Speaker 1: All right, so in today's podcast, we're going to be
going over a couple high old complications related to pregnancy.
This is going to be the first of a few
podcasts I plan on making on pregnancy related complications. Thank
you everybody for the support, the really nice comments, the
five star reviews on Apple Podcasts and Spotify. I truly
do appreciate it. Thank you so much. And let's go
ahead and get started. So let's start with placental abruption
aka abruptio plucente. What is this, Well, it's a partial
or complete separation of the placenta at or after twenty
weeks of gestation. So we have this premature separation of
the placenta from the uterus. We'll talk about why this
happens in a moment, but first let's talk about timing.
So why is timing so important? Why is it generally
only considered a placental abruption if it occurs after twenty weeks. Well,
if this happens prior to twenty weeks, in that case,
it's usually considered to be part of a spontaneous abortion
rather than an abruption, except for some rare cases, and
then it also has to be prior to fetal expulsion,
and this part is pretty obvious. After the fetus is delivered,
the placenta naturally separates from the world the uterus, and
so this is no longer an abnormal finding. So again
timing it's after twenty weeks and prior to delivery of
the fetus. All right, So we have this placental abruption,
this separation of the placenta. Why is this happening, Well,
it's due to a rupture of maternal vessels in something
called the decidua basalus. So this is the main area
to focus on for patho thrumb and also plays a
role with the clinical consequences seen contractions, tissue brick down,
et cetera. But rupture of the maternal vessels in the
decidua basalus is what you need to know so quick
anatomy review. The placenta is where the nutrient and gas
exchange occurs between the mother and the fetus. It has
two sides, the baby side called the coreon and the
mother's side the decidua basalice, which is attached to the
uterine wall. The deciduo basalus contains the maternal blood vessels,
arteries and veins that supply oxygen rich blood to the fetus.
In a placental abruption, the vessels in the deciduoa basalus
mom's side become damaged or weakened, which causes them to rupture,
which obviously leads to significant bleeding causing hematoma. And all
of this just pushes the uterine wall in placenta apart
and the separation it can be partial or complete, depending
on the severity of the bleed. So basically to recap
in a placental abruption, vessels in the decidu of basalus rupture.
These ruptured vessels bleed and accumulate, which eventually causes the
placenta to separate and peel away. So then the next
question becomes why did these vessels rupture in the first place,
And that takes us to our risk factors. So think,
what are some things that damage and weaken blood vessels
that disrupt vascular integrity. Let's start with an easy one,
and that is smoking. So this is one of the
few modifiable risk factors. It's also associated with a fourfold
increased risk and it's thought to be related to its
phasoconstrictive effects which cause placental hypoperfusion necrosis et cetera. Another
one is cocaine again vasoconstriction, eschemia, et cetera. Up to
ten percent of pregnant women using cocaine to the third
trimester will develop an abruption hypertension. This one's really important,
five fold increased risk compared to normal intensive Obviously, anytime
the blood pressure is increased, you can have arterial wall damage.
And then the next one is trauma, so blunt trauma,
a motor vehicle accident, fall, et cetera. Even though this
isn't the most common risk factor, it's definitely popular on
exam questions and I have this one in school. So
in trauma like a motor vehicle accident, for instance, you
have this rapid acceleration deceleration of the uterus where the
uterine wall stretches with the sudden movement. As the uterus
is pretty flexible, but the placenta it's not so stretchy,
so it stays in place. So you have this shearing
force that just rips the two apart. And then we
have our last risk factor, which is previous abruption. Like
so many things in medicine, if you had it before,
good chance you'll hap it again. And in the case
of a placental abruption, very good chance. So there are
some other risk factors, but those are the five to
focus on, smoking, cocaine, hypertension, trauma, and previous abruption. All right,
let's talk about something super high yield next, and that
is your clinical manifestations. So for clinical manifestations, there's really
two things that you need to know, pain and bleeding.
Neither as one hundred percent in real life, but in
preparation for an exam, you need to assume you'll be
given the most common clinical presentation, which is abrupt onset
of vaginal bleeding and mild to moderate abdominal pain. So
let's talk about that vaginal bleeding. This is usually going
to be abrupted onset, and this is a key component,
but it's not very specific because there's obviously other causes
of third trimester bleeding, like with placenta previa, which will
go over next, and there is something called a concealed
abruption where most of the blood is actually trapped behind
the placenta, and in these cases, even in a very
severe abruption, there may be little to no vaginal bleeding.
