee of the Children's Hospital of Soochow University (Approval No. 2025008). The results of this trial will be submitted for peer review and publication in a scientific journal. TRIAL REGISTRATION NUMBER: ChiCTR2500098533.