Long-versus Short-Axis Ultrasound Guidance for Subclavian Vein Cannulation

Study Overview
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Brief Summary
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Central venous catheterization is commonly applied in patients undergoing cardiac surgery. The subclavian vein has lower risk of infection and provides more patients comfort. However central venous catheterization may results in complications such as pneumothorax, hemothorax or arterial puncture. It has been suggested that ultrasound (US) guidance could improve the success rate, reduce the number of needle passes and decrease complications. Two different real-time 2-dimensional US techniques can be employed in the insertion of central venous catheters. The first technique involves real-time US-guided cannulation of subclavian vein using a long axis/in-plane approach. The second one involves real-time US-guided using a short axis/out-off-plane approach. However to date no studies have compared their efficacy and safety. The purpose of this study was to compare the US-guided long-axis versus short-axis approach for the SCV catheterization in adult critical care patients.

Detailed Description
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The two techniques used for vessel visualization are far different: The Short-Axis (SA) approach attempts to view the vessel in cross-section while venous access is obtained. The strength of the SA approach is that the vein is centered under the transducer and that the midpoint of the transducer becomes a reference point for the insertion of the needle, and that at the same time is possible to visualize SC artery and the pleural line. SA approach is easy to learn by novice sonologists. The Long-Axis (LA) approach employs a technique that views the length of the vessel during cannulation.For this reason, with LA approach is possible to visualize the needle advance during the entire procedure from the soft tissues until the lumen of the vein, but SC artery and pleural line are not visualized in the same scan. For LA approach, practice is required to keep the needle precisely within the image and care must be taken to avoid the probe inadvertently moving away from the target structure.

Official Title
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Long-versus Short-Axis Ultrasound Guidance for Subclavian Vein Cannulation

Conditions
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Vascular Access Complication, Perioperative/Postoperative Complications

Intervention / Treatment
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* Device: Long Axis strategy
* Device: Short Axis Strategy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: aged =>18 years patients who needed central venous catheter for clinical reasons Exclusion Criteria: aged <18a years

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: Supportive Care
Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Active Comparator: Long Axis strategy<br>The central venous catheterization will be performed by the long axis approach | Device: Long Axis strategy<br>* With the long-axis approach the vein appeared in the longitudinal view. With this approach only the vein was visible on the screen. The needle was held at a 30° angle, oriented in-plane with the transducer and the skin punctured at the base of the transducer. The vessel alignment was maintained during the procedure and the entire length of the needle was visible during the progression through the tissues.<br>|
| Active Comparator: Short Axis Strategy<br>The central venous catheterization will be performed by the short axis approach | Device: Short Axis Strategy<br>* With the short-axis approach the probe was positioned almost perpendicularly to the clavicle. The needle was held at an angle of 45° relative to the skin surface and sagittal to the plane of the probe (out-of-plane). During the progression to the vessel, the visualization of the needle was limited to the deformation of tissue and artefacts produced by needle advancement. When the tip abutted the vein wall, additional pressure produced transient vessel deformation, which disappeared once the wall was penetrated.<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Success rate |  | up to 4 hours | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Access Time |  | Hours: 0,1 | 
| Central line-associated blood stream infection |  | days 0-21 | 
| Number of attempts | Overall number of skin penetration and number of withdraws and redirections of the needle | hours: 0-2 | 
| Complication rate | Pneumothorax, Haemothorax, Hydrothorax, Artery puncture, Hematoma, Malpositions | Hours: 0-6-12-24 | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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pneumothorax, central venous access, ultrasonography, subclavian vein, vessel view