Ultrasound-guided Versus Direct Palpation Radial Artery Catheter Insertion Among Cardiac Anesthesiologists

Study Overview
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Brief Summary
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When a patient undergoes heart surgery, their Anesthesiologist will insert a tiny plastic tube, called a catheter, in the artery of the patient's wrist. This is called a radial artery catheter. A radial artery catheter allows accurate measurement of the patient's blood pressure during surgery. There are two common techniques for placing the radial artery catheter. The first is a blind technique whereby the Anesthesiologist feels for the pulse in the patient's wrist and places the catheter using the location of the pulse as a guide. The second technique, less commonly used, is one whereby the Anesthesiologist uses an ultrasound machine (painless to the patient) to see the artery, and thereby uses the ultrasound to guide the catheter placement. Our study will test the hypothesis that ultrasound-guided radial artery catheterization will have faster insertion times, with fewer complications compared with palpation-guided insertion.

Official Title
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A Comparison of Ultrasound-Guided Versus Direct Palpation For Radial Artery Catheterization Among Cardiac Anesthesiologists

Conditions
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Time to Insertion of Radial Artery Cannulation

Intervention / Treatment
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* Device: Ultrasound-guided Radial Artery Catheter Insertion
* Device: Direct Palpation-guided Radial Artery Catheter insertion


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients undergoing cardiac surgery Age 19 or older Provided written informed consent Exclusion Criteria: Suspected inability to comply with study procedures, including language difficulties or medical history and/or concomitant disease, as judged by the investigator Previous surgery at the site of proposed radial artery catheterization Any vascular condition that may preclude eligibility for radial artery line insertion as judged by the investigator Patients with ventricular assist devices Previous inclusion in this study

Ages Eligible for Study
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Minimum Age: 19 Years

Sexes Eligible for Study
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All

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: Prevention
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Single


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: direct palpation<br>Radial artery catheter insertion will be conducted by direct palpation and use of anatomic knowledge by the Anesthesiologist. | Device: Direct Palpation-guided Radial Artery Catheter insertion<br> <br> |
| Active Comparator: Ultrasound<br>Radial artery catheter insertion will be conducted by ultrasound guidance. A Sono-site ilook 25 Ultrasound (Sono-site, Inc., Bothell, WA, USA) with a 10-5 MHz linear array ultrasound transducer will be used. At the discretion on the Anesthesiologist, an out-of-plane (i.e. needle plane at right angles to ultrasound plane) will be used. Colour flow doppler may also be used to identify the artery if necessary. | Device: Ultrasound-guided Radial Artery Catheter Insertion<br> <br> |

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time to Successful Radial Arterial Catheterization | The time to successful radial arterial catheterization was defined as time zero to time of placement. Time zero for the DP group began when the anesthesiologist's fingers were placed on the patient with the purpose of palpating the artery. Time zero for the US group began when the US transducer was first placed on the patient's skin for the purpose of identifying the radial artery. Time to placement was defined as the interval from time zero until the time at which an arterial tracing was viewed on the monitor. | up to 5 minutes | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Number of Attempts | An attempt was defined as a new purposeful penetration of the skin with the needle (i.e., following complete withdrawal of the needle from the skin). | up to 5 minutes | 
| Number of Re-directions | A re-direct was defined as the needle being purposefully withdrawn at least 5 mm and re-directed (but not removed from the skin entirely). | up to 5 minutes | 
| Complication Rate (Hematoma) | A hematoma was defined a collection of blood or formation of a bruise surrounding the site of radial artery catheterization | up to 5 minutes |