Published Nov 1, 2014
Bluebell.
83 Posts
Why is nitroprusside contraindicated in patients with aortic coarctation with compensatory hypertension?
Here are my thoughts-- Because the aortic coarcation itself does not allow adequate perfusion to the rest of the body, the compensatory hypertension helps to push as much blood to the tissues as possible, so that the tissues/organs will get adequate perfusion. I'm guessing the reason is because nitroprusside (as an anti-hypertensive medication) will reduce the compensatory mechanism, causing decreased perfusion to the body's tissues. Is this correct?
I have a presentation on this drug and I want to be able to accurately explain this to the class. My textbook does not explain why, and internet sources are not helping.
Anyone's help would be most appreciated :)
RunBabyRN
3,677 Posts
I haven't seen evidence on why it's contraindicated, but when I saw your question, the reason you listed is the same one I came up with- it would counteract that compensatory mechanism, and they could have a dangerously low BP. Perfusion to the vital organs is the biggest factor.
EricJRN, MSN, RN
1 Article; 6,683 Posts
Usually in coarc you have a gradient (big difference) between the pressure/perfusion of the upper body versus that of the lower body. The pressure is high in the arms, but low in the legs. Our neonates with it will often have absent femoral pulses.
We usually don't treat high BP in neonates (which is usually detected in the arms) who have coarctation, because it can further decrease the perfusion to the lower body and make the baby even more acidotic and sick. The exception is hypertension that occurs after the coarc repair; I think many places still use nitroprusside for that.
Esme12, ASN, BSN, RN
20,908 Posts
Your thouhgts are correct.
Thanks everyone for your help!
@EricJun- So would it have the same effect on adults as the neonates (decreased perfusion to the lower body)? You also mentioned that there is an increase in the BP above the body, so that probably includes the brain too. I am guessing you would want to keep that BP a little higher, if someone were to have decreased cerebral perfusion.
The bottom line here is that you must maintain perfusion to the vital organs however that is possible. Before correction of this anomaly the body finds it necessary to maintain hypertension to maintain perfusion....if the B/P drops perfusion decreases of ceases to exist.
Esme12,
Thank you for your clarification. It was most helpful.