Effective doses of midazolam oral solution for the prevention of preoperative anxiety in paediatric patients.

BACKGROUND: More than 60% children exhibit anxiety before undergoing an anesthetic-surgical procedure, particularly among pre-school paediatric patients. Oral midazolam can provide procedural sedation for children prior to anesthesia. However, extemporaneous solutions of midazolam are usually prepared from injectable drug solutions, leading to inconsistent efficacy due to variable preparation methods. Xiaoerjing® is the first commercially available oral formulation of midazolam for procedural sedation in children in China. Despite the recommended dosage range of 0.25-0.5 mg/kg, its effective dose is still largely unknown.

AIM: To determine the 95% effective dose (ED95) of midazolam oral solution (Xiaoerjing®) for alleviating preoperative anxiety in children prior to mask induction of general anesthesia.

DESIGN: The study included 61 children between the ages of 1 and 6 years undergoing elective surgery under general anesthesia. The first patient received a single dose of 0.5 mg/kg midazolam oral solution, which was adjusted for subsequent patients using the biased coin design method based on their response to the previous dose. Doses were increased or decreased at the rate of 0.1 mg/kg. An effective response was defined as having a modified Ramsay sedation score ≥3a, separation anxiety score ≤2, and mask acceptance score ≤2 during inhalational anesthesia induction.

RESULTS: Fifty-six children were included in the final analysis. Of those, sedation was successful in 50 patients, with a median separation time of 15 (IQR: 25) min. Midazolam oral solution has an ED95 of 0.8254 mg/kg (95% CI: 0.6915-0.8700 mg/kg) for relieving preoperative anxiety in children. No adverse events occurred following drug administration.

CONCLUSION: Midazolam oral solution is a safe and effective medication for relieving preoperative anxiety in children. The ED95 of a single oral dose of midazolam oral solution is 0.8254 mg/kg (95% CI: 0.6915-0.8700 mg/kg).