From the Guidelines
Palpation of the liver does not directly assist in locating intravenous (IV) access sites, but rather, the hepatojugular reflux test, which involves applying pressure to the liver, can help increase venous pressure and make veins more visible and distended, thereby improving the success rate of IV cannulation. This technique is especially useful in patients with poor venous access, such as those who are dehydrated, obese, or have a history of IV drug use 1. The increased venous pressure causes the veins to become more prominent and easier to visualize or palpate, allowing healthcare providers to locate difficult-to-find veins not only in the arms but also potentially in the hands, forearms, or other accessible locations.
Key Points to Consider
- The hepatojugular reflux test involves applying firm pressure to the right upper quadrant of the abdomen (over the liver) for about 10 seconds while observing the neck veins, particularly the external jugular vein.
- This technique is useful in patients with poor venous access, such as those who are dehydrated, obese, or have a history of IV drug use.
- The increased venous pressure caused by the hepatojugular reflux test can make veins more visible and distended, improving the success rate of IV cannulation.
- Healthcare providers should maintain the pressure for at least 10 seconds to achieve the maximum effect and should look for veins in various accessible locations.
Evidence-Based Recommendations
The most recent and highest quality study on this topic is not directly related to the use of palpation of the liver for locating IV access sites, but rather emphasizes the importance of ultrasound-guided vascular access in reducing complications and improving success rates 1. However, in the context of real-life clinical practice, the hepatojugular reflux test can be a useful technique for locating difficult-to-find veins, especially in patients with poor venous access. As noted in a study on ultrasound-guided central venous catheter placement, combining anatomical knowledge with ultrasound guidance can improve the success rate of vascular access procedures 1. Additionally, a study on liver biopsy highlights the importance of image-guidance in avoiding vascular or other structures, which can be applied to the context of IV access 1.
From the Research
Palpation of the Liver and IV Access Sites
- Palpation of the liver can assist in locating intravenous (IV) access sites by providing information about the liver's size, shape, and position, which can help guide the placement of central catheters 2.
- The liver's anatomy, including the location of the hepatic veins and inferior vena cava (IVC), is crucial in determining the best approach for IV access 3.
- Ultrasound-guided techniques, such as the transhepatic view, can be used to visualize the IVC and hepatic veins, allowing for more accurate placement of central catheters 2.
Anatomy of the Liver and IVC
- The retrohepatic segment of the IVC and the termination of the hepatic veins are important anatomical landmarks in locating IV access sites 3.
- The hepatic veins empty into the IVC, and the size and position of these veins can vary between individuals 3.
- Understanding the anatomy of the liver and IVC is essential for navigating the placement of central catheters and avoiding complications 4, 5.
Ultrasound-Guided Techniques
- Ultrasound-guided techniques, such as the transhepatic view, can be used to visualize the IVC and hepatic veins, allowing for more accurate placement of central catheters 2.
- The transhepatic view is preferred over the subxiphoid view for visualizing the IVC and localizing the catheter tip 2.
- Ultrasound-guided techniques can also be used to measure the hepatic venous pressure gradient (HVPG) and perform transjugular liver biopsies 6.