The correlation between orexin-A and early postoperative cognitive function in elderly patients undergoing lumbar surgery under general anesthesia / 解放军医学杂志

ABSTRACT

Objective To analyze the correlation between serum orexin-A (OXA) and early postoperative cognitive function in elderly patients undergoing lumbar spinal surgery under general anesthesia. Methods A total of 76 elderly patients (age ≥65 years) underwent lumbar spine surgery under general anesthesia from December 2018 to December 2019 in the Affiliated Hospital of Inner Mongolia Medical University were collected. All the enrolled patients were evaluated by the same doctor with the Montreal cognitive assessment scale (MoCA) on one day before the surgery and one to three days after the surgery, and venous blood was extracted from the patient on the operation day and one day after the operation, and the serum levels of OXA and S100β were measured by ELISA. According to the results of cognitive function assessment, the patients were divided into postoperative cognitive dysfunction (POCD) group and non-postoperative cognitive dysfunction (NPOCD) group. The differences in serum OXA and S100β protein levels between the two groups and their correlation with MoCA scores were statistically analyzed. Results There was no statistically significant difference in the MoCA score, serum OXA level, and S100β protein level before surgery, and heart rate (HR), mean artery pressure (MAP), bispectral index (BIS) and pulse oxygen saturation (SpO2) levels before anesthesia induction (T0), at the start of surgery (T1), at 1h after the start of surgery (T2), at the withdrawal time (T3), and at 15 minutes after extubation (T4) between the two groups (P>0.05). At the first, second, and third day after operation, the MoCA scores of the POCD group were lower than those before the operation, and they were both lower than those of the NPOCD group, the difference was statistically significant (P<0.001). There was a statistically significant difference in serum OXA levels between the two groups after the operation (P<0.05). The postoperative S100β protein level was higher than that before the operation in the two groups, and the POCD group increased more significantly, the difference between the two groups after the operation was statistically significant (P<0.05). The postoperative OXA level was positively correlated with the MoCA score (r=0.545, 0.531, 0.779) and negatively correlated with the S100β protein level (r=-0.591, -0.362, -0.743) in the two groups, and the difference was statistically significant (P<0.05). Conclusions The level of serum OXA is positively correlated with early postoperative cognitive function in elderly patients undergoing lumbal spine surgery under general anesthesia, suggesting that OXA may be a potential target for reducing the risk of postoperative cognitive dysfunction in such patients, so as to provide new ideas for preventing and improving the postoperative cognitive dysfunction in elderly patients in the future.