A-line analysis

Q: All of the following may give under-damping of an arterial line EXCEPT?

A) excessive tubing length

B) tachycardia

C) high cardiac output

D) hypothermia

E) arterial spasm

Answer: E

An arterial line placement (A-line or Art-line) is one of the most common procedures in ICU. Said that it can mislead a physician if not interpreted properly. There are various factors that can either be an "over-damped" or an "under-damped" arterial line. A few common causes are below:

Over-damping (not very well formed waveform)

• air bubbles in the tubing 
• clots in the tubing
• loose connections
• kinks in the tubing
• arterial spasm

Under-damping (systolic pressure overshoot)

• excessive tubing length
• tachycardia
• high cardiac output
• hypothermia

#procedures

#cardiovascular

Reference:

Esper SA, Pinsky MR. Arterial waveform analysis. Best Pract Res Clin Anaesthesiol. 2014 Dec;28(4):363-80. doi: 10.1016/j.bpa.2014.08.002. Epub 2014 Sep 6. PMID: 25480767.