Ch 17 evaluating Electronic Fetal Monitoring Strips


Evaluating Electronic Fetal Monitoring Strips
Chapter 17 This is a fetal monitor strip and this picture
is taken from your book Feg 17.6. The top portion shows the fetal heart rate
and the bottom shows the uterine contractions. Normal fetal heart rate is 110-160 bpm per
your textbook. There are a few other sources that have slightly
different numbers but for testing purposes, we will follow your book at 110-160 bpm. Anything less than 110 is considered bradycardia
and anything over 160 is considered tachycardia. To determine the baseline you look at a 10
minute period. When you look at the strip on the screen,
we are looking at the top portion of the strip. Each little box is 10 seconds and there are
bold lines every 1 minute. So the strip on the screen is over a 12 minute
period. You are determining what the average heart
rate is measured over a clear 2 minutes in a 10 minute window. It is hard to read this one on the screen
so looking at this in your book will be easier. When determining the baseline it has to be
rounded to the nearest 5. For example, you can’t say the baseline
is 132. It has to be 130 or 135. You can not accurately detect anything between
the 5’s. The baseline in this one is 135 bpm. Please don’t get frustrated if you can’t
see that. We will practice more in class as well. I am going to use this same strip to talk
about variability. This term describes the fluctuations in the
baseline FHR that cause the printed line to have an irregular wave like appearance. This is one of the hardest terms for students
and new nurses to understand. It is that fluctuation. So you are the labor nurse and you are in
your patients room. You are looking at the monitor which will
flash the FHR and put it on the paper. So you are watching the monitor and it reads
135, then the next beat it is 138 and then 132 and 135, 134, etc. This fluctuation is that variability. There are terms for how much variability we
are noticing. First is absent variability. This is where there is no fluctuation. The FHR is consistently 135 and never changes. That shows up as a flat line. What do we know about the heart and a flat
line? It is not good. This baby is compromised and not tolerating
labor at all. The next term is minimal variability. This is a fluctuation of 5 or less beats. Fig 17.7 A shows that minimal variability. The baseline in that strip is 150 and you
can see it barely veers away from 150. This baby could be sleeping, mom could have
received some pain meds or baby could be compromised as well. Your books also lists other things that can
affect the variability. As the nurse, we need that background info. Did we just give mom some pain meds? If so, we are anticipating this could happen. Changing maternal position can sometimes help
the variability to increase. Also providing mom with something cold to
drink and with some sugar (juice) can wake up the fetus. Short spurts of minimal variability are good
but we don’t want this to go on the whole labor. Next is moderate variability. This is the fluctuation from 6-25 bpm and
is a good thing. This shows baby is tolerating labor well. Fig 17.7B shows moderate variability. You can tell with each beat that it is moving
more. Remember when you are accessing variability
you are looking a clear 2 minute strip over 10 minutes. The last type of variability is called marked
and that is where it is over 25 bpm fluctuations. Your book doesn’t have a picture but I will
see if I can find one to bring to class. Accelerations are a good thing and another
thing we want to note on our monitor strip. An accelerations indicates fetal well-being. Since we can’t see inside the uterus to
be sure baby is doing well, having accelerations present on the monitor strip is the next best
thing. An acceleration is 15 beats above the baseline
for at least 15 seconds. Remember 15 by 15 and they are good. This is Fig 17.8 from our book. You first have to determine the baseline. In this strip it is 135. So that means in order to be an acceleration
it has to be up to 150 bpm for at least 15 seconds and both of those accelerations on
this strip does that. When determining the 15 seconds, look at the
opening of the acceleration. Remember each of those small boxes are 10
seconds. We talked about non stress tests last week
and one of the criteria for a reassuring non stress test is to have two accelerations in
a 20 minute window. It show the fetal has adequate oxygenation. If the fetus is less than 32 weeks, they only
need to have increase from the baseline of 10 bpm lasting a minimum of 10 seconds. This is due to the fact that CNS is not fully
developed yet. Accelerations that last more than 10 minutes
are considered to be a change in the baseline and not an acceleration. Accelerations are good so the nursing interventions
include just documenting. Decelerations are something else we evaluate
on the EFM. This time it will be a decrease from the baseline
