difference between neurogenic shock and autonomic dysreflexia

[cyndiangel13]

Hi. I am attempting to figure out the differences in neurogenic shock compared to autonomic dysreflexia.

What I know:

neuro shock coincides c spinal shock. Signs/symptoms are hypotension, peripheral vasodilation, venous pooling, no perspiration below level of injury, fever and decreased cardiac output.

It is caused by loss of ANS innervation below level of injury.

AD s/s include HTN, bradycardia, diaphoresis, pounding HA (d/t HTN)

it is caused by stimulation from urinary retention, bowel impaction/constipation and/or skin irritation (sitting in one spot too long, sunburn, ingrown toenail, etc)

It can happen long after the spinal cord injury after spinal shock has resolved.

My question is...aside from knowing the s/s of each, why does AD happen...what is the main difference?

everbody? anybody? please help...thanks so much!!!

[EricJRN, MSN, RN]

I think you've already hit on the biggest difference I can think of: timing. While autonomic dysreflexia remains a concern for months or years after an SCI, a patient would enter neurogenic shock a short time after the injury.

[Daytonite, BSN, RN]

autonomic dysreflexia and autonomic hyperreflexia are interchangeable terms. it occurs after resolution of spinal shock and in patients with spinal cord injury at or above t6 and is an emergency. according to my mccance and heuther (pathophysiology: the biologic basis for disease in adults and children) something causes the autonomic nervous system to be stimulated and is accompanied by a paroxysmal increase in blood pressure--that rise in blood pressure which causes a "massive uncompensated cardiovascular response to stimulation of the sympathetic nervous system" (mccance and heuther's words)--is a key element of the dysreflexia. they are saying that the systolic b/p can go as high as 300 mmhg. what happens next is that baroreceptors (pressure receptors) in the blood vessels of the brain, carotid sinus and aorta will normally sense this elevated blood pressure and signal the parasympathetic system to dilate the vessels to accommodate the elevated blood pressure. however, here's the problem: efferent impulses are unable to pass through the cord at the point of original injury, so the visceral and peripheral vessels below the level of the spinal injury can't get the message. the consequence is that the blood vessels below the level of injury cannot respond to the hypertension. thus, your severe pounding headache and other cardiovascular symptoms.

[cyndiangel13]

thank you thank you thank you Daytonite!!! That brought it ALL home for me!!! Just in time for the final tomorrow!!! heehee...it also helped to enhance my critical thinking!!! again, thank you soooooo much!!! Answered my question completely!!! Did i say thank you? Thank you!!!

[Daytonite, BSN, RN]

Good luck!

[cyndiangel13]

just wanted to let you know I passed my final and i'm going to 4th level!!!!!! Last level for me:) yayyyy!!!! thanks again!!!

[Daytonite, BSN, RN]

That's wonderful.

[flightnurse2b, LPN]

daytonite, i want you as a instructor, seriously. i learn so much from you.