The Preventive Effect of Transcutaneous Electrical Acupoint Stimulation on Postoperative Delirium in Elderly Patients with Time Factors: A Randomized Trial

Objectives: There is currently no exact and effective treatment for postoperative delirium (POD). The purpose of this study was to observe the effect of transcutaneous electrical acupoint stimulation (TEAS) before surgery and during surgery in elderly patients with POD. Materials and Methods: A total of 90 patients were randomly divided into three groups: a preoperative TEAS group (group E1), an intraoperative TEAS group (group E2), and a control group (group C). In group E1, TEAS was applied at the Shenting, Baihui, bilateral Neiguan, and Hegu points for 30 min 1 day before surgery and before the induction of anesthesia. In group E2, TEAS was applied during surgery. In group C, electrodes were applied to the points just cited, but no electric stimulation was administered. The incidence of delirium was assessed within 5 days after surgery, and the plasma concentration of propofol at bispectral index (BIS) = 50 was recorded. Blood samples were collected to measure neuron-specific enolation (NSE), tumor necrosis factor-α (TNF-α), and interleukin (IL)-1β 1 day before surgery and 1 and 5 days after surgery. Results: The incidence of delirium in group E1 was decreased in comparison with group C and group E1 (both p < 0.05). The propofol plasma concentration at BIS = 50 in group E1 was also decreased in comparison with group C and group E2 (both p < 0.05). Compared with group C, the concentrations of NSE, TNF-α, and IL-1β in plasma were decreased in group E1 and group E2 1 and 5 days after surgery (both p < 0.05), and the concentrations of NSE and IL-1β in plasma in group E1 were decreased 1 and 5 days after surgery in comparison with group E2. Conclusion: The TEAS can reduce the dosage of propofol required during surgery and the occurrence of delirium after surgery. Its mechanism may be related to inhibiting inflammation response and alleviating brain injury. Compared with intraoperative application, the effect of preconditioning with TEAS before surgery is better. Clinical Trial Registration: ChiCTR-INR-17012501. Date of registration: August 29, 2017