Prevention of Cognitive Dysfunction after Cataract Surgery with Intravenous Administration of Midazolam and Dexmedetomidine in Elderly Patients Undergoing Cataract Surgery.

Background: This study aimed to compare the effects of preoperative administration of midazolam and dexmedetomidine on cognitive dysfunction prevention after cataract surgery.

Materials and Methods: This research was a double-blind controlled clinical trial. In this study, 150 candidates for cataract surgery under general anesthesia, over 65 years, and similar to American Society of Anesthesiologists I and II characteristics were selected as the sample and randomly assigned to three groups. Participants of these three groups were treated with 0.1 mg/kg of midazolam, 1 μg/kg of dexmedetomidine, and the same volume of normal saline (control), respectively. Hemodynamic parameters and cognitive dysfunction score of the participants were measured using the Mini-Mental State Examination (MMSE) before the surgery, 24 h and 1 week after the surgery.

Results: An evaluation of hemodynamic parameters before anesthesia up to 24 h after the surgery showed no significant difference between the midazolam, dexmedetomidine, and control groups in terms of systolic and diastolic blood pressure, heart rate, and blood oxygen saturation ( P > 0.05). In addition, there was no statistically significant difference between the midazolam and dexmedetomidine groups in the MMSE score before the surgery and 24 h and 1 week after that ( P > 0.05). However, there was a significant difference between these two groups and control ( P < 0.05).

Conclusion: There was no significant difference between midazolam and dexmedetomidine in reducing postoperative cognitive dysfunction (POCD). However, there is a significant difference between these two groups and control. Hence, either midazolam or dexmedetomidine can be prescribed to reduce POCD in cataract surgeries.