Pulmonary Artery Pressure vs. Pulmonary Artery Wedge Pressure

[Jedi of Zen]

Does anyone know a down-and-dirty way to explain the difference?

Thanks!

[Daytonite, BSN, RN]

Pulmonary artery pressure is a physiological happening in the heart; wedging (with Swan-Ganz catheters) is a medical procedure that was developed to make measures of the pulmonary artery pressure from directly inside the pulmonary artery.

[Jedi of Zen]

Pulmonary artery pressure is a physiological happening in the heart; wedging (with Swan-Ganz catheters) is a medical procedure that was developed to make measures of the pulmonary artery pressure from directly inside the pulmonary artery.

Would you say that "pulmonary artery pressure" is an arbitrary term, then?

[hypocaffeinemia, BSN, RN]

Does anyone know a down-and-dirty way to explain the difference?

Thanks!

Pulmonary Artery Pressure is exactly what you'd think it'd be: Pressure inside the pulmonary arterial system.

Wedge pressure is effectively monitoring the pressure of your left atrium, even though the probe is located inside the pulmonary artery. This is a useful reading to monitor left ventricular failure, as pressure would back up to it.

Basically, using the same catheter, when the balloon at the end is deflated you are measuring the PA pressure-- pressure of the blood running by it. When you inflate it, and wedge it into place, you're measuring the back pressure (you've effectively cut off forward blood flow).

[RedCell]

Would you say that "pulmonary artery pressure" is an arbitrary term, then?

No it is not an arbitrary term.

When someone simply uses the term pulmonary artery pressure they are usually referring to mean pulmonary artery pressure as it relates to pulmonary hypertension. Pulmonary artery wedge pressure reflects left ventricular end diastolic pressure (LVEDP). Basically, that term can be simplified as preload (the amount of blood in the left ventricle prior to contraction). Wedge pressure is the same as LVEDP, PAOP, LADP, LVEDV and PAD barring that the patient does not have mitral stenosis, aortic regurgitation, elevated alveolar pressure or some kind of pulmonary venous obstruction.

PAOP= Pulmonary artery occlusive pressure LADP=Left atrial diastolic pressure LVEDV=Left ventricle end diastolic volume PAD=Pulmonary artery diastolic pressure

To be practical, pulmonary artery catheters are being used less currently as there are other technologies that are not as invasive. Also, if you look at the research, there is much controversy over whether any improvement in patient outcome can be found in the placement of the vast majority of PA catheters. I am sure Dr. Swan and Dr. Ganz would disagree with the previous statement however:D