Physiology of FHR monitoring

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I am semi-new to L&D. I have been to numerous monitoring classes and remember hearing somewhere there could be a tracing yet the heart could not be mechanically functioning. This had to do with beat to beat variability, or rather, the loss of it. Similar to an adult in PEA. But, we would not know it until the birth obviously. This discussion came up after a stillbirth of a baby that had a FHR tracing up until birth although it was absent variability for quite a while. The other nurses couldn't understand how it could have had a tracing, yet be born lifeless. Am I totally off here or have others heard this????? I have no clue where or when I heard it and can find nothing as I research it. I find when I "google" these types of things, the only info that comes up is for lay people. Would appreciate any info on this so I can share it with my coworkers or admit defeat;)

I am semi-new to L&D. I have been to numerous monitoring classes and remember hearing somewhere there could be a tracing yet the heart could not be mechanically functioning. This had to do with beat to beat variability, or rather, the loss of it. Similar to an adult in PEA. But, we would not know it until the birth obviously. This discussion came up after a stillbirth of a baby that had a FHR tracing up until birth although it was absent variability for quite a while. The other nurses couldn't understand how it could have had a tracing, yet be born lifeless. Am I totally off here or have others heard this????? I have no clue where or when I heard it and can find nothing as I research it. I find when I "google" these types of things, the only info that comes up is for lay people. Would appreciate any info on this so I can share it with my coworkers or admit defeat;)

Thank you butterball1980 for bringing up this question. I happened to have the same question as yours. When I read some books, I did see tracing of fetal heart rate, whereas the book ended up saying it was a still birth. I was curious too. How can I identify if the fetus is still alive or dead if I can still see FHR 140? Just absent variability? I'll really appreciate it if you can find the answer and update us.

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I have sent some letters out to the local educators that do our fetal monitoring courses and hoping for some responses soon. If I don't hear back from them, I'll send off some questions to some of the Level 3 hospitals. I really can't believe it's so hard to find information about this! It has become a really interesting subject for me though, so hopefully will hear something soon. I'll post as soon as I do!

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This is very interesting! I know for sure that when I put on an EFM or ISE I palpate the maternal radial pulse and chart that (AWHONN guidelines) everytime...even during decels. Moms with IUFD's may have a HR elevated to mimick a FHR d/t infection. OMG...that amost felt like I was back in nursing school when I just wrote d/t infection!!!! Anyway, that would be interesting to know if that was in fact not maternal and fetal PEA if possible.

:)

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Specializes in Specializes in L/D, newborn, GYN, LTC, Dialysis.

If in doubt, I put on a pulse ox to compare fetal heart rate to maternal pulse, picking up both and tracings on the FHM for the records and charting.

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Specializes in Cardiac.

Good point. Using a oulse ox or palpating meternal Hr and DOCUMENT! I'll remember that.

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Specializes in Nurse Leader specializing in Labor & Delivery.
If in doubt, I put on a pulse ox to compare fetal heart rate to maternal pulse, picking up both and tracings on the FHM for the records and charting.

I had a very interesting case yesterday, wherein the mother was tachy, in the 130s-140s, and at many times I could not differentiate between MHR and FHR. Applying an FSE was not possible, due to being intact.

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Specializes in Specializes in L/D, newborn, GYN, LTC, Dialysis.

Time for real time U/S then if this were to persist, eh?

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Defenitely time for US at that point. I had a mom come in recently @ 21 weeks and thought she was SROM. I tried to apply US and nothing so I used doppler and I got a HR of 120 but immediately I palpated maternal radial pulse (habit) and it was hers! She was so nervous that she got herself all worked up. I had a feeling too since I would expect a 21 weeker to be in 150's or so. She told me she had an anterior placenta. Once the doc US'd we saw the fetal heartbeat right away in 150's! The RN's who trained me told me they did have a pt with IUFD who was tachy and looked like the fetal tracing was normal. Ever since I heard that I ALWAYS manually palpate a maternal pulse and document when I apply a monitor.

For example: EFM applied. FHR audible @ 135 bpm. Maternal radial pulse palpated @ 80 bpm.

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