Comparison of Entonox and Transcutaneous Electrical Nerve Stimulation (TENS) in Labor Pain

Abstract

One of the concerns among mothers for delivery is labor pain. There are various methods to decrease labor pain, of which epidural anesthesia is an effective one, but not all mothers agree to receive this invasive intervention. Transcutaneous electrical nerve stimulation (TENS) is an inexpensive, safe, and easily applicable method which can be used in patient control mode. To find proper non-invasive methods to pain relief during labor this study was conducted to compare TENS, Entonox and combination of them during the first phase of labor. In this RCT study, 120 pregnant women in the age range of 20-40 years, singleton pregnancy, at 37-42 weeks’ gestation, at cervical dilatation of less than 4 cm in phase one of labor were selected and randomly divided into three groups including TENS, Entonox and combination group. Pain severity was recorded based on VAS at the time of presentation to the maternity unit, cervical dilatations of 4-6cm, 6-8cm, and 8-10cm and demographic characterizations. There were no significant differences regarding to age, parity, and BMI between the three groups. Pain was less severe in combination group compared to other two groups at cervical dilations of 4-6cm and 6-8cm. At cervical dilation of 8-10cm, VAS score was higher in Entonox group than in other two groups, but no significant difference existed between TENS and combination group. Duration of the first phase of labor was longer in TENS group than the other two groups. TENS is a non-invasive, safe, easy applicable and self-administered method with low rate of complications which can be used alone or in combination with other methods in relieving labor pain.Journal of Medical and Biomedical Sciences (2017) 6(2), 11-16

Applying a physiotherapy protocol to women during the active phase of labor improves obstetrical outcomes: a randomized clinical trial

“…A study by Chaichian et al 28 revealed a shorter active phase of labor for women who remained immersed in warm water throughout labor than for those who received conventional care. 29 …”

A novel technique combining transcutaneous electrical nerve stimulation with external tocography for personalized automated labor pain control

“…The frequently used type of sham-TENS was inactive units (in 11 out of 13 studies), though this method is prone to bias as it is not clear if the parturient or the investigator were blinded to the treatment. Since the Cochrane review, several RCTs have been published in which 5 out of 7 studies were graded +++ on GRADE (28,64,75,117,119).…”

“…In Study II and Study III, several improvements could be made with respect to optimizing the placements of electrodes and parameters of TENS, including pulse duration and frequency. Therefore, it was decided to go for long pulse durations and individually adjusted intensity, which has proven effective in other studies (28,64,85,103,119). However, electrode placement in studies II and III was only achieved with one set of electrodes at the S2-S4 spinal level.…”

“…However, electrode placement in studies II and III was only achieved with one set of electrodes at the S2-S4 spinal level. Typically, the placements of electrodes also include T10-L1 (28,64,85,103,119). Though it was decided to stimulate close to the site of pain at the S2-S4 level in studies II and III, even though S2-S4 is considered more involved in the second stage of labor.…”