So that's clinical knowledge, but for an exam, always be
thinking classic presentation, which is abrupt onset of vaginal bleeding,
as this will be how the vast majority of patients
present around eighty percent of individuals with a placental abruption. Next,
abdominal pain, so pain. This is associated with the uterine contractions,
which are often high frequency in low amplitude, So the
abdominal pain. It's important because on an exam, in some cases,
the only thing to differentiate an abruption from placenta previa
is the mention of some type of abdominal pain. So
classic presentation mild to moderate abdominal pain is going to
be typical. Back pain is also a possibility when the
placenta is on the posterior wall of the uterus. In
some cases the abdominal pain can be very severe, so
abdominal pain very important to remember. So clinical manifestations. Nothing's
one hundred percent in medicine, but for the exam, associate
placental abruption with painful vaginal bleeding at or after twenty
weeks gestation. Next is our physical exam, so really just
one thing to focus on, and this is really important
because it's another key to help you on your exam question,
and that is the uterus it's going to be tender
and rigid. On exam. You also may hear it being
described as hypertonic, which just means high muscle tone, which
is from those frequent contractions. So really important to remember rigid,
tender or hypertonic uterus. Okay, diagnosis next, So in acute
placental abruption, it's mainly a clinical diagnosis and you should
suspect this in any pregnant patient that has abrupt onset
of vaginal blas, abdominal pain contractions, especially in the presence
of uterine tenderness and increase uterintone. As we talked about before,
there are some other things that help support the diagnosis
feudal heart rate, abnormalities, disseminated intravascular coagulation which can be
associated with abruption. So remember again this is mainly a
clinical diagnosis and you should suspect it in any pregnant
patient with sudden onset vaginal bleeding, abdominal pain, contractions, tender
and rigid uterus. With that being said, you should also
know ultrasound can be helpful and what you should know
for your ultrasound finding is something that's known as a
retro placental hematoma. So a clot behind the placenta. If
this is present, this strongly supports the diagnosis and on
an exam question, if you see this mentioned, slam dunk,
it's a placental abruption. In real life it can be
absent and a good deal of patience, So it's great
if it's present, but not so helpful when it's not.
Ultrasound is also helpful to rule out your differentials such
as placenta previa, which will go over next. So again,
diagnosis mainly clinical, but the ultrasound what you're looking for.
The classic finding is going to be a retro placental hematoma,
all right, So treatment it depends on a lot of factors,
including hemodynamic stability of the mother, the status of the fetus,
and I don't think the questions you'll get will be
about treatment, but just so you have an idea. Part
of the treatment is focused on hemodynamic support for the mother,
so things like blood transfusion, IV fluids, et cetera. Of
course continuous fetal heart rate monitoring, and then depending on
a number of factors, often emergent delivery is indicated, whether
by vaginal or cesarean birth. Okay, so quick recap placental abruption.
Placenta is peeling away from the uterus prematurely. This is
at or after twenty weeks of gestation and prior to birth.
Those maternal vessels, whether diseased from hypertension, smoking, or damaged
from car accident fall, have ruptured and are filling that
separated space with blood. Most often will see bleeding on
physical exam. In some cases the bleeding can be hidden.
One thing I want you to remember is this patient
will likely be in pain, very likely contractions, et cetera.
Uterus is going to be tender and rigid. Diagnosis is
made clinically ultrasound. If it shows a retro placental hematoma,
slam dunk, But it doesn't always For things you need
to remember that always come up in the description on
an exam question. That's pain, bleeding, the rigid uterus, and contractions.
This is how I remembered it and hopefully it will
help you too. Instead of placental abruption, I used to
remember it as placental crab eruption. Think of a crab
with its little claws literally snipping the placenta away from
the uterine wall and crab and placental crab eruption stands
for four super important things you need to remember that
will be on an exam question. So C and crab
is for contractions, R is for rigid, as in a
rigid or hypertonic uterus, A is for abdominal pain, which
is so important, and then B is for bleeding. So again,
placental crab eruption, crab contractions, rigid, abdominal pain, bleeding. All right,
let's talk about the next condition which will be very
similar in many ways to placental abruption, and that is
going to be placenta previa. And this is the presence
of placental tissue that extends over or near the internal
cervical os. So really straightforward. In a normal pregnancy, the
placenta is usually right around the top of the uterus.
In placenta previa, the placenta is at the bottom of
the uterus, sometimes covering the entire cervical oss. This can
cause a number of problems which will go over but
again placenta previa. The placenta is in the wrong spot,
plugging up the internal cervical oss and varying degrees. Now
why this happens, we're not really sure, which is good news.
From an exam standpoint. As one less thing to remember.
But one hypothesis is that the upper uterine cavity where
the placenta normally in plants, is not well vascularized, whether
this is due to previous surgery, multi parity, or other issues.
So I do have a quick knuomonic placenta abruption which
we just went over. The placenta was moving away from
the uterus. Remember it is kind of being ripped apart
and placenta previa. The placenta is plugging up the uterus.
So placenta abruption placenta away. Placenta previa placenta plug essentially,
so placenta abruption has an a. Remember the placenta is
moving away from the uterus. Placenta previa has a p
so remember the placenta is plugging up the uterus. Just
another way to help you remember the differences between the two.
