The Application of Analgesia Nociception Index as an Objective Labor Pain Assessment During Epidural Analgesia

Study Overview
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Brief Summary
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Epidural analgesia is considered an effective and safe method for obstetric pain control. Currently, self-assessment pain scales remain to be the gold standard in labor pain evaluation after the administration of epidural analgesia. However, individual patient susceptibility to pain perception makes difficulties for the clinicians to assess the effectiveness of painless labor precisely. The aim of this study is to evaluate the validity of ANI in obstetric pain monitoring during epidural analgesia.

Detailed Description
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Epidural analgesia is considered an effective and safe method for obstetric pain control. Currently, self-assessment pain scales remain to be the gold standard in labor pain evaluation after the administration of epidural analgesia. However, individual patient susceptibility to pain perception makes difficulties for the clinicians to assess the effectiveness of painless labor precisely. Without a convincing objective tool for obstetric pain evaluation during epidural analgesia, the clinicians are hard to adjust adequate epidural drug dosage. Establishing an objective pain index would help the clinicians to have a better pain management during labor. In 2012, M. Le Guen et al. demonstrated a linear relationship between visual analogical pain scores(VAS) and Analgesia Nociception Index (ANI) values during labor. Their efforts started the application of ANI in obstetric pain monitoring. However, the reliability of ANI in obstetric pain monitoring under epidural analgesia have not yet been verified. The aim of this study is to evaluate the validity of ANI in obstetric pain monitoring during epidural analgesia.

Official Title
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Changhua Christian Hospital, Department of Anesthesiology

Conditions
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Labor Pain

Intervention / Treatment
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* Device: Analgesia nociception index


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Parturients with gestational age more than 35 weeks Ages between 20 to 50 Received epidural analgesia American Society of Anesthesiologists classification I or II. Exclusion Criteria: 1. Who refused to join the study 2. With a history of arrhythmia 3. American Society of Anesthesiologists (ASA)Classification >= III 4. With a history of cardiovascular, pulmonary, endocrine, neurologic or psychiatric disease 5.Using medications that affecting heart rate 6. Cannot understand the explanation of the study 7. High-risk gestation 8. Known fetal anomaly

Ages Eligible for Study
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Minimum Age: 20 Years
Maximum Age: 50 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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Arms and Interventions

| Intervention/Treatment |
| --- |
|Device: Analgesia nociception index|Monitor the maternity with Analgesia nociception index|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The correlation of subjective pain measurement by the VAS score and objective pain measurement by the ANI(Analgesia Nociception Index) score | The VAS(visual analog scale) score is a subjective measure for pain. Scores are recorded by making a handwritten mark by the patient on a 10-cm line that represents a continuum between no pain and worst pain. The score will be transferred to a 0-100 index by divided 10 with the distance from the starting point to the written mark (in centimeter) and multiplied by 100. The ANI (Analgesia Nociception Index) score is a 0-100 index derived from heart rate variability which was applied as an objective pain measurement. The larger the index indicated less pain. The correlation of the VAS score and the ANI score will be analyzed to verified the strength of the ANI score in evaluating labor pain during epidural analgesia. | 90 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| The correlation of uterine contraction strength measured by cardiotocography and the ANI (Analgesia Nociception Index) score | Uterine contraction strength was measured by external cardiotocography with a scare from 0-100.The ANI (Analgesia Nociception Index) score is a 0-100 index derived from heart rate variability which was applied as an objective pain measurement. The larger the index indicated less pain. The correlation of the uterine contraction strength and the ANI score will be analyzed to verified if the ANI score changing with related to uterine contraction. | 90 Minutes | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Analgesia nociception index, Painless labor, epidural analgesia