From the Guidelines
Peripheral veins can be difficult to access due to various factors, and the use of ultrasound guidance is recommended to improve success rates and reduce complications. According to the most recent and highest quality study 1, ultrasound guidance can be useful when peripheral veins are difficult to visualize, especially in patients with obesity, drug abusers, and infants. The study found that overall success rate, median attempts, and time to catheterization were improved with ultrasound guidance.
Factors Contributing to Difficult Vein Access
- Dehydration
- Small vein size
- Deep vein placement
- Excess body fat
- Genetic factors affecting vein size or placement
- Medical conditions like low blood pressure or certain medications
Recommendations for Improving Vein Visibility
- Stay well-hydrated before blood draws or IV insertions to increase blood volume and make veins more prominent
- Apply warmth to the area for 5-10 minutes to dilate veins by increasing blood flow
- Let your arm hang down below heart level for a minute or two to help veins fill with blood and become more visible
- Consider mentioning difficulty with blood draws to healthcare providers in advance so they can use specialized techniques or equipment like ultrasound guidance to locate veins more effectively
Ultrasound Guidance for Vascular Access
The use of ultrasound guidance for vascular access has been shown to be cost-effective and improve outcomes, with a reduction in major complications and access time 1. It is recommended that ultrasound guidance be used routinely in adults when trained operators are available, especially when the pulsation of the artery is not evident, or when the artery is small.
From the Research
Difficult Peripheral Vein Access
There are several reasons why peripheral veins may be difficult to access. Some of the possible causes include:
- Obesity, which can make it harder to locate and access veins 2, 3
- Advanced age and/or complex disease, which can increase the vulnerability of patients and make vascular access more challenging 2
- Previous difficulties with venous access, which can lead to scar tissue and make it harder to access veins in the future
- Anatomical variations, which can make it harder to locate and access veins
Use of Ultrasound Guidance
Ultrasound guidance can be used to facilitate difficult peripheral venous access 2, 3, 4, 5. This technique involves using ultrasound imaging to guide the insertion of the catheter or needle into the vein. The use of ultrasound guidance has been shown to increase the success rate of peripheral venous cannulation, especially in patients with difficult access 5.
Benefits of Ultrasound Guidance
The benefits of using ultrasound guidance for peripheral venous access include:
- Increased success rate of cannulation 5
- Reduced risk of complications, such as catheter-related infections and venous thrombosis 2
- Reduced risk of catheterization failure 2, 3
- Potential to avoid more invasive procedures, such as central or intraosseous vascular access 3
Indications for Ultrasound-Guided Vascular Access
Ultrasound-guided vascular access may be indicated in patients who have difficult venous access, including those with:
- Obesity 2, 3
- Advanced age and/or complex disease 2
- Previous difficulties with venous access
- Anatomical variations that make it harder to locate and access veins
Current Evidence
The current evidence suggests that ultrasound guidance is a useful tool for facilitating difficult peripheral venous access 2, 3, 4, 5. Further research is needed to fully understand the benefits and limitations of this technique, but the available evidence suggests that it can be a valuable addition to traditional methods of vascular access.