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Can anyone explain the exact mechanism by which this happens? Is it just the Fentanyl?
Hello, RaeT, RN,
Try this link:
My extremely basic ( :doh: ) grasp on this is that the epidural can block sympathetic nerves that are related to blood pressure control.
An internet search will probably tell you more than you EVER wanted to know on the physiology behind what is going on with this, and the resulting vasodilation/hypovolemia/hypotension.
Can anyone explain the exact mechanism by which this happens? Is it just the Fentanyl?
http://www.healing-arts.org/mehl-madrona/mmepidural.htm . check out this website, it explains everything you need to know. I am a labor and delivery nurse and have been for several years and one of the best resolutions for decreasing hypotensive episodes is to hydrate your pt with at least a 1000ml to 1500ml of LR or NS as a bolus prior to epiddural placement and do not keep your pt flat on her back for long periods of time, this is where the vagal response happens. Instead put a small roll under one of her hips so the pt is slightly tilted. Follow these 2 steps and you should be ok.:)
My extremely basic ( :doh: ) grasp on this is that the epidural can block sympathetic nerves that are related to blood pressure control.An internet search will probably tell you more than you EVER wanted to know on the physiology behind what is going on with this, and the resulting vasodilation/hypovolemia/hypotension.
This is it, in a nutshell. It's so common, you should plan for it, and if possible, have your MD/anesthetist draw up a premixed syringe of ephedrine, labeled and marked for you, to give in the case you need it emergently, to bring that blood pressure back up. Ours do this, and it's saved my bacon on more than one occasion.
We usually use anywhere from 5-10 mg Ephedrine, drawn up in a TB syringe, prepared by the MD, if needed.
deb
PS: be careful in pre-epidural hydration, particularly if a patient is on Pitocin (which acts like anti-diuretic hormone). Some studies are suggesting pre-load of NS or LR of 500ml-to 1000ml MAX is all you need to offset the possiblity of hypotension in patients. Too much fluid volume overload is at least as bad as too little. Keep careful I/O on all patients on IV fluids in labor. Watch your balances. Pulmonary edema, while rare, is something I have seen in women over-hydrated in labor and immediately after. Even in healthy women, you have to be careful.
Know where the ephedrine is, and how to use it, if you don't already, or make sure you have an Anesthetist immediately available, to handle this, as needed.
deb
RaeT,RN
167 Posts
Can anyone explain the exact mechanism by which this happens? Is it just the Fentanyl?