Ethyl Chloride Vapocoolant as Anesthesia for Arterial Punctures

Study Overview
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Brief Summary
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Ethyl chloride vapocoolant sprays provide transient skin anesthesia within seconds of application. The current investigation aim is to compare the effect of ethyl chloride based vapocoolant spray to placebo in reducing pain associated with arterial puncture for gasometry determinations. The investigators will conduce a double-blind randomized placebo-controlled trial at Emergency Department. We will enroll patients who come to Emergency Department who need an arterial gasometry determination. Patients will be randomized to intervention-group (ethyl chloride vapocoolant sprays will be usad before arterial puncture) or to placebo-group (alcohol spray as placebo will be used before arterial puncture.) and after the puncture they will rate their pain using a 10 points visual analogue scale.

Detailed Description
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Single-blind, randomized placebo-controlled trial in an emergency department of Hospital de Basurto in Bilbao, Spain. Patients for whom arterial blood gas analysis had been ordered will be included. They will be randomly assigned to receive application of the experimental ethyl chloride spray or a placebo aerosol spray of a solution of alcohol in water. The assigned spray will be applied just before arterial puncture. The main outcome variable is pain intensity reported on an 11-point numeric rating scale.

Official Title
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Ethyl Chloride Vapocoolant as Anesthesia for Arterial Punctures: A Randomized Clinical Trial

Conditions
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Anesthesia, Pain

Intervention / Treatment
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* Drug: Ethyl chloride
* Drug: Alcohol


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: age: 18-85 years old. arterial gasometry determination needed III, IV or V level classification on Manchester triage. Exclusion criteria: refusal to participate, inability to provide informed consent (non-Spanish speaking, dementia or altered mental state), skin disease associated with cold intolerance (Raynaud's phenomenon), known allergy to spray contents, Glasgow Coma Scale <15, pregnancy, under effects of alcohol or drugs, Allen test +.

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 85 Years

Sexes Eligible for Study
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All

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
Masking: Double


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Control<br>Alcohol -based spray as placebo will be administrated before arterial puncture. | Drug: Alcohol<br>* Nurses will use an alcohol-based spray as placebo on patient's skin a few seconds before arterial puncture (of cubital arteria).<br>* Other names: Placebo;|
| Experimental: Ethyl chloride<br>Ethyl choride will be administrated before arterial puncture. | Drug: Ethyl chloride<br>* Nurses will administrate ethyl chloride vapocoolant spray on patient's skin a few seconds before arterial puncture (of cubital arteria).<br>* Other names: Intervention;|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Pain Level on the Visual Analog Scale (NRS-11) | patients will measure their pain score on a visual analog scale (NRS-11: Numeric Rate Score, from 0 -no pain- to 10 points -the worst pain ever-) after the puncture | scores on a scale immediately after the puncture |