Efficacy and Safety of Transcutaneous Electrical Acupoint Stimulation (TEAS) for Postoperative Pain in Laparoscopy: A Systematic Review and Meta-Analysis of Randomized Controlled Trials

Table 2

Characteristics of the included studies.

No.	Study ID	Types of surgery	Intervention time	Sample size(T/C)	Intervention measures		Outcomes	Acupoints	Waveforms	Electrical frequency
					Intervention Group	Control Group
1	Mi et al. 2018 [21]	Hepatobiliary surgery	Before induction of anesthesia—the end of surgery	50/50	TEAS	Sham-TEAS	②③	LI14,PC6,ST36	Dilatational waveform	2/100 Hz
2	Yao et al. 2015 [22]	Gynecologic surgery	Before induction of anesthesia—the beginning of surgery	35/36	TEAS	Sham-TEAS	①②③	LI14,PC6,ST36,SP6	Dilatational waveform	2/10 Hz
3	Liu et al. 2008 [23]	Hepatobiliary surgery	Before induction of anesthesia—the end of surgery	48/48	TEAS	Sham-TEAS	④	PC6	Dilatational waveform	2/100 Hz
4	He 2017 [24]	Gynecologic surgery	S-TEAS: before anesthesia induction—the beginning of anesthesia; L-TEAS: before induction of anesthesia—the end of surgery	34, 33/34	TEAS	Sham-TEAS	①	LI14, ST36	Dilatational waveform	2/10 Hz
5	Cai et al. 2020 [25]	Gastrointestinal surgery	Before induction of anesthesia—the beginning of surgery	24/25	TEAS	Sham-TEAS	①	ST36,PC6	Dilatational waveform	2/15 Hz
6	Guo et al. 2016 [26]	Gynecologic surgery	Before induction of anesthesia—the end of surgery	30/30	TEAS	Sham-TEAS	⑤	PC6,ST36	Dilatational waveform	2/100 Hz
7	Zhou 2019 [27]	General surgery& Gynecologic surgery	Before induction of anesthesia—the end of surgery	32/32	TEAS	Sham-TEAS	①	SP6,LI14	Dilatational waveform	2/100 Hz
8	Duan 2017 [28]	Gynecologic surgery	Before induction of anesthesia—the end of surgery	64, 65, 63/64	Group-D:TEAS (double acupoints); Group-P, S (single acupoint)	Sham-TEAS	①③	groupD:PC6,ST36, group-P:PC6, group-S:ST36	Dilatational waveform	2/10 Hz
9	Gu 2019 [29]	Gastrointestinal surgery	S-TEAS, L-TEAS: the beginning of the operation—the end of the operation	49, 49/48	S-TEAS+PCIA；L-TEAS+PCIA	Sham-TEAS	①②	ST36,PC6	Dilatational waveform	2/100 Hz
10	Huang and Liu 2019 [30]	Gastrointestinal surgery	30 min before induction of anesthesia and lasting for 40 min	46/46	TEAS	Sham-TEAS	②	GV20,PC6,ST36,SP6	not reported	not reported
11	Song 2020 [31]	Gastrointestinal surgery	Before induction of anesthesia—the end of surgery	25/25	TEAS	Sham-TEAS	①	LI14,PC6	Dilatational waveform	5/100 Hz
12	Sun et al. 2016 [32]	Hepatobiliary surgery& Gynecologic surgery	Each perioperative treatment lasted 30 min	91, 91, 89/90	Group-A, B, C (different intervention time)	Sham-TEAS	①②	LI14,PC6	Dilatational waveform	2/100 Hz
13	Yin et al. 2013 [33]	Gynecologic surgery	Before induction of anesthesia—the end of surgery	30/30	TEAS	Blank control	①	ST36,ST34	Continuous waveform	2Hz
14	Yu et al. 2020 [34]	Gynecologic surgery	Before induction of anesthesia—the beginning of surgery	30/30	TEAS	Blank control	①②③	GV20,GV29,ST36,PC6	Dilatational waveform	2/100 Hz
