Pain Perception During Chorionic Villus Sampling

Study Overview
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Brief Summary
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Chorionic villous sampling is a frequent procedure used for antenatal genetic testing. This procedure is associated with anxiety and fear of pain that can be expected during the procedure, often prejudicing patients against this definitive antenatal testing. It is important to determine if different approaches to pain and anxiety reduction are effective. Currently there is no randomized study to evaluate the efficacy of analgesia for pain reduction during chorionic villous sampling. Multiple studies have been published suggesting that analgesia during the similar procedure of amniocentesis does not significantly reduce pain scores.

Detailed Description
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Chorionic villous sampling (CVS) is a frequent procedure used for antenatal genetic testing. This procedure is associated with anxiety and fear of pain that can be expected during the procedure, often prejudicing patients against this definitive antenatal testing. It is important to determine if different approaches to pain and anxiety reduction are effective. Previous studies have not shown that local anesthesia affects pain experience during amniocentesis (1-5). There are no randomized studies evaluating interventions for pain reduction during chorionic villous sampling which constitutes an important evidence gap. The study will be offered to women at <13 weeks gestation, with a singleton fetus who are seen at Mount Sinai Medical Center for chorionic villous sampling. The eligible women will be randomized to one of two groups: use of analgesia using injectable lidocaine or ethyl chloride topical anesthetic spray. This study intends to show that local anesthesia during chorionic villous sampling will not decrease the perception of pain in patients undergoing this procedure. This trial is trying to determine perception of pain based on use of injectable lidocaine or ethyl chloride anesthetic spray; it is noted that the form of anesthesia may be a factor in perception of pain. The investigators do not know if there is a difference in perception for topical or injectable. If the perceived pain is comparable in topical and injectable, this trial could conclude that both are viable options, and while both present minimal risk to patients, topical is less invasive.

Official Title
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A Randomized Trial to Determine if Local Anesthesia Decreases Pain Perception in Women Undergoing Chorionic Villus Sampling

Conditions
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Chorionic Villi Sampling

Intervention / Treatment
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* Drug: Lidocaine injection
* Drug: Gebauer Ethyl Chloride Spray


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: <13 week gestation Singleton gestations undergoing CVS Exclusion Criteria: Multiple gestations More than one attempt of needle insertion Allergy or hypersensitivity to local anesthesia

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 65 Years

Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

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
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Lidocaine Injection<br>Injection of lidocaine which is given prior to chorionic villus sampling | Drug: Lidocaine injection<br>* Injectable anesthesia is 1-2mL of 2% lidocaine via a 22 gage needle, given at the anticipated site of CVS needle puncture immediately before procedure.<br>|
| Experimental: Gebauer Ethyl Chloride Spray<br>Topical anesthesia will be Gebauer Ethyl Chloride sprayed continuously from 3 - 7 seconds from a distance of 3-9 inches until the skin turns white (not frosting the skin) as per Gebauer package insert instructions. | Drug: Gebauer Ethyl Chloride Spray<br>* Gebauer Ethyl Chloride Spray is a topical anesthetic spray which is sprayed continuously for 3-7 seconds from a distance of 3-9 inches at the site where the chorionic villus sampling is expected to take place.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Visual Analog Scale (VAS) Pain perception scores VAS () | Procedure pain perception score as measured by the visual analog scale. By means of analysis of the receiver operating characteristic curves on a 100mm VAS: no pain 0-2 mm, mild pain 2-17 mm, moderate pain 17-47 mm, severe pain 47-77 mm, very severe pain 77-96 mm, most severe pain imaginable 96-100 mm | day 1 | 
| Verbal Rating Scale (VRS) | Procedure pain perception score as measured by the Verbal Rating Scale. 0=no pain, 1=mild pain, 2=moderate pain, 3=severe pain, 4=very severe pain, 5=most severe pain imaginable | day 1 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Chorionic villus sampling, Pain, Anxiety