Question about Cushing's

[Lorus]

Hey everyone-

I posted this question over on the neuro board, but its like a morgue over there...

Generally, as the ICP rises and results in cushing's response, the pulse pressure widens. Systolic goes up, diastolic goes down. I am wondering- what causes the diastolic pressure to drop?

While we are talking neuro- How favorably do anesthesia schools look on neuro ICU experience? Any SRNA's or CRNA's around here that have worked neuro before school? Did you feel like it prepared you well for school and future practice?

Thanks for any thoughts... -Lorus

[DustinRN]

Are you sure the diastolic pressure goes down? I can't figure a reason for the diastolic pressure to go down. I see why the systolic goes up to reperfuse the brain from incr ICP, but I can't figure for the life of me why the diastolic goes down. Anyone know?

[FlyingED]

Per AACN's clinical reference for critical care nursing

"Blood pressure is mediated at a reflec level in the medulla. . . . The mechanism for this riad of symptoms appears to be ischemia and pressure upon medullary brain structures."

The book I am ref. is very old, but what I have on hand. It does not go into the physiology merely states the reason.

[stressednurse]

Hey Lorus,

Now you sparked my interest and I am not sure why the diastolic goes down. Racking my brain as I used to work neuro ICU.

Just a bit of personal info, 3 years out of ICU and just accepted a hospital job to work per diem in ICU and telemetry. I burned out and took a break in geriatrics but !!!!I am coming back to what I really love. I am looking forward to having patients with at least 5 lines coming out of their bodies so I can see whats going on.

:)

[keermie]

This is not an answer out of a book, but the way that I would explain the low diastolic: the increased systolic is a result of increasing inotropic contraction of the heart to increase pressure thus also increasing pvr (like aortic regurg). The decreased diastolic is a result of shifting the diastolic pressure-volume curve right by increasing left ventricular volume and/or elasticity. Another component to this triad is bradycardia as well, which further potentiates the formentioned physio.