and may indicate baby is compromised. We will talk about each of these individually. The 3 things you need to remember about decelerations
are 1. Are they good or bad? 2. What causes them? 3. What are the nursing interventions
This is a picture of early decelerations. If we ask ourselves the 3 questions: 1. Are they good or bad? They are good. 2. What causes them? Head compression. The fetal head is getting smooched a little
bit with each contraction and that is what is causing the causing the deceleration. 3. What do we have to do about it? Nothing but document. Since they are a good thing and they do not
indicate fetal compromise, we just have to document our findings in the EMR. Now to identify early decelerations, you will
notice on the monitor strip that you see the dip from the baseline and that is the deceleration. Early decelerations will mirror the contractions. The contractions are on the bottom portion
of the monitor strip so if you were to flip the early decels over, they would look just
like the contractions. They basically start the deceleration process
as the contraction starts and once the contraction is done, so is the deceleration. The FHR is back to baseline. With each contraction, the head gets smooched
as it is trying to move down the birth canal and once the contraction is over, it is not
getting smooched anymore. Remember earlies are good. It is always good to be early (to class, clinical). Late decelerations are a bad thing. It indicated uteroplacental insufficiency. This basically means insufficient gas exchange
is occuring so the fetus is not receiving what it needs. We ask our 3 questions. 1. Are they good or bad? Bad. 2. What is causing it? Uteroplacental insufficiency-poor gas exchange. 3. What do we do about them? There are nursing interventions we must do. The first one is to change the maternal position. Left side is best but if she is laying on
her left side, switch her to her right side. Sometimes just changing position will be enough
to get that gas exchange going again. The next thing we do is if she is receiving
Oxytocin (pitocin) during labor, turn it off. Remember, Oxytocin will cause contractions
and with each contraction, the fetus is already receiving less oxygenation so we don’t want
her to keep contracting and causing more fetal compromise. The next thing we do is to give mom an IV
fluid bolus. This extra fluid will help with the blood
volume to help move blood volume to the placenta. You also will put oxygen on mom at 10L via
face mask. You will contact the provider and if these
late decelerations continue, you will prepare for delivery. The way we identify late decelerations is
that they typically start after the contraction has already started. Typically it is after the nadir or peak of
the contraction before they start. And they do not return back to the baseline
until after the contraction is over. If you look at that strip and you look to
see when the contraction is over, the FHR is still dipped down low. They usually do not dip below 40 bpm below
the baseline. Remember, lates are bad. It is never good to be late to class or clinical. Variable decelerations are caused from cord
compression. This can be the umbilical cord around the
neck, body, a knot tied in the cord or the fetus lying on the cord. You ask yourself the three questions. 1. Are they good or bad? Bad. What causes them: umbilical cord compression
and 3. What do we do about them? Your interventions are going to be close to
the same as what you would do for late decelerations. You change maternal position. If the fetus is laying on the cord, this can
help alleviate that. They will sometimes put mom on her hands and
knees as well. This once again will take the pressure off
from the cord. Another position is they will have her get
in the prone position, lean on her arms and she elevate her hip and buttocks in the air. Having them higher, will take the pressure
off the cord as well. You would consider turning off the pitocin
is she was on it. It is not a definite to turn it off .You have
to see if she is just having one or two variables or are they all the time? Is there still good variability and are there
accelerations? If so, they may keep the oxytocin going. They can give in IV bolus of non-medicated
fluids they have running. They will put oxygen on at 10L via mask and
they will contact the provider. Remember in the last podcast I talked about
an amnioinfusion? This would be a time they would consider that
.The fluid they put in the uterine cavity could cause the head to move off from the
cord if that was the problem. When looking at the EFM, variable decels are
either V or W in shape. Remember V for Variable. They are abrupt down and abrupt back up. This is usually less than 30 seconds in duration. This can happen with a contraction or they
can appear without regards to contractions.

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