Uterine atony

[putmetosleep]

How does administering pitocin immediately after the baby is removed during a C-section really prevent uterine atony if there is neuromuscular blockade on board? Doesn't the NMBA in itself produce uterine atony?

Thanks so much.

[Angel@MyTable, RN]

Just as a student I can tell you that pitocin causes uterine contractions, which I would think would help prevent uterine atony.

[RedCell]

How does administering pitocin immediately after the baby is removed during a C-section really prevent uterine atony if there is neuromuscular blockade on board? Doesn't the NMBA in itself produce uterine atony?

Thanks so much.

Hey man, what kind of muscle is the uterus made up of? Second, what type of muscle do nondepolarizing and depolarizing NMBAs have an effect on. Hint...not smooth muscle (not to any clinical significance).

[wtbcrna, MSN, DNP, CRNA]

How does administering pitocin immediately after the baby is removed during a C-section really prevent uterine atony if there is neuromuscular blockade on board? Doesn't the NMBA in itself produce uterine atony?

Thanks so much.

The medications work on different receptors. NDMBs work on nACh receptors at the neuromuscular junction and the pitocin works on the oxytocin receptors in the uterus.

[CRNA, DNSc]

NMBlockade occurs at the neuromuscular junction- the uterus is composed of smooth muscle which is quite different than skeletal muscle, NMBlockers do not affect smooth muscle the same way - think about it- if NMBlockers relaxed smooth muscle we would be using it to stop severe asthmatic attacks or prevent premature uterine contractions!!:)

[deege58]

How does administering pitocin immediately after the baby is removed during a C-section really prevent uterine atony if there is neuromuscular blockade on board? Doesn't the NMBA in itself produce uterine atony?

Thanks so much.

First i have to say that i love your user name!

You bring up something that in about 20 years of ob, i have never given any thought to. I have never seen any problems with atony during a c/s, not to say it doesn't happen, i just havent encountered it. But when they are suturing they have the uterus in their hands and can massage it as well. I'll have to do a search now to see what i can find. I'll be interested to see what others post in reply. Good question though.

[nurselizk]

Not only will it not block smooth muscle, it won't cross the placenta.

[putmetosleep]

NMBlockade occurs at the neuromuscular junction- the uterus is composed of smooth muscle which is quite different than skeletal muscle, NMBlockers do not affect smooth muscle the same way - think about it- if NMBlockers relaxed smooth muscle we would be using it to stop severe asthmatic attacks or prevent premature uterine contractions!!:)

Duh. Haha sometimes the most obvious answers are the hardest ones to come up with. I didn't even think about smooth vs skeletal muscle. Thanks for clearing that up for me! Can you tell that my brain is in a state of overload or what?!

[Qwiigley, BSN, MSN, DNP, RN, CRNA]

Good questions, though. Many people can learn from questions like this, especially students. Ask away. There are so many CRNAs who are very experienced on this site.

Remember, there are no stupid questions when people's lives are at risk.