Dose of Remimazolam in Children for Intubation

Inclusion Criteria: * age from 3 to 12 years old * patients scheduled for surgery under general anesthesia * Body mass index in the range of 5% -95% of the same age group * Consent was obtained from the patient and the family members, and an informed consent form was signed Exclusion Criteria: * American Society of Anesthesiologists status ≥3 * patients who cannot cooperate with intravenous anesthesia induction * patients with risk of difficult airway * patients who are allergic to benzodiazepines * patients with neurological dysfunction * Participate involved in other clinical investigators within 3 months