Effect of perioperative probiotic therapy on postoperative cognitive dysfunction after non-cardiac surgery under general anesthesia in elderly patients with frailty

Background Postoperative cognitive dysfunction (POCD) is a common complication in elderly patients, especially those with preoperative frailty. The incidence of preventive and/or therapeutic strategies remains limited. Objective To evaluate the effect of perioperative probiotic therapy on postoperative cognitive dysfunction in frail elderly patients undergoing non-cardiac surgery under general anesthesia. Methods After obtaining ethical approval and written informed consent, this randomised double-blind and placebo-controlled trial included 100 elderly frail patients scheduled for elective general anesthesia non-cardiac surgery were recruited from our hospital. Patients were assigned to receive either probiotics or placebo from admission to discharge. Participants (n = 100) were treated with probiotics or placebo from 2 day before surgery to 5 days after surgery, and participants were assessed by Mini-Mental State Examination (MMSE) before taking the drug and at 1, 7 and 14 days after surgery. The primary endpoint was the incidence of postoperative cognitive dysfunction, defined as a 3-point decrease in MMSE score from baseline to postoperatively. Secondary endpoints included postoperative sleep quality, gastrointestinal function recovery, and length of postoperative hospital stay. Results Compared with the control group, there was no significant difference in MMSE score before taking the drugs in the experimental group, and the MMSE score was higher on the first and seventh days after surgery, the incidence of postoperative cognitive dysfunction was reduced (On the first postoperative day, 11 of 50 patients [22%] vs. 21 of 50 patients [42%] P = 0.03, and on the seventh postoperative day, 4 of 50 patients [8%] vs. 12 of 50 patients [24%]P = 0.03), the postoperative exhaust time was shortened, and the sleep was improved (P < 0.05). Conclusion Perioperative probiotic therapy can reduce the incidence of postoperative cognitive dysfunction and improve the postoperative sleep state of frail elderly patients undergoing general anesthesia non-cardiac surgery.