arterial waveform cascade

Focker, CRNA · Jun 14, 2007

pulsus paradoxus? Never heard of it referred to as the arterial cascade pattern though.

skipaway · Jun 14, 2007

You can evaluate hydration status by observing the arterial waveform and the SpO2 waveform. With an obvious up and down pattern, noting the downward pattern occurs during diastole, you can make the assumption the patient is dry. It has been years since I learned about this and I'll have to go try to find out the exact causes, but I still look for these cascades when I'm with a patient. Maybe this will help guide your search.

cardiacRN2006, ADN, RN · Jun 14, 2007

...,,

dfk, RN, CRNA · Jun 15, 2007

i also learned, thanks to anesthesia school, that the amplitude of the ECG can tell you something about fluid status. as for the arterial cascade, i have used the ECG cascade to get/keep baseline rhythm at start of case, but perhaps the arterial cascade is similar and allows the ability to detect fluid status intra-op?

ralatek · Jun 15, 2007

The way it was explained to me was that during PPV, intrathoracic pressure increases and venous return to the R heart decreases thereby decreasing LV preload and hence, decreasing arterial blood pressure. During periods of hypovolemia this up and down tracing of the a-line waveform becomes more apparent and can be used as a rough estimate of volume status. I've tried to reference this explanation in a textbook with no luck. Any other opinions??

Nitecap · Jun 21, 2007

A-line wave form analysis

Upstroke - contractility

Down stroke - SVR, Volume status

Level of dicrotic notch - Volume status, SVR, norm should be in upper 1/3 of downstroke

Area under curve - Stroke volume

Respiratory variability - volume status.

Square wave tests - assess to see if under or over dampened