Immediate retrograde amnesia induced by midazolam: a prospective, nonrandomized cohort study

Area of Science:

• Anesthesiology
• Pharmacology
• Neuroscience

Background:

• Midazolam is a short-acting benzodiazepine used for procedural sedation due to its rapid onset, short duration, and low toxicity.
• While known for anterograde amnesia, the potential for midazolam to induce retrograde amnesia requires further investigation.
• Cesarean delivery presents a unique context to study midazolam's effects on memory.

Purpose of the Study:

• To evaluate the presence and extent of retrograde amnesia induced by midazolam in patients undergoing cesarean delivery.
• To assess the impact of midazolam on visual and event memory recall.
• To determine if midazolam affects episodic memory during the perioperative period.

Main Methods:

• A prospective cohort, nonrandomized study involving 100 parturients undergoing elective cesarean delivery under spinal anesthesia.
• Patients were shown six picture cards at one-minute intervals post-delivery.
• Midazolam (0.1 mg/kg) was administered based on patient preference, with retrograde recall rates assessed by a blinded investigator.

Main Results:

• The midazolam group exhibited a significantly lower overall retrograde card recall rate (77.0%) compared to the control group (87.7%).
• Recall was particularly diminished at one minute prior to midazolam administration (58% vs. 88% in controls).
• Patients receiving midazolam reported more spurious intraoperative events (26% vs. 4% in controls).

Conclusions:

• Intravenous midazolam can induce short-term retrograde amnesia affecting both visual and event memory.
• Midazolam administration may increase false reports of intraoperative events, suggesting an impact on episodic memory.
• The findings underscore the importance of considering midazolam's amnesic effects in obstetric anesthesia.