Transcutaneous Electrical Nerve Stimulation for Labor Pain Control in Combination With Cardiotocography

Study Overview
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Brief Summary
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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 TENS1 alternating between 4 to 100 Hz compared to sham-TENS. The present study aims to evaluate TENS in combination with cardiotocography (CTG). The combination of TENS with CTG in a feedback-loop has not been reported in any studies before.

Detailed Description
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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 screening questionnaire about the laboring parturient in cooperation with the subject and the 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 outcomes (VAS and PPT). The subjects will be exposed to one of the two combinations of TENS stimulation (low-to-high and high alternating frequency), which will be compared to sham-TENS.

Official Title
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Transcutaneous Electrical Nerve Stimulation for Labor Pain Control in Combination With Cardiotocography

Conditions
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Labor Pain

Intervention / Treatment
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* Device: DS5 electrical stimulator


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Singleton pregnancy Vertex presentation Speak, read and understand Danish Exclusion Criteria: Gestational age < 37+0 weeks Gestational age > to 41+6 weeks High-risk pregnancies (including risk factors: eclampsia, pre-eclampsia, diabetes, gestational diabetes, hypertension (above 140/90), and hypotension (below 90/60), Intrauterine growth restriction (IUGR), polyhydramnious, and oligohydramnious). Pre-gestational body mass index (BMI) above 40 kg/m2 Use of fetal scalp-electrode during the experiment Use of pacemakers and other electronic implants Severe arrhythmia Present musculoskeletal illnesses (including myopathy and arthritis). Chronic pain within last 6 months (Pelvic girdle pain (PGP) to a mild degree (VAS 0-6 cm) is accepted in the experiment. Severe degree (VAS 6-10 cm) (e.g. bedridden or difficulty walking) especially within 24 hours before birth is excluded). Present/previous neurologic illnesses (including epilepsy, migraine, and sclerosis). Present medicated mental disorders (including dementia, personality disorders, bipolar, ADHD, and anxiety). Dermatological disorders (including skin allergy, tattoos or scars on the locations of electrodes) Use of other long-acting pain relief before the experiment (including Epidural, Morphine less than 16 hours before experiment), Acupuncture, Paracetamol (less than 8 hours before experiment), Cocktail (less than 8 hours before experiment), nitrous oxide (less than one hour before experiment), sterile water injection (less than two hours before experiment). Use of TENS 48 hours before the trial Drug addiction defined as the use of cannabis, opioids or other drugs. Smokers Lack of ability to cooperate

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Parallel Assignment
Interventional Model Description: 2 groups (TENS and sham)
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: TENS<br>TENS with 4/100 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?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| 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 | 
| Pain pressure threshold (PPT) | 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
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Keywords Provided by Centre Hospitalier Valida
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TENS, Labor pain, Childbirth, RCT, Pilot study