Why should ultrasound be used for vascular access procedures?

Ultrasound-guided vascular access is a technique that improves the safety and success rate of invasive cardiovascular procedures. According to the American Institute of Ultrasound in Medicine’s practice parameters released in 2012, ultrasound-guided vascular access offers practitioners significant benefits such as increased procedural success and patient safety in invasive vascular procedures. Vascular access sites include but are not limited to the radial artery, upper extremity veins, jugular vein, fermoral artery, and brachial artery. Invasive cardiovascular practitioners, anesthesiologists, and others can benefit greatly from access to ultrasound equipment and periodic training in ultrasound-guided vascular access.  

The first mention of the use of ultrasound for setting up a vascular access traces back to 1987. It then took a decade to see recommendations on the matter in the UK, in the USA, and in France. The benefits of using ultrasound for vascular access quickly became obvious: increased success rate and reduced procedure time. In their standards published in 2011, the American Society of Echocardiography and the Society of Cardiovascular Anesthesiologists wrote, “Many studies have shown a clear advantage of ultrasound guidance over landmark guidance for IJ central venous cannulation.” These studies have displayed how the overall success rate of central venous cannulation can be improved from 96% to 100% with ultrasound use, noted the researchers. As a result of such advances, practitioners have also witnessed an increase in safety and comfort for patients.  

Ultrasound guidance decreases the complication rate 

One undeniable benefit of ultrasound is its ability to drastically reduce the complication rate in comparison to other techniques. In the past, vascular access was known to carry a significant risk of bleeding and nerve damage. However, with the introduction of ultrasound, clinicians are able to visualize the depth and diameter of vessels as well as find veins that are not visible or palpable. This increase in needle visualization during the procedure signifies that the risk of hitting unwanted structures is reduced. This achievement would not have been possible without ultrasound guidance as practitioners were forced to carry out the procedure “blind” in the past. 

It’s been proven that using ultrasound for vascular access delivers better results when dealing with the internal jugular vein, the subclavian vein, and the femoral vein. For example, the use of ultrasound during access of the jugular vein can allow the clinician to avoid accessing the carotid artery and other structures around the area. 

Ultrasound guidance can also help during peripheral or radial arterial catheterizations, though they are less risky by nature, by reducing patient pain and discomfort. Meanwhile, certain access routes actually require the use of ultrasound guidance, such as the upper arm veins and the popliteal artery. 

Furthermore, patients with obesity, poorly palpable pulses, edema, known vascular disease, and limited access options present a significant challenge when performing vascular access. In cases such as these, ultrasound-guided access is an excellent technique for improving the success rate and minimizing the risk of damaging unwanted vessels or structures. Additionally, ultrasound is considered essential when practitioners are looking to access non-palpable arteries such as the popliteal artery.  

Ultrasound and needle guides: a breakthrough for anesthesiologists 

Using ultrasound can be made even more effective when paired with a needle guide. The combination of ultrasound with a needle guide, such as the ProV Access, is extremely beneficial for practitioners and can make it easier and more efficient to access the internal jugular vein, the subclavian vein, the axillary vein, the cephalic vein, and the femoral vein. They are an ideal tool for improving success rates and facilitating cannulation. 

Practitioners can expect a series of benefits when employing a needle guide: 

• Decreased number of attempts: 1 with a needle guide, 2-8 without 
• Better needle or catheter visualization (the tip of the needle in particular) compared to ultrasound alone 
• Higher success rates: punctures are five times more successful at the first attempt with a needle guide 

As their name suggests, needle guides hold the needle in place during the procedure. By keeping it in line with the ultrasound probe, practitioners are given better control over the direction of the needle. The combination of increased visualization and control serves to minimize the risk of hitting and damaging areas around the access site. Clinical areas such as interventional cardiology can also benefit from the use of a needle guide when placing stents, PICC lines, or CVCs.

Long–axis (in-plane) and short–axis (out-of-plane) approaches 

Clinicians have two approaches at their disposal when conducting vascular access procedures. The plane of the ultrasound image can be oriented relative to the vessel in the long or short axis.  

When utilizing a short–axis approach, the clinician will have an image plane which is perpendicular to the vessel and to the needle. In this case, the needle is considered to be “out-of-plane.” Clinicians should see the vessel as an anechoic circle on the monitor with the needle appearing as a hyperechoic point in the cross section. 

In contrast, when using a long–axis view practitioners will have the image plane parallel to the course of the vessel. As a result, the needle is “in-plane” and the image should display the vessel on the monitor as well as the shaft and end of the needle as the clinician advances it to the target. 

Each approach has different advantages which the clinician must weigh in relation to the nature of the procedure. The long-axis view allows for visualization of the whole needle shaft and tip. It may be a more efficient and appropriate option for use with large vessels, although the short-axis approach remains an option if great care is taken to follow the location of the needle point. It is crucial that with these larger vessels, such as central veins, practitioners know where the tip of the needle is during the procedure. The short-axis approach permits the needle to be over the center of the vein, but clinicians must be cautious in fanning the plane of the image along the needle itself during the advance to follow the tip and minimize the risk of miscalculating its depth.  

Practitioners also have the option of starting a procedure with a short-axis approach and then transiting to a long-axis approach. The CathLab Digest notes, “It may be helpful to start a procedure with a short-axis view to ensure that the needle is centered over the middle of the vessel and then rotate the probe to a long-axis/in-plane view as the needle is advanced.” 

Overall, ultrasound-guided vascular access procedures are generally safe and have high success rates. Clinicians can experience more efficient procedures via the use of ultrasound as well as needle guides. There are a variety of resources at the disposal of healthcare professionals to further hone their skills in vascular access, such as practicing with a training phantom. Appropriate training is a key to delivering quality care, so it is paramount that practitioners remain up to date with the latest recommendations from regulatory bodies and advances in ultrasound imaging.

For more information about ultrasound-guided procedures or needle guides, please feel free to contact us or to visit this page

Thank you for reading us today!