Clinical studies of induction agents XLIII: Flunitrazepam

Area of Science:

• Anesthesiology
• Pharmacology

Background:

• Flunitrazepam (Ro 5-4200) is a benzodiazepine derivative.
• Its potency was estimated to be 10 times that of diazepam.

Purpose of the Study:

• To evaluate flunitrazepam as an induction agent for anesthesia.
• To assess its efficacy, safety, and recovery profile in volunteers and patients.

Main Methods:

• A study involving 220 volunteers or patients.
• Administration of flunitrazepam as an induction agent.
• Observation of onset of action, patient response, and recovery characteristics.

Main Results:

• Maximum soporific effect observed 90-120 seconds post-injection.
• Significant individual variation in response; some patients did not lose consciousness even with 6 mg.
• Opiate premedication enhanced effect but delayed recovery.
• Dose-related respiratory upset in unpremedicated patients.
• High frequency of arterial hypotension with large doses and opiate premedication.
• Venous sequelae comparable to diazepam.

Conclusions:

• Flunitrazepam demonstrated unsatisfactory efficacy for anesthesia induction.
• Prolonged recovery times render it unsuitable for routine use.
• Safety concerns include respiratory upset and hypotension, particularly with opiate premedication.