Objective To observe the effect of transcutaneous electrical acupoint stimulation(TEAS)on ileus-postoperative gastrointestinal functions and plasma ghrelin

motilin

and gastrin contents

and heart rate variability(HRV)in patients undergoing gastrointestinal surgery

so as to explore the interaction of vagus-brain-gut peptide.Methods A total of 58 patients undergoing elective gastrointestinal surgery were randomly assigned to TEAS(n=29)and sham-TEAS group(n=29

patients had no subjective sensation to 1mA TEAS

thus

being considered to be sham-TEAS).TEAS(2Hz/100 Hz

6-8mA for LI 4-PC 6

12-18 mA for ST 36-SP 6)was applied to bilateral Hegu(LI 4)-Neiguan(PC 6)from 30 min pre-operation to the end of the operation and to bilateral LI 4-PC 6and Zusanli(ST 36)-Sanyinjiao(SP 6)for 30 minutes twice daily in 3consecutive postoperative days.ECGs of 12 leads were recorded to analyze different parameters of HRV from 2days before and 4days after surgery.Plasma ghrelin

motilin and gastrin contents were assayed by radioimmunoassay

and the patients' first bowel sound

first independent walk

first flatus

first solid food-intake and first defecation were recorded to evaluate the recovery state of gastrointestinal motility.Results Postoperative gastrointestinal motility:compared with the sham-TEAS group

the first bowel sound and the first defecation after surgery appeared apparently earlier in the TEAS group(P<0.05)

but no significant differences were found between the two groups at the time of the first independent walk

first flatus and the first solid food-intake in patients undergoing gastrointestinal surgery.Plasma brain-gut peptides:the plasma ghrelin and motilin contents 4days post-surgery were significant increased in the TEAS group than in the sham-TEAS group(P<0.05).No significant difference was found between the two groups in plasma gastrin contents(P>0.05).HRV domains:in comparison with pre-surgery

the levels of low frequency(LF)and high frequency(HF)of frequency domain(FD)and root mean square of successive differences(rMSSD)of the time domain(TD)of HRV 4days after surgery were significantly decreased in the sham-TEAS group(P<0.05)

but no significant changes were found in both FD and TD domains of the TEAS group 4days after surgery(P>0.05).Compared with the sham-TEAS group

the HF and rMSSD levels were significantly increased in the TEAS group 4days after the surgery(P<0.05).No significant differences were found between the two groups in the levels of very low frequency

LF and LF/HF levels of FD

and standard deviation of NN(beat-to-beat)intervals

the standard deviation of the average NN intervals and the proportion of NN 50(the number of pairs of successive NNs that differ by more than 50ms)divided by total number of NNs of TD.Conclusion TEAS can promote gastrointestinal activities(i.e.

reducing the time spending of first bowel sound and the first defecation)in gastrointestinal surgery patients

which may be related to its effects in up-regulating ghrelin and motilin contents and parasympathetic activity.