Tuesday January 3, 2006
Procedure Tip - Does that waveform look ‘wedged’?

Many a times, while placing a PA catheter we encounter waveforms that look ‘different’ and we are not sure if it’s the wedged waveform. Of course, you are going to get a CXR but it can only confirm the position and you still may not be sure if the PA catheter is wedged when the balloon is inflated! Here’s a tip.

Take 2 blood samples from the pulmonary artery port: One while the balloon is deflated (mixed venous sample) and the other while the balloon is inflated (wedged sample). If the wedged PaO2 exceeds the mixed venous PaO2, then the catheter is definitely in the wedged position when the balloon is inflated. Also compare the wedged PaO2 with arterial PaO2. If the values are almost identical, the catheter may be too far in. Do you still need the CXR!

Related:
PACEP: Pulmonary artery catheter education project.
P. A. Catheterization insertion video (from Edwards Lifesciences).
Invasive HDM Troubleshooting video (from Edwards Lifesciences).
Vigilance Monitor Inservice video (from Edwards Lifesciences).
Videos above need windows media player