Midazolam: Mechanism and perioperative applications

Abstract Midazolam is the most commonly administered benzodiazepine in the perioperative setting. Midazolam is effective at achieving procedural sedation, hypnosis, anxiolysis, and anterograde amnesia. The mechanism of action for midazolam is mediated via its interaction with the GABAA receptor. Binding of midazolam to GABAA potentiates the effect of GABA induced chloride conductance, resulting in hyperpolarization of the postsynaptic membrane. This inhibitory postsynaptic potential decreases the probability of neurotransmission and is responsible for the clinical effects of midazolam. The rapid onset and relative short duration of action makes midazolam the benzodiazepine a safe choice for perioperative sedation. Midazolam’s multiple routes of administration makes it versatile even when IV access is unavailable. Flumazenil, which antagonizes benzodiazepines, further ensures the safety profile of midazolam in the setting of an overdose.