15	Wang and Zhang 2015 [35]	Gynecologic surgery	Before induction of anesthesia—the end of surgery	58/58	TEAS	Blank control	①	ST34,ST36	Continuous waveform	2Hz
16	Xun et al. 2014 [36]	Hepatobiliary surgery	Before induction of anesthesia—the end of surgery	25/25	TEAS	Blank control	⑤	PC6,ST36	Dilatational waveform	2/100 Hz
17	Huang 2015 [37]	Gynecologic surgery	Before induction of anesthesia—the end of surgery	50/50	TEAS	Blank control	①	ST36,ST34	Continuous waveform	2Hz
18	Chen et al. 2017 [38]	General surgery	Before anesthesia induction—the beginning of anesthesia	20, 20/20	Group A: TEAS; group B: TEAS (different acupoints)	Blank control	①②	group-A:PC6,ST36; group- B:PC6,ST36,BL32,BL34	Dilatational waveform	2/100 Hz
19	Guo et al. 2017 [39]	Hepatobiliary surgery	Before anesthesia induction—after surgery	40/40	TEAS + PCIA	PCIA	①	EX-HN1,HT7,PC6	not reported	2/100 Hz
20	Deng et al. 2013 [40]	Gynecologic surgery	Before induction of anesthesia—the end of surgery	100/100	TEAS + PCEA	PCEA	①	PC6,ST36	not reported	2/100 Hz
21	Zheng et al. 2017 [41]	Gynecologic surgery	after the surgery	30/30	TEAS + PCIA	PCIA	①②⑤	LI14,PC6,ST36,SP6	Dilatational waveform	2/100 Hz
22	Gu et al. 2018 [42]	Gastrointestinal surgery	S-TEAS: the induction of anesthesia—the end of surgery; L-TEAS:before anesthesia induction—after surgery	60, 60/60	S-TEAS+PCIA;L-TEAS+PCIA	Sham-TEAS + PCIA	①②	ST36,PC6	Dilatational waveform	2/100 Hz
23	Zhao 2014 [43]	Gynecologic surgery	Before induction of anesthesia—the beginning of surgery	35/36	TEAS + PCIA	Sham-TEAS + PCIA	①②③	LI14,PC6,ST36,SP6	Dilatational waveform	2/10 Hz
24	Wei et al. 2017 [44]	Gynecologic surgery	Before induction of anesthesia—the end of surgery	30/30	TEAS + analgesics	analgesics	①	ST36,ST34	Dilatational waveform	2/100 Hz
25	Liu et al. 2020 [45]	Gastrointestinal surgery	Before anesthesia induction—after surgery	30/30	TEAS + standard analgesic regimen	standard analgesic regimen	①	LI14,PC8,ST36	Dilatational waveform	2/100 Hz
26	Bing et al. 2016 [46]	Gynecologic surgery	after the surgery	30/30	TEAS + postoperative routine nursing	postoperative routine nursing	①	GB21,BL12,GV6, GV4, etc.	Dilatational waveform	0.02 Hz
27	Huang et al. 2019 [47]	Gastrointestinal surgery	Before induction of anesthesia—the end of surgery	29/28	TEAS + TAP + PCIA	TAP + PCIA	①	ST36	Dilatational waveform	2/10 Hz
28	Huang 2018 [48]	Gastrointestinal surgery	Before induction of anesthesia—the end of surgery	32/35	TEAS + TAP + PCIA	TAP + PCIA	①	ST36	Dilatational waveform	2/10 Hz

Explanation: Outcomes: ① VAS values at different time points after operation; ② consumption of analgesics; ③ QoR-40 scare score; ④ VRS values at different time points after operation; ⑤ incidence of postoperative pain; acupoints: Zusanli ST36, Neiguan PC6, Hegu LI14, Sanyinjiao SP6, Baihui GV20, Liangqiu ST34, Yintang GV29, Ciliao BL32, Xialiao BL34, Shenmen HT7, Laogong PC8, Guanyuan GV4, Qihai GV6, Jianjing GB21, Fengmen BL12, Sishencong EX-HN1.