Volume 5, Number 1 | Spring 2010

Japanese Acupuncture - Current Research
Effects of Electroacupuncture Analgesia on Postoperative
Pain after Abdominal Surgery and the Presence of Endogenous
Analgesic Substances
Keisou Ishimaru
Faculty of Health Sciences, Ryotokuji University

IntroductionWe
investigatedtheeffectsofelectroacupuncture through a systematic review
of randomized controlled trials (RCTs) inpostoperative pain. 1)
The results are based on fifteen RCTs
comparing electroacupuncture with sham control
in the management of acute postoperative pain.
The results included one Japanese study(RCTs) by Ishimaru et al (1999). 2-3)
We
have
previously
reported
thatelectroacupuncture decreased the postoperative
pain after abdominal surgery and significantly
reduced the use of analgesic drugs, however, themechanism of electroacupuncture analgesia has
not been completely explained. In this study, The
effects of surgical invasion and electroacupuncture
analgesia
onserumbeta-endorphin,anendogenous opioid peptide that is involved inanalgesic action, and adrenocorticotropic hormone(ACTH) levels were evaluated.
Methods
Continuous frequency 3Hz electroacupuncture
treatment was performed at acupuncture point
LI4 (Hegu) and S36 (Zusanli) for 3 hours from 3hours after the operation in 11 patients(electroacupuncture group). Another elevenpatients not treated by non-electroacupuncture
served as controls. Peripheral blood (5 ml) wascollected before, during, immediately after
operation and at 3 hour intervals thereafter until
12 hours after the operation, and serumbeta-endorphin and ACTH levels were measured
by radioimmunoassay (RIA).
Results
Surgical procedure and anesthesia time andchanges in serum beta-endorphin and ACTH from2

before operation until 12 hours after operation intheelectroacupuncturegroup
andnon-electroacupuncture control group.
During the operations, both beta-endorphin
and ACTH levels increased significantly. Afterthe operations, these levels tended to gradually
decrease to preoperative values, but the levels of
serum beta-endorphin increased significantly
again during the electroacupuncture treatment in
the electroacupuncture group (Table 1.2.).
The degree of the postoperative pain in theelectroacupuncture and non-electroacupuncturegroup and the consumption of the analgesic drugs(Table 3.4.).
Analgesic drugs for postoperative pain wereused in 10 of the 11 cases in the control
non-electroacupuncture group (Table 4.), but wereused only in 1 of the 11 cases in theelectroacupuncture group (Table 3).
These results suggest that the beta-endorphin
levels induced by electroacupuncture reduced the
postoperative pain. The results also suggest that,even under general anesthesia, the surgicalinvasions appear to induce the central nervous toactivate stress-induced analgesia.
Discussion
Intheseresults,
wefoundthatelectroacupuncture is effective for postoperative
pain management, as demonstrated by asignificant reduction of postoperative pain scores
andendogenousopioids
includingbeta-endorphins. From other studies, likewise
electroacupuncture may reduce analgesic drugs
usage in the early postoperative period. 4-9)
Somestudies
suggestedthatelectroacupuncture
mechanisms
includeactivation of the endogenous pain inhibitory
system, release of endogenous opioids including
beta-endorphins, enkephalins, and dynorphins,and non-opioid substances such as serotonin,
norepinephrine, adenosine A1 receptor.10)
Future studies (RCTs) should investigate
electroacupuncture mechanisms given before orafter surgery.

The Journal of Kampo, Acupuncture and Integrative Medicine (KAIM)

Volume 5, Number 1 | Spring 2010

Serum beta-endorphin pg/ml
Serum ACTH pg/ml
patients
No.

agesexsurgical procedure

duration of anesthesia(minutes)

