Dynamic SAX vs Conventional LAX in Radial Artery Cannulation.

Study Overview
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Brief Summary
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When performing vascular cannulation such as radial artery cannulation, ultrasonography (US) helps proper positioning of the tip of needle in the vascular lumen, which facilitating cannulation of the catheter and successful pressure monitoring. Conventionally, short-axis out-of-plane (SAX) and long-axis in-plane (LAX) views are commonly used method to image the target vessel during cannulation under US guidance. Dynamic needle tip positioning (DNTP) method is newly introduced by one group of investigators who conducted a related study using vascular phantom model. In DNTP, SAX is used, and additionally, when the needle tip is imaged in the screen as an echogenic point, the practitioner (a) proximally moves the US probe a bit, and then (b) the needle is advanced until the needle tip reappears in the screen. In this manner, the practitioner repeats (a) and (b) until the needle is inserted 1 cm into the lumen of vessel, and then the catheter is inserted to finish the procedure. DNTP has not been compared to conventional imaging methods. The aim of this trial is to see the effect of DNTP on success rate of the radial artery cannulation at the first attempt, compared to the conventional LAX.

Official Title
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Randomized Trial of Ultrasound-guided Radial Artery Cannulation Using Dynamic Short Axis Versus Conventional Long-axis In-plane View in Cardiac Surgery Patients.

Conditions
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Cardiac Surgical Procedures, Catheterization, Ultrasonography

Intervention / Treatment
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* Procedure: Dynamic needle tip positioning under ultrasound-guidance
* Procedure: Conventional long-axis view


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Elective cardiovascular surgery where RA catheterization is newly required. Exclusion Criteria: skin infection or trauma Bilateral arteriovenous fistula for dialysis Severe peripheral vascular disease Severe arteriosclerosis or arterial atheroma Raynaud disease Shock Patients on ECMO or IABP support Morbid obesity Profound coagulopathy Negative results of modified Allen's test

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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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Other
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Dynamic needle tip positioning<br>In DNTP, SAX is used, and additionally, when the needle tip is imaged in the screen as an hyper-echoic point, the practitioner (a) moves the US probe proximally a bit, and (b) the needle is advanced until the needle tip reappears in the screen. In this manner, the practitioner repeats (a) and (b) until the needle is inserted 1 cm into the lumen of vessel, and then the catheter is inserted to finish the procedure. | Procedure: Dynamic needle tip positioning under ultrasound-guidance<br>* The tip of needle is positioned under ultrasound-guidance using dynamic short-axis view.<br>|
| Active Comparator: Conventional long-axis<br> | Procedure: Conventional long-axis view<br>* The tip of needle is positioned under ultrasound-guidance using conventional long-axis in-plane view.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Success rate of the radial artery cannulation at first attempt | Successful confirmation of the arterial waveform through a pressure monitor at first attempt of the radial artery cannulation | intraoperative | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Time between skin puncture to confirmation of the arterial waveform through a pressure monitoring device. |  | During the cannulation procedure. |