Ultrasound guidance is now a key component of modern PICC insertion, supporting improved accuracy, higher success rates and reduced complications. Current guidance recommends its use wherever possible, particularly for upper arm insertion, reflecting its role in enhancing both safety and efficiency in vascular access.
Evidence consistently supports this approach. Studies have shown that ultrasound guidance improves first-attempt success rates, reduces placement failures and lowers complication risk. However, as with any technique, there is a learning curve, making structured training and competency development essential.
Basic Principles of Ultrasound
Ultrasound uses high-frequency sound waves, transmitted into the body via a probe (transducer). These waves reflect off internal structures and return to the probe, allowing the machine to create a real-time image.
In simple terms:
- Sound waves are sent into the body
- They reflect off tissues and vessels
- The returning signals are converted into a visual image
This enables clinicians to visualise anatomy dynamically during PICC insertion.
Using the Transducer Effectively
The transducer both sends and receives sound waves, producing a thin image slice of the target area. Correct orientation is essential, as misalignment can lead to confusion when interpreting images.
Two main approaches are used:
- Transverse view: the vessel appears round and supports initial identification
- Longitudinal view: the vessel appears as a line, allowing needle tracking
Keeping the needle within the ultrasound beam at all times is critical for safe and accurate placement.
Vessel Identification
Ultrasound makes it easier to distinguish between veins and arteries:
- Veins: compressible, non-pulsatile and typically larger
- Arteries: pulsatile and non-compressible
A vein that does not compress may indicate thrombosis and should not be used.
Optimising Image Quality
Image clarity is influenced by:
- Frequency: higher frequencies give better detail for superficial vessels
- Gain: adjusts brightness to improve visibility
Proper probe preparation is also essential. Ultrasound gel must be used to ensure effective transmission of sound waves, and air bubbles must be avoided to maintain clear imaging.
Practical Technique Considerations
Common challenges when learning ultrasound include:
- Watching hands instead of the screen
- Applying too much pressure and collapsing the vein
- Poor probe control or incorrect needle angle
To support best practice:
- Move slowly and deliberately
- Keep the vessel and needle centred on the screen
- Regularly check positioning throughout the procedure
Simulation training and routine use of ultrasound can help build confidence and consistency.
Conclusion
Ultrasound guidance has become central to best practice in PICC insertion. By improving visualisation and supporting more precise technique, it helps reduce complications and improve patient outcomes.
With appropriate training and consistent use, ultrasound enables clinicians to deliver safer, more reliable vascular access as part of modern, patient-centred care.
