Dexmedetomidine and ketamine for sedation during spinal anesthesia in children.

STUDY OBJECTIVE: To evaluate the combination of dexmedetomidine and ketamine for sedation during lumbar puncture and sedation for spinal anesthesia in children.

DESIGN: Retrospective analysis of quality assurance data sheets and anesthetic records.

SETTING: Developing countries with the humanitarian group, Kids First.

PATIENTS: 12 infants and children, ranging in age from two to 9 years.

INTERVENTIONS: A bolus dose of ketamine (two mg/kg) and dexmedetomidine (one μg/kg) was given over three minutes followed by a continuous infusion of dexmedetomidine (two μg/kg/hr for the first 30 min, followed by one μg/kg/hr for the duration of the case). Supplemental analgesia/sedation was provided by ketamine (0.5 mg/kg) as needed.

MEASUREMENTS: The need for supplemental ketamine, the ability to complete the procedure, and heart rate (HR), blood pressure, end-tidal carbon dioxide (ETCO(2)), and oxygen saturation values were recorded.

MAIN RESULTS: Effective sedation for lumbar puncture and performance of spinal anesthesia were achieved in all patients. One patient required a supplemental dose of ketamine (0.5 mg/kg). Following the bolus dose of ketamine and dexmedetomidine, HR increased by 11 ± 4 bpm. The greatest HR increase was 20 bpm. No patient had a HR increase ≥ 20% from baseline. The HR decrease was ≤ 30 bpm in 10 of the 12 patients, and the greatest HR decrease was 58 bpm. Systolic blood pressure (SBP) increased from baseline by 10 ± 3 mmHg after administration of the bolus dose of ketamine and dexmedetomidine. During the subsequent dexmedetomidine infusion, SBP decreased by 11 ± 9 mmHg. No patient's respiratory rate decreased to less than 10 breaths/min or increased above 24 breaths/min during the procedural sedation. The highest ETCO(2) was 45 ± 2 mmHg (P < 0.0001). Oxygen saturation remained ≥ 95% during the procedure in all patients.

CONCLUSION: A combination of ketamine and dexmedetomidine provides effective sedation during spinal anesthesia in infants and children, with limited effects on cardiovascular and ventilatory function.