All right, So with placenta previa, what are some risk
factories you should know? There's three main ones to focus on.
Starting with a previous placenta previa. Again, like so many
things in medicine, if you had it before, higher risk
of having it again. Previous cesarean birth and then finally,
multiple gestation, so carrying more than one baby at a time, twins,
et cetera. One study found placenta previa was forty percent
higher among twin berths than among singleton berths. There's other
risk factors, increasing maternal age, smoking, cocaine use, male fetus,
but focus on the three we went over above, if
you're even going to bother them memorizing risk factors at all,
because to be honest, they're not the highest deeled thing
to know. With that being said, though, let's talk about
something that is very high yield, and that's the clinical manifestations.
So let's start with the fact that this may be
an asymptomatic finding on routine ultrasound at approximately eighteen to
twenty weeks of gestation. So the majority of placenta previus
will be an asymptomatic finding on mid trimester ultrasound examination,
and luckily about ninety percent identified on ultrasound at eighteen
to twenty weeks will resolve before delivery, So many women
may be asymptomatic. But this isn't what you should remember
for the exam. On the exam, they're not going to
give you an asymptomatic patient what they're going to give
you is a patient with painless vaginal bleeding. Painless I'll
repeat it again, painless vaginal bleeding. In the second half
of pregnancy, the most common symptom of placenta previa is
painless vaginal bleeding, which occurs in up to ninety percent
of cases. Compared this to placental abruption, which again, remember
more often than not had painful bleeding. So placenta previa
painless bleeding. Now in real life, ten to twenty percent
of patients with placenta previa may have some pain from
uterine contractions, et cetera. But we're preparing for an exam,
and for an exam, remember the most common which is
painless vaginal bleeding. So how do you remember that? While
instead of placenta previa, remember it as placenta stevia. Placenta
previa is now placenta stevia. Stevia as we know, is
that sugar free or a sugarless sweetener, and placenta previa
is the pain free or painless vaginal bleeding. It works
for me. I know it's a little weird, but hopefully
it helps you too. Placenta stevia sugar free sweetener pain
free vaginal bleeding. Okay, diagnosis, Let's first talk about what
you do not want to do, and this will often
be tested on. So you don't want to perform a
digital vaginal exam anytime there is any vaginal bleeding in
the second or third trimester. A digital examination is absolutely
contraindicated until you perform ultrasound and rule out a placenta previa.
If you perform a digital vaginal exam on a patient
with placenta previa, remember the placenta. It's in the wrong spot,
positioned low in the uterus, covering or near the cervix,
and a digital exam can reach this area and dislodge
the placental's attachment site, causing severe bleeding. So remember that
because it definitely could be a question. Okay, So now
that we know what we should not do, what should
we do to help make the diagnosis, Well, that's using ultrasound.
So this is how you diagnose placenta previa. Ultrasound is
what you need to know. So you'll usually start with
trans abdominal ultrasound as a screening test, and then the
gold standard is with transvaginal ultrasound, which provides better detail
and better defines the placental position. Now we just said
never do a digital vaginal exam on a patient with
a suspected placenta previa, Why the heck can we do
a transvaginal ultrasound? While with a transvaginal ultrasound you're able
to visualize the anatomy, so you're not going in blind,
and the optimal position of the vaginal probe is actually
far enough away from the cervix to make this a
safe test. So when you do the ultrasound, what are
you looking for to confirm the diagnosis? So that's going
to be placental tissue visualized over the internal cervical oss.
So again diagnosis, do not perform a digital vaginal exam,
do perform an ultrasound. What about treatment next? Just like
with placental abruption, I don't think many or any questions
will be asked about management, but just so you have
a general idea. In asymptomatic patients where placenta previa is
seen on routine ultrasound at eighteen to twenty two weeks,
close monitoring is an option. If you have a mother
with an actively bleeding placenta previa, this is a potential
obstetric emergency, so monitoring maternal hemodynamic status, blood transfusions, monitoring
fetal heart rate. Once the bleeding has resolved in some patient's,
outpatient management is reasonable. You want to recommend to avoid
excessive physical activity, avoid sexual intercourse. Some women will receive
antenatal corticosteroid therapy and then when delivery is recommended in
some patient's, vaginal delivery can be an option, but quite
often a Cissaian birth is recommended. Okay, So, placenta previa.
