Effects of mild cognitive impairment and sleep disorders on the minimum alveolar concentration value of sevoflurane

Objectives: To explore the effect of mild cognitive impairment (MCI) and MCI with sleep disorders on the potency of sevoflurane anesthesia in the elderly.

Design: Prospective study methods. Dixon up-and-down methods.

Setting: Comprehensive public tertiary hospital, Cangzhou City, Hebei Province, China.

Participants: 70 elderly patients scheduled for elective unilateral breast cancer surgery and finally analyzed 58 patients, including 30 patients with MCI (group M) and 28 patients with MCI with sleep disorders (group MS).

Outcome measures: The required minimum alveolar concentration (MAC) value of sevoflurane in the two groups was determined using the Dixon up-and-down method. The MAC value of sevoflurane and its 95% confidence interval (CI) were calculated using the logistic regression method. Serum melanin-concentrating hormone concentrations were determined by Elisa kits.

Results: The MAC value of sevoflurane in group M was 1.43 (95% CI 1.05-1.61%), and the MAC value of sevoflurane in group MS was 1.93 (95% CI 1.78-2.08%), There were notable differences between the two groups (P < 0.0001). The level of melanin-concentrating hormone (MCH) in the MS group was significantly lower than that in the M group (21.52 ± 3.82 vs. 37.17 ± 3.66 pg/ml, P < 0.0001). There was a significant negative correlation between MCH levels and the probability of body movement during skin incision (OR = 0.844, 95% CI: 0.715-0.996, P = 0.045).

Conclusions: Patients with MCI with sleep disorders required higher doses of sevoflurane than those with MCI alone. Changes in anesthetic requirements may be related to changes in MCH levels.