Table 1.
Characteristics of included studies.
| Author | Sex (M/F) | Surgery | Anesthesia method | TEAS group | Control group | Outcomes | |||
|---|---|---|---|---|---|---|---|---|---|
| Method | Acupoint | NO. | Method | NO. | |||||
| Qian, 2021 | 23/41 | Open spinal surgery | i | A 2/100 Hz ab, <10 mA | LI4 PC6 | 32 | ① | 32 | POD at postoperative 7 days (CAM) and DNR at 1 month (TICS-m). |
| Chang, 2021 | 50/35 | Total hip arthroplasty | iv | B 2/100 Hzab, 6–10 mA | HT7 LI4 PC6 | 44 | ① | 41 | POD at 1 day, 3 days, and 5 days postoperatively (CAM) and DNR at 1 month and postoperative NCD at 3 months (neuropsychologic test battery). |
| Wu et al, 2021 | 35/25 | Gastrointestinal cancer Operation | ii | B 2/100 Hzab, 1–30 mA, 0.25 ms | HT7 ST36 PC6 | 30 | ① | 30 | POD at postoperative days 1–7 (CAM). |
| Zhang, 2021 | 27/59 | hip fracture | v | A 2/100 Hzab, 1–7 mA | GV24 GV29 LI4 PC6 | 43 | ① | 43 | POD during the first 3 days after surgery (CAM). |
| Gao et al 2018 | 33/31 | Spine surgery | i | A 2/100 Hzab | LI4 PC6 | 32 | ① | 32 | The incidence of POD during the first 3 days after surgery (CAM-ICU). |
| Liu, 2019 | 82/38 | Radical mastectomy | i | D 2/100 Hzab, 6–10 mA | LI4 PC6 | 59 | ① | 59 | POD at postoperative days 1–3 (CAM-ICU). |
| Wang et al, 2016a | 34/26 | General anesthesia laparoscopic Gastric cancer radical surgery and rectal colon cancer radical surgery | i | A 2/60 Hzab, 8–12 mA | GV20 PC6 ST36 SP6 | 30 | ② | 30 | DNR at 1 day, 3 days, and 7 days postoperatively (MMSE). |
| Wang et al, 2016b | 36/24 | Artificial femoral head replacement | vi | F 2/60 Hzab, 8–12 mA | GV20 PC6# ST36* SP6* | 30 | ② | 30 | DNR at 1 day, 3 days, and 7 days postoperatively (MMSE). |
| Wu and Luo, 2020 | / | Elective noncardiac surgery | i | E 2/60 Hzab, 6 mA | LI4 PC6 | 42 | ① | 42 | DNR at 1 day, 3 days, and 7 days postoperatively (MoCA and MMSE). |
| Tan et al, 2017 | 41/29 | Cholecystectomy | / | G 2/100 Hzab, 0.2–0.6 ms, GV20, PC6: 3～4 mA; ST36, SP6: 6～8 mA | GV20 PC6 ST36 SP6 | 35 | ① | 35 | DNR at 3 days, and 7 days postoperatively (MMSE). |
| Wei et al, 2021 | 39/63 | Hip replacement | iii | C 100 Hzbc | HT7 PC6 | 50 | ① | 52 | POD during the first 3 days after surgery (CAM). |
| Tang and Qing, 2017 | 49/41 | Colorectal cancer surgery | i | A 2/100 Hzab | GV20 GV24 | 45 | ② | 45 | DNR at 1 day, 3 days, 5 days, and 7 days after surgery (MMSE). |
| Wang et al, 2021 | 24/26 | laparoscopic radical bladder cancer surgery | ii | H 2 Hzcd | GV20 PC6 ST36 SP6 | 27 | ② | 29 | DNR at 1 week (MMSE). |
i: Intravenous general anesthesia; ii: Intravenous and inhalational combined anesthesia; iii: Nerve block anesthesia was administered in the supine position, and after pain relief, intraspinal or general anesthesia was administered. For intravertebral anesthesia, combined spinal-epidural anesthesia was administered, and the anesthesia was maintained by intravenous and inhalational combined anesthesia; iv: Subarachnoid block anesthesia in combination with fascial iliac block; v: Combined spinal-epidural anesthesia in combination with fascial iliac block; vi: Combined spinal-epidural anesthesia.
A: 30 minutes before anesthesia to the end of the surgical suture; B: 30 minutes before the start of anesthesia and at PM8:00 on the 1st, 2nd, and 3rd postoperative days, half an hour each time; C:30 min before surgery, 18:00 on the day of surgery, 18:00 on the first day after surgery, 18:00 on the second day after surgery, half an hour each time; D: After anesthesia until the end of the procedure; E: Lasting at the beginning of anesthesia until the end of surgery; F: TEAS group was continually treated before anesthesia to the end of the operation; G: Preoperative 1 day to 7 days postoperative in the morning, 30 minutes each time, 1 time a day; H: 10 minutes before induction of anesthesia until the end of the surgery.
a: 2 Hz (low-frequency) and the 100 Hz (high-frequency) exchange output; b: intensity of tolerable level; c: The current frequency is continuous wave; d: no mentioned of frequency.
LI4: Hegu; PC6: Neiguan; HT7: Shenmen; ST36: Zusanli; SP6: Sanyinjiao; GV20: Baihui; GV24: Shenting; GV29: Yintang. #: bilateral; *: healthy side. ①: Sham intervention; ②: No treatment.
CAM = confusion assessment method, CAM-ICU = confusion assessment method for the intensive care unit, DNR = delayed neurocognitive recovery, MMSE = mini-mental state examination, MoCA = montreal cognitive assessment, POD = postoperative delirium, postoperative NCD = postoperative neurocognitive disorder, TICS-m: telephone interview for cognitive status-modified.