167

F

choledochojejunostomy

220

271

M

colectomy

170

371

M

total gastrectomy

395

457

F

cholecystectomy

160

567

M

cholecystectomy

75

641

M

subtotal gastrectomy

175

757

M

subtotal gastrectomy

210

865

F

high anterior resection

166

888

M

miles operation anddescending colostomy

225

1082

F

subtotal gastrectomy

200

1153

F

subtotal gastrectomy

166

65.3±13.2 years

196.4±77.5

before ope

during ope

after ope

3 hoursEA

6 hours

9 hours

12 hours

355
3
19
549
260
415
7
28
3
8
545
290
682
4
20

41
370
38
90
47
170
22
260
30
180
44
350
37
420
66
790
62
580
44
160
64
320

47
150
53
90
25
140
26
370
1289
32
380
460
24270
46
540
45
130
46
540

1090
771
898
899
1189
11
40
20
210
919
22
190
40
92
2290

870
652
480
2260
1560
28
30
16
1015
933
60
45
95
33
60

105033047126706131827316168464023804040105031357084961372838410146010301460

4.0±1.642.8±27.4

45.0±14.0
335.4±205.7

32.7±15.9
250.8±180.0

15.2±10.0
98.9±56.1

20.4±13.0
53.2±27.0

17.7±14.840.4±24.8

7.6±3.932.0±21.7

Table 1. Surgical procedure and anesthesia time and changes in serum beta-endorphin and ACTH from before operation until 12hours after operation in the electroacupuncture group. Normal value : Serum beta-endorphin 1-10 pg/ml, Serum ACTH 5.5-50 pg/ml.
EA : Electroacupuncture stimulation.
Serum beta-endorphin
Serum ACTH
patients
No.

duration ofage

sex

surgical procedure

anesthesia

before ope

during ope

after ope

3 hours

6 hours

9 hours

12 hours
3(minutes)

163

M

subtotal gastrectomy

150

268

M

high anterior resection

225

370

M

sigmoidectomy

150

481

M

cholecystectomy

120

574

M

subtotal gastrectomy

215

671

M

low anterior resction

210

7pg/ml

pg/ml

74

M

total gastrectomy

225

831

M

subtotal gastrectomy

180

880

F

cholecystectomy

501069M1170

F

68.2±13.4 years

subtotal gastrectomy andcholecystectomy
total gastrectomy

290
205

183.6±64.0

325433352

350

140

60

50

40-

335

9833

337

190

90

90

63

55

38

7698

75727

180

98

82

80

59

52

514

13

3

13

5616

83

64

5

6

5

56

1620

888935

110

160

1914

12

174

33

23

28

23

19

20

33

160

82

120

30

1830

544

48

16

15--

24210

320

54

66--

534

33

6765

19640

450

1824

28

19

34833333145

75

1810163153630231076604601306030605392922211814108018014993808060

5.0±1.825.0±13.2

19.9±13.2

11.5±8.9

10.0±6.6

7.3±5.2

7.2±5.1

37.6±19.2

237.1±178.0

159.8±119.3

56.2±37.6

41.1±27.7

37.3±25.2

33.8±18.5

Table 2. Surgical procedure and anesthesia time and changes in serum beta-endorphin and ACTH from before operation until 12hours after operation in the non-electroacupuncture group. Normal value : Serum beta-endorphin 1-10 pg/ml, Serum ACTH 5.5-50

The Journal of Kampo, Acupuncture and Integrative Medicine (KAIM)

3Volume 5, Number 1 | Spring 2010

Postoperativepain and the relations of the use pain-killer

patients
No.

after ope

3 hoursEA

6 hours

9 hours

12 hours

122

100

222110322000

4

22000

51

1

100

622

110

10

722

3
Voltaren50mg

8

1

1

100

922

100

102

2000

11221

10

Table 3. The degree of the postoperative pain in the electroacupuncture group and the consumption of theanalgesic drugs.
EA: Electroacupuncture stimulation.
The evaluation of the pain. 0:no pain, 1: movement pain, 2:rest pain, 3: use of the analgesic drugs.

Postoperative

pain and the relations of the use pain-killer

patientsNo.

after ope

3 hours

6 hours

9 hours

12 hours

12

2

3
pentazocin 1A

10

2

1

1

1

1

1

32

2

10

4

2

2

10

5

2

2

2

62

12

7

1

3
pentazocin 1A

82

2

92

2

10

1

2

112

2

3
voltaren 25mg
3voltaren 25mg
3voltaren 25mg
3
voltaren 25mg
3voltaren 50mg

3voltaren 50mg
3
pentazocin 1A

3voltaren 25mg
3voltaren 25mg

11220000102

2

Table 4. The degree of the postoperative pain in the non-electroacupuncture group and the consumption ofthe analgesic drugs.
The evaluation of the pain. 0:no pain, 1: movement pain, 2:rest pain, 3: use of the analgesic drugs.

4

The Journal of Kampo, Acupuncture and Integrative Medicine (KAIM)

Volume 5, Number 1 | Spring 2010

Conclusion
Electroacupuncture treatment may be a usefulcomplementary and alternative medicine for
acute postoperative pain management.
Acknowledgements
This work was supported by a grant forscientific research from the Ministry of Education
Science and Culture of Japan (0977076),
1998-1999.
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