Friday, July 31, 2015

Fetal Heart Monitoring ( Why do we do it? What does it tell us?)

Hello again! I've once again been a huge slacker at writing, but will try to be better:) I recently had a case (a few months ago) of a patient who was very self educated so to speak in the ways of childbirth. She had her typical birth plan and desire to go "natural." Now, first off, let me say, I fully support natural and birth plans, and such to the extent that they are safe, and that if I detect something may not be going well with your baby from monitoring and such that my patients are going to trust me and my formal education and experience to know when more monitoring or intervention is necessary.


However, in this scenario, many natural patients desire intermittent monitoring which is acceptable when the baby has a reactive initial non-stress test for 30 minutes of monitoring and is not having decelerations in the heart rate during or after contractions. If neither of the those criteria are met, further continuous monitoring is necessary.


I would like to state the reason why this issue has become complicated for some "natural" patients. Since the 1970's, when continuous fetal monitoring came to be the standard of care, there has been no decline in the rate of cerebral palsy cases in newborns. There has also been a rise in cesarean deliveries, likely because we panic too much over certain types of decelerations in the heart beat and rush to c/section too soon. Thus, increasing cesarean rates. The cerebral palsy rate situation is complicated. We know preterm birth causes many of the these cases, and since the 1970's we have gotten more aggressive at saving more and more babies at earlier gestational ages, even as early as 23 weeks, which obviously holds risk for  CP (cerebral palsy). Cerebral palsy, we know is caused from lack of oxygen at some point to an area of the brain. This could even occur in utero prior to birth and have nothing to do with preterm birth or even anything going wrong during the delivery. These are the confusing cases. So, with that knowledge, ACOG (American Congress of Obstetrician's and Gynecologists) has said, that it is appropriate to do intermittent monitoring in labor on low risk appropriate women and that not all decelerations in the fetus warrant urgent delivery. So.... for a non expert who sees their baby have a decel or two and not know how to accurately evaluate the whole picture, they may think, well, ACOG says I'm fine, my baby is moving, send me home and do nothing more.  How many of you feel good about that if that was your baby??


The problem with this logic is that it depends on the gestational age of the baby, the type of decels, if there are contractions, bleeding, etc.  If the patient was only 25 weeks along and the decels were just occasional variable type, meaning the baby is just rolling on the cord and dropping the heart beat here and there, that is a normal variant we expect to see. We would never deliver a 25 week baby early for something like that. However, let's say the patient is more than 1 week over due, so she is almost 42 weeks. We know that there is an increased risk for stillbirth in a patient like this. Let's now say her baby has some random "late" decels. This means the deceleration is occurring after a contraction. This is a concerning type of decel. This means the baby is experiencing a brief drop in oxygen as the baby's chemoreceptors trigger a response for the baby to try to constrict peripheral blood flow back to the baby's vital organs. This tells us the placenta is not functioning as well as it should. This is a baby that could be in jeopardy if it is not delivered in the near future. If the baby continues to have late decels, it will slowly become hypoxic and either die in utero if sent home this way or if not delivered vaginally in a reasonable time or by c/section could also experience lack of oxygen and be at risk for serious brain injury. We can assess how hypoxic a baby is at birth by obtaining a cord ph. If this is less than 7.0, we know the baby experienced some level of lack of oxygen. If it was rapidly corrected and delivered, those babies usually do fine. However, if the hypoxemia went on for a long period of time and was un- noticed those babies can be permanently damaged for life, meaning wheelchair, feeding tube, lack of communication, etc.


There are other ominous decelerations that we know result in bad outcomes as well. Prolonged minimal variability- meaning the fetal heart beat doesn't fluctuate more than 5 beats per minute. It pretty much looks like a straight line, there are no changes and no accelerations. This is also a sign of placental insufficiency and is not good. This is a baby that needs to be delivered. The other type of decel that is an emergency is a prolonged decel. If your baby's heart beat drops in labor and doesn't come back up despite interventions such as rolling you, increasing IV fluids, or meds to stop contractions, your baby needs an emergency c/section. Babies show us they are in trouble when their heart rate suddenly drops below 100 and doesn't come back up. They are not getting the oxygen they need and will die without delivery.


As far as ACOG goes, they would never support or stand by a provider who ignored a fetal tracing with ominous signs such as late decels or minimal variability, even if they were irregular and periods where the rest of the strip looked ok, such as was the case with my patient a few months ago. The risk in ignoring this, or sending someone home to potentially come back with a dead baby is too great a risk. I've thought a lot about this patient and her case over the past few months because of her difficult personality and trying to explain the importance to her of keeping her for monitoring and ultimately delivery for the safety of her baby. She did end up delivering a healthy baby by c/section a day later due to non-reassuring tracing and a large baby that wouldn't descend, but I have felt perplexed by her case due to things she said to me while she was mad about staying and the way she felt she was right over the rest of us who have seen things go awry quickly over the years if non-reassuring tracings on babies are not delivered.


I guess what I am saying here is, I see a LOT of natural patients, and I do a LOT of intermittent as well as continuous monitoring and non-stress tests in my office and the hospital on babies, and not every situation is the same, whether you are "natural" or not. And, if you are "natural," your placenta can still age and have problems that warrant intervention. And while most the time intermittent monitoring is appropriate and most decelerations are a normal variant during labor and don't need much intervention, if any, some are definitely NOT ok, and are clearly giving us warning signs such as a yellow or red light to slow down or stop and do not proceed or there may be a problem. These warnings must be heeded. Please be aware that you cannot read one or two articles, even from ACOG and believe you know how to read a tracing properly and self diagnose. Those of us in this profession have taken many classes and are certified in reading these tracings. We have years of experience in this. We ultimately have your baby's best interest and health in mind when we want to monitor more at certain times or if there are ominous signs.


Take Care out there ladies!!

3 comments:

victoria eden said...

I like your blog a lot. Its informative and full of information. Thank you for sharing.
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Ernie and Meg Guerrero said...

I enjoyed reading this. Monitoring will not take away from having a natural birth.

Ernie and Meg Guerrero said...

I enjoyed reading this. Monitoring will not take away from having a natural birth.