A Comparison Between Conventional and Waveform-Confirmed Loss-of-Resistance for Thoracic Epidural Blocks

Study Overview
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Brief Summary
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In the investigators' institution, the failure rate for thoracic epidural blocks is 23.1%. This stems from the prevalence of trainee operators coupled with the non-specific nature of loss-of-resistance. In the current randomized trial, we will set out to compare conventional and epidural waveform analysis-confirmed loss-of-resistance. The investigators' research hypothesis is that loss-of-resistance combined with epidural waveform analysis will decrease the failure rate of thoracic epidural blocks.

Official Title
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A Randomized Comparison Between Conventional and Waveform-Confirmed Loss-of-Resistance for Thoracic Epidural Blocks

Conditions
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Anesthesia

Intervention / Treatment
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* Procedure: Waveform-confirmed loss-of-resistance


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: the patients undergoing thoracic epidural catheter insertion for thoracic and abdominal surgery or rib fractures with American Society of Anesthesiologists (ASA) classification 1-3 and body mass index between 18 and 35 Exclusion Criteria: adults who are unable to give their own consent coagulopathy (assessed by history and physical examination and, if deemed clinically necessary, by blood work up ie platelets ≤ 100, or International Normalized Ratio ≥ 1.4) renal failure (assessed by history and physical examination and, if deemed clinically necessary, by blood work up ie creatinine ≥ 100) hepatic failure (assessed by history and physical examination and, if deemed clinically necessary, by blood work up ie transaminases ≥ 100) allergy to local anesthetic (LA) pregnancy prior surgery in the thoracic spine

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 80 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 |
| --- | --- |
| No Intervention: Conventional loss-of-resistance<br> | |
| Experimental: Waveform-confirmed loss-of-resistance<br> | Procedure: Waveform-confirmed loss-of-resistance<br>* Using waveform analysis to confirm thoracic epidural space<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Percentage of Patients With Successful Epidural Blocks | Fifteen minutes after the LA injection, a blinded observer will apply ice to the T1-L4 dermatomes and assess the epidural block. The criterion standard for success will be the presence of an epidural block (defined as a block to ice in at least 2 dermatomes bilaterally). If the operators cannot thread the catheter after 2 attempts, epidural blocks will considered failures. | up to 15 minutes after the procedure | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Epidural waveform analysis, Loss of resistance