Question 11.2

The image below represents a tracing of an arterial waveform.

What procedure has been performed?

(b)        What is your impression of the fidelity of the arterial system? Give two (2) reasons.

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College Answer

What procedure has been performed?

Fast flush test

(b)        What is your impression of the fidelity of the arterial system? Give two (2) reasons.

Underdamped trace – Multiple oscillations and systolic overshoot

Discussion

The dynamic response testing of arterial lines is discussed in greater detail elsewhere.

In brief: the under-damped trace will overestimate the systolic, and there will be many post-flush oscillations.

Underdamped arterial line waveform

References

From Bersten and Soni's" Oh's Intensive Care Manual", 6th Edition; plus McGhee and Bridges Monitoring Arterial Blood Pressure: What You May Not Know (Crit Care Nurse April 1, 2002 vol. 22 no. 2 60-79 )

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