Transcutaneous Electrical Nerve Stimulation for Labor Pain Control

Study Overview
=================
Brief Summary
-----------------
Transcutaneous electrical nerve stimulation (TENS) is a non-invasive electro-physical modality used for several pain conditions including labor pain control. Despite several years of research, there is still no agreement within the literature regarding the selection of TENS parameters. It is aimed to investigate two types of TENS frequencies (TENS1 alternating between 4 to 100 Hz and TENS2 alternating between 80 to 100 Hz) compared to sham-TENS.

Detailed Description
-----------------
Midwives and the study investigator will ask parturients, who are admitted to the labor ward at Region Hospital Herning satisfying the inclusion and exclusion criteria, whether they are interested in attending the experimental session. The study will be conducted as soon as the subject is admitted at the labor ward. The study will only be conducted during early and active labor and not during the birth of the baby. The subject in this study includes the package of a parturient and her neonate (after birth) as we also obtain data about the neonate. Hereby, two consent forms will be obtained. As this study is a non-invasive study, it is decided to have at least the consent of one parent. The investigator will fill out a questionnaire about the parturient in cooperation with the subject and midwife, including screening questions related to inclusion and exclusion criteria before the experimental session starts. The study will last approximately one hour and will be conducted during laboring circumstances. KT (Kenoja Thuvarakan) will carry out the experiment, and she will be present in the delivery room during the whole session. The study includes several outcomes, including subjective and semi-objective pain measures. The primary outcome is VAS (0-10 cm scale), while secondary outcomes include PPT and satisfaction questionnaire (only at the end of the study). The subjects will be asked before, and immediately after the experimental exposure about the four outcomes (VAS and PPT). The subjects will be exposed to one of the two combinations of TENS stimulation (low and high alternating frequency), which will be compared to sham-TENS.

Official Title
-----------------
Transcutaneous Electrical Nerve Stimulation as a Pain-relieving Approach in Labor Pain Control: a Randomized Double-blinded Controlled Pilot Study

Conditions
-----------------
Labor Pain

Intervention / Treatment
-----------------
* Device: DS5 electrical stimulator


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Singleton pregnancy Between ages 18-39 years Vertex presentation Speak, read and understand Danish At term (37-42 weeks gestation age) Exclusion Criteria: High-risk pregnancies (including risk factors: eclampsia, pre-eclampsia, diabetes, gestational diabetes, hypertension, and hypotension, intrauterine growth restriction, polyhydramnios, and oligohydramnios). Pre-gestational body mass index above 40 kg/m2 Use of fetal-scalp electrode during the experiment Use of pacemakers and other electronic implants Severe arrhythmia Present musculoskeletal/neurological illnesses Chronic pain within last 6 months Present medicated mental disorders Dermatological disorders Use of other long-acting pain relief Use of TENS 48 hours before the trial Drug addiction defines as the use of cannabis, opioids, or other drugs. Smokers Lack of ability to cooperate

Ages Eligible for Study
-----------------
Minimum Age: 18 Years
Maximum Age: 39 Years

Sexes Eligible for Study
-----------------
Female

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: 3 groups (TENS1, TENS2, and sham)
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: TENS1<br>TENS with 4/100 Hz in frequency, 200 µs in pulse duration, and intensity individually adjusted. | Device: DS5 electrical stimulator<br>* TENS<br>|
| Experimental: TENS2<br>TENS with 80/100 Hz in frequency, 200 µs in pulse duration, and intensity individually adjusted. | Device: DS5 electrical stimulator<br>* TENS<br>|
| Sham Comparator: Sham-TENS<br>Sham with 100 Hz in frequency, 200 µs in pulse duration, and intensity below 5 mA. | Device: DS5 electrical stimulator<br>* TENS<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in Visual Analog scale (VAS) | 10-cm pain intensity scale with 0 cm is no pain and 10 cm is unbearable pain. Decreased cm after baseline measurement indicates pain relief. | Baseline, 10 minutes post stimulation, 30 minutes post stimulation | 
| Change in Pain pressure threshold | Pain sensitivity measurement also defined as the minimum pressure needed to evoke a pain response measured in kPa. Increased kPa after baseline measurement indicates pain relief. | Baseline, 10 minutes post stimulation, 30 minutes post stimulation | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Satisfaction of TENS | Satisfaction rating on scale from 0 to 10 [0 as 'no satisfaction' and 10 as 'total satisfaction']. | Right after last measurements of VAS & PPT | 
| Experienced pain reduction | Response to yes or no | Right after last measurements of VAS & PPT | 
| Interest in the use of TENS again | Response to yes, no, or don't know | Right after last measurements of VAS & PPT | 
| Recommend TENS to others | Response to yes, no, or don't know | Right after last measurements of VAS & PPT | 

 Terms related to the study
=================
Keywords Provided by Centre Hospitalier Valida
-----------------
RCT, TENS, Labor pain, Childbirth, Pilot study