Enducing/Reducing Labor

[FL_Medic]

Has anyone seen or heard of the use of ADH, or fluid challenges on a pt. in labor?

[AZCEP]

Not unless they are septic.

[FL_Medic]

Here is a question.. if we gave vasopressin to a 3rd trimester pregnant pt. in a code situation as first line med. And we get a save, is labor something that we may have to worry about now? I know if it is there will be a good chance of a stillborn, but I was just wondering.

Or should we then give a good fluid challenge?

[Ridryder 911]

Okay .. hmm why?

I have used Pitocin, Brethine, Magnesium, etc..

R/r 911

[FL_Medic]

Okay .. hmm why?

I have used Pitocin, Brethine, Magnesium, etc..

R/r 911

Antidiuretic Hormone (ADH)

The function of ADH is to inhibit or prevent the formation of urine. Osmoreceptors monitor the solute concentrations in the blood. During pregnancy the osmoreceptors are "reset" to deal with the increased blood volume of pregnancy. If the osmoreceptors send excitatory messages to the "ADH secreting neurones," less urine is produced, leaving more volume in the circulating blood.

The actions of the hormones of the posterior pituitary are especially important to consider in the pregnant woman who is at risk for preterm labor. Maternal dehydration may trigger the secretion of ADH by the posterior pituitary. It is thought that oxytocin may also be released at the same time, bringing about uterine contraction before the optimum time. These uterine contractions, or uterine "irritability" (low intensity, high frequency contractions) of preterm labor are often treated with maternal hydration. Women at risk for preterm labor are encouraged to drink copious amounts of water throughout the day. And, if hospitalized for contractions, hydration with a bolus of IV fluid is often effective to "quiet" the uterus.

Secretion of ADH is also stimulated by pain, low blood pressure and drugs such as nicotine, morphine and barbiturates. In trauma situations, a great deal of ADH is released, to counteract blood loss. The result is constriction of smooth muscles of the blood vessels, in order to raise the arterial blood pressure. (As a result, of this "pressor" effect, ADH is sometimes referred to as vasopressin.) Very little blood is getting to the baby through the constricted blood vessels.

[AZCEP]

You sit in the station dreaming this stuff up, don't you? :?

Not exactly a situation that is likely to occur, but what the heck, I'll bite.

Vasopressin and Pitocin are both Pituitary hormones. When the signals to release one occur, in large enough volumes, the other can be released as well. As endogenous hormones this may be a factor to consider. As exogenous administrated medications, the chances are greatly reduced.

One factor would be the Vasopressin's half-life, and the amount of time that it took to accomplish a ROSC. Another would be the fact that when hormones are introduced from outside the body, the healthy gland will limit the release of anymore of the involved hormone. The negative feedback mechanism accomplishes this.

Possible? Sure. Probable? No. You would probably need to administer an inordinately large amount, shortly before ROSC to get the response you describe.

[Ridryder 911]

Yes, I was quite aware of the physiologic response of ADH, but did not see the implication or the consideration of such in an emergent situation. You discussed volume decreasing uterine contractions, this is true , however in a normal homeostatic environment. Remember ADH is responsible for the release of Angiotension II when baroreceptors are enacted, in shock syndromes. Sympathetic overdrive usually occurs, causing more conservation measures. Fetal distress can occur immediately.

I was confused by the implications of needing the response of such in cardiac arrest versus traumatic injuries. Regardless, physiologically both would have the same outcome. One, should remember the key treatment and emphasis should be on resuscitation of the mother, and maintaining fetal circulation. A dead mother is not going produce an active labor nor a viable child. Resuscitation of the mother so possibly an emergency C-section, if warranted (>30 weeks, gestation) must be performed rapidly and is very controversial. There are many dependent factors that one has to consider and this is definitely not a pre-hospital decision. Again, resuscitation of the mother is our primary goal.

Let's not forget seeing the forest without seeing the trees first.

R/r 911

[FL_Medic]

Ok, yea I am sitting in the station dreaming this stuff up, lol. I was just wondering, not trying to teach, trying to learn.

Thanks for your input.

[AZCEP]

Students teach things all the time.

See the "Things you didn't know until you had kids" thread for proof.

It is a reasonable question based on the pathophysiology, but it looks like you stopped a bit short in thinking it through. No problem there. The willingness to ask the question is the most important thing you need to have. Otherwise, you tend to think you are always right, in how you are thinking.

I just don't believe I've ever seen anyone with similar questions.

Very impressive for a new provider.

[FL_Medic]

Students teach things all the time.

See the "Things you didn't know until you had kids" thread for proof.

It is a reasonable question based on the pathophysiology, but it looks like you stopped a bit short in thinking it through. No problem there. The willingness to ask the question is the most important thing you need to have. Otherwise, you tend to think you are always right, in how you are thinking.

I just don't believe I've ever seen anyone with similar questions.

Very impressive for a new provider.

Thanks again