Peripheral Venous Access: Devices, Insertion, and Ultrasound Guidance
Domain 5: Peripheral Venous Access: Devices, Insertion, and Ultrasound Guidance
This domain tests selection and insertion of short peripheral catheters, including ultrasound rescue of difficult veins.
Core rules
- Choose the smallest gauge that meets flow and therapy needs; larger gauges do not automatically prevent phlebitis. Use distal sites first, and avoid flexion areas and areas with infection, oedema, or dialysis fistula.
- Aseptic technique: hand hygiene, clean gloves, skin antisepsis with chlorhexidine-alcohol and dry time, sterile dressing.
- Insertion: tourniquet, stabilise vein, enter at 15–30 degrees, observe flashback, lower angle, advance catheter off the needle, release tourniquet, connect, secure, and label with date and time.
- Ultrasound: identify vein and artery; use transverse view to centre, longitudinal or in-plane to track the needle tip. Confirm tip within lumen, not through the posterior wall. Avoid valves and bifurcations.
- Reassess after insertion: flow, pain, swelling, infiltration, and site security.
Worked example
A patient with chronic kidney disease needs IV antibiotics; no visible veins. Ultrasound shows a 3.5 mm cephalic vein at 0.8 cm. Reasoning: avoid the cubital fossa and any fistula arm. Use a 22G catheter, in-plane approach, track the tip, and confirm flashback. If flashback occurs but the catheter will not advance, do not force: release tourniquet, flush gently while advancing, or choose another site.
Traps
Blind probing; transfixing the vein; ignoring arterial puncture; using the antecubital fossa for vesicants; failing to label the device; and not checking distal perfusion.