Ultrasound Guidance Flashcards

A nurse using Doppler ultrasound observes color flow moving away from the probe shown in blue. This color coding represents:

Answer: Flow moving away from the probe

In standard color Doppler, blue represents flow moving away from the probe, while red represents flow toward the probe (BART: Blue Away, Red Toward).

Which ultrasound finding is most consistent with deep vein thrombosis (DVT) in an upper extremity vein?

Answer: Hyperechoic intraluminal material with non-compressibility

DVT typically appears as echogenic (hyperechoic) intraluminal material and the vein fails to compress under probe pressure.

When using the short-axis (transverse) ultrasound view for needle guidance, what is the main limitation compared to the long-axis view?

Answer: The needle tip cannot be distinguished from the shaft

In the short-axis view, only a cross-section of the needle is seen, making it difficult to confirm whether the needle tip or shaft is visualized at any given moment.

A patient's basilic vein measures 3 mm in diameter on ultrasound. According to best practice guidelines, this vein is:

Answer: Too small for PICC placement per standard guidelines

Standard PICC insertion guidelines recommend a minimum vein diameter of at least 4–5 mm to reduce thrombosis risk and allow for adequate catheter-to-vein ratio.

During ultrasound-guided PICC placement, posterior wall puncture is confirmed when:

Answer: Blood return is absent and the needle tip is visualized exiting the deep vessel wall

Posterior wall puncture occurs when the needle passes through both vessel walls; ultrasound shows the tip beyond the deep vessel wall and blood return may be absent or minimal.

Which ultrasound probe frequency range provides the best resolution for superficial peripheral veins used in vascular access?

Answer: 7.5–15 MHz

High-frequency probes (7.5–15 MHz) provide optimal resolution for superficial structures like peripheral veins, though at reduced depth penetration compared to lower frequencies.

When repositioning a patient's arm during ultrasound scanning to improve basilic vein visualization, which position typically optimizes access?

Answer: Arm abducted 45–90 degrees with elbow slightly flexed

Abducting the arm 45–90 degrees with slight elbow flexion typically distends the basilic vein and improves both visualization and needle access.