This is the abnormal presence of placental tissue that extends
over or near the internal cervical oss. While this may
be an asymptomatic finding on routine exam, the classic symptom
of placenta previa that you will not forget is painless
vaginal bleeding. Up to ninety percent of persistent cases will
have painless painless painless fagional bleeding. Remember placenta stevia sugar
free pain free diagnosis. Do not perform a digital vaginal exam,
Do perform an ultrasound treatment, manage the bleeding, observe and
deliver when appropriate. That's placenta previa. Now let's do a
quick recap of what I feel are the highest yield
things to know for both placental abruption and placenta previa. Okay, So,
Placenta abruption is a premature separation of the placenta from
the uterus. Placenta previa is abnormal placental tissue over or
near the internal cervical os So placenta abruption placenta moving
away from the uterus. Placenta previa is plugging up the uterus.
Remember placental abruption has an A, so placenta is moving
away from the uterus, and placenta previa has a p
so the placenta is plugging up the uterus. Next presentation
placental abruption painful bleeding cramping along with rigid hypertonic uterus
on physical exam, remember your placental crab eruption and then
placenta previa remember painless faginal bleeding. Remember placenta stevia sugar
free pain free. Remember placenta previa. You do not perform
a digital vaginal exam as this can cost of your hemorrhage.
And finally, with placental abruption, a retroplacental hematoma is the
classic ultrasound finding. So those are the most important things
to remember about these two conditions. Let's do some questions.
Next question one, A thirty two year old G three
P twoter woman presents to the emergency department at twenty
eight weeks gestation with painless vaginal bleeding that started an
hour ago. She denies any contractions, abdominal pain, or trauma.
Her pregnancy has been uncomplicated until now. On examination, she
is hemo dynamically stable and the fetal heart rate is
one hundred and forty five beats per minute. Which of
the following should be avoided in the workup of this patient?
A trans abdominal ultrasound, B, transvaginal ultrasound, C digital vaginal
examination or d fetal heart rate monitoring? Again, which of
the following should be avoided in the workup of this
patient A trans abdominal ultrasound, B, transvaginal ultrasound, C, digital
vagili examination or DE fetal heart rate monitoring. All right,
So I'm sure you know the answer to that one,
and that is going to be CE digital vaginal examination.
All right. So we have a pregnant patient with vaginal
bleeding after twenty weeks tessation. G three P two minting
three pregnancies and two berths at term. The vignette clearly
states there is no pain or contractions, so while we
can't definitively say that this is a placenta previa without imaging,
it should definitely be high on the list of differentials.
Most important thing is to remember that anytime a patient
has vaginal bleeding late in pregnancy, you do not perform
a digital vaginal examination until you rule out a placenta previa,
as this can lead to severe hemorrhage. So the other
answer is ultrasound. For Answers A and B, this is
first line imaging to assess placental position that includes transvaginal ultrasound,
which can be safely performed even with placenta previa. And
then finally, fetal heart rate monitoring always appropriate with active
vaginal bleeding and a pregnant patient, So again answers CEE,
digital vaginal examination is the only choice that is absolutely
contraindicated until previa is ruled out. Question two. A thirty
five year old G four P three female currently thirty
six weeks pregnant, presents the emergency department after being involved
in a motor vehicle accident she's complaining of severe abdominal
pain and vaginal bleeding. She admits to using cigarettes and
cocaine during her pregnancy. Abdominal exam reveals a rigid uterus
with palpable uterine contractions and blood is observed in the
vaginal vault. If an ultrasound were performed, which of the
following findings would be most consistent with the likely diagnosis?
A placenta covering the internal OS and extending posteriorly B
low lying placenta one centimeter from the internal oss. C
retro placental hematoma, D normal placental position with no abnormalities. Again,
which of the following would be most consistent with the
likely diagnosis if ultrasound were obtained. A placenta covering the
internal OS and extending posteriorly B low lying placenta one
centimeters from the internal oss see retroplacental hematoma or D
normal placental position with no abnormalities. Okay, that is going
to be ce retroplacental hematoma. So first, what is the
likely diagnosis in this patient? Well, first, does this patient
have She does? She has crab, which again we know
is contractions. She has a rigid uterus. She has abdominal
pain and she has bleeding, so a suspicion for a
placental abruption should be high. The vignette also mentions she
used in a motor vehicle accident, which we know is
a risk factor for placental abruption, and then finally it
mentions cocaine and cigarette use. Highly likely this patient has
a placental abruption, and as we discussed earlier, while this
may not be found in all patients, a retroplacental hematoma
or clot is a classic ultrasound finding and strongly supports
the diagnosis question three for the patient. Reference in the
previous question, what underlying pathophysiological mecha mechanism is most likely
responsible for their condition? So in the patient we just
mentioned what underlying pathophysiological mechanism is most likely responsible for
their condition? Okay, and remember that is going to be
a rupture of maternal vessels in the decidua based sallus.
So remember in a placental abruption, vessels in the decidua
bas salice rupture. These ruptured vessels bleed and accumulate, which
eventually causes the placenta to separate and peel away. Okay,
so I hope that was helpful. Thank you so much
for listening. If it's helping you, please leave a review
in the podcast comments and if you really like it,
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you so much again