Bradycardia during birth

[FancyD]

I'm trying to phrase this clearly...

How long is too long for bradiacardia, during labour? How long would you wait before knowing that something was wrong? I've tried to google this, but can't find what I'm looking for. I guess I want to know what the standard of care is WRT this kind of distress.

TIA!

[Malga]

It depends on the whole picture and how low the bradycardia is and how close the birth is.

This info is from my Evidence-Based Practice perinatal book (2008):

Baseline bradycardia is a FHR of <110 beats per min for at least 10 min. This may be caused by hypoxemia (lack of oxygen) or bradycardia may cause hypoxemia. The depth, duration, and presence of variablity are critical components in making clinical decisions.

A sudden profound bradycardia is a medical emergency. Sometimes called terminal bradycardia-- outcome again depends on how long the baby has already been struggling and how fast you can get the baby out.

If FHR is between 80-100 and variability is good, the baby will tolerate for some time (not exactly sure how long).

[MsBlack]

As I understand it, it also depends on WHEN it happens in labor--can be totally normal during second stage (within limits, of course--80--110 or so).

[FancyD]

So, what about 6 hours of bradycardia? Does it still depend on how low the heart rate is?

[Jane]

In what situation? Are we talking during pregnancy? Early Labor? Good labor at 6 cm? During pushing?
At home?
At the hospital?
At a fancy hospital with 4 ORs?

I don't think there is a definite answer b/c there are so many variables.
For example, a baby might have a heartrate of 100, the mother is in the hospital, on monitors, baby shows good variability, blood gases and pH are good, and she is a second time mom, pushing well, baby likely to be born within 20 minutes.
The extreme other example is a baby with a heartrate of 100, no variability, the mother's a first timer, not in labor, 0 cervical dilation.

[mwherbs]

not going to play around with much for long except pushing- what is the heart rate with scalp stimulation good accelerations then it is probably still fine and I will wait during pushing- if position changes in a laboring mom do not make a difference -- I am most likely going to talk to mom and dad- and we will be going to the hospital
do we have ROM for how long, mec, abnormal labor pattern, post dates, GBS status,mom's pulse rate.... how far from a good hospital that has a nursery ? do the ambulances have paramedics or just EMTs?

hospitals may have a different tolerance and studies with a medicated population are going to be different than our unmedicated population -- I have seen hospital ignore a baseline of 100 with what I think of as poor variability - because they see that enough in their medicated moms/babies-, when a mom isn't medicated they are so use to the other numbers they don't change their evaluation -when the baseline moved to 80 in pushing mom had oxygen on her face- this mom had poor contraction pattern was on pit but no other meds- this particular baby was fine but interestingly newborn screening for hypothyroid came up and ultimately DX'd with hypothyroid -


normal baseline heart tones are 120-160 --- I am not staying home for 3 hrs with a baseline heart rate that has shifted from a prenatal rate of 140 to a labor baseline of 100 and we transfer and she has a vaginal birth fine and well -- they have the skills and the staff to handle poor outcomes- if you have a labor baseline of 110-100 with dips to say 80's- 50's ( you know a heart rate you are checking against a mom's pulse to be sure you have the right thing) and then you know pushing can even lower the rate- why try to stay home what are you trying to achieve ?

if you think of it this way- a baby with a heart rate below 100 if she/he were out we would be bagging (resuscitation) we don't have 3 -4 hrs worth of oxygen to put oxygen on mom --

[FancyD]

Thanks for the answers. There are just too many variables to get an answer. Again, thanks for all your information!