Third Trimester and Pospartum Bleeding Flashcards
What is it called when the placenta implants over the cervical os?
Placenta previa
What is it called when the placenta implants over the cervical os?
Placenta previa
What is a complete or total previa?
Placenta completely covers the os (20-40%)
What is a partial previa?
Placenta partially covers the internal os (30%)
What is a marginal previa?
The edge of the placenta extends to the margin of the internal os (30-50%)
How are people with placenta previa typically delivered and why?
Usually C-section because of bleeding
What is the measure called of how many cm above or below the ischial spines a baby is?
Station
- is below
- is above
What is it called when the placental lies in the lower uterine segment, but doesn’t extend to the cervical os?
Low lying placenta
-Not really an issue… just repeat US at 28 weeks to make sure it hasn’t moved towards the os
What is the premature separation of the normally implanted placenta from its attachment to the uterus?
Placenta abruptio
What are 3 things that can commonly cause placenta abruptio?
Trauma, high BP, or crack cocaine
What is the complete separation of the uterine musculature through all of its layers?
Uterine rupture
Where does a uterine rupture commonly happen?
At the site of a previous surgery (C-section, fibroids removed ect) becuase it’s a weak point in the uterus… in the situations, just do a C-section
What is considered pospartum hemorrhage?
Blood loss in excess of 500mL vaginal delivery or 1000mL for a cesarean
What is it called when the placenta is directly attached to the myometrial wall?
Placenta accreta
What is absent in a placenta accreta?
No decidua basalis (absent Nitabuch’s layer)
What is it called when the placenta invades the myometrium?
Placenta increta
What is it called when the placenta penetrates the myometrium to the serosa or beyond?
Placenta percreta
What is is called when the vessels of the umbilical cord insert between the layers of the amnion and chorion away from the placenta?
Velamentous cord insertion
What happens in a vasa previa?
The unprotected vessels from a velamentous insertion pass over the os… they are predisposed to rupturing
What things increase in pregnancy?
- Maternal blood volume (up by 40%)
- Plasma volume
- Erythrocyte volume
- 2,3 DPG
- Heart rate (10-15bpm)
- Stroke volume
- Cardiac output (30-40%)
What things decrease in pregnancy?
- Maternal BP
2. Systemic vascular resistance
Why do you not have to treat anemia in preggo ladies until Hb hits like 10ish?
Because is it a physiological dilution of their blood… even through norm Hb is around 12-16, they are chill until like 10 because of this and won’t show shock systems until they have lost a lot of blood
In a normal person, what is the blood flow rate through the uterine artery? What about a preggo lady?
- Normal is 60cc per min
- Preggo is 6000cc per min
- AKA, you nick the uterine artery in a prego lady they bleed out (exanguinate) in about 10 min… DON’T DO IT
Pregnancy is associated with what % increase in total blood volume by what week gestation?
40%, 13th week
What will the blood volume increase to in an average sized female?
6000mL
Antepartum and pospartum bleeding issues complicate what % of pregnancies?
4% each
What are the top 3 causes of maternal death in the US?
- Embolism
- HTN disease
- Hemorrhage
He gave us a hemorrhage classifications in preggo chart…what was the main thing we were supposed to take away from it?
That preggo ladies can loose up to 1000cc blood without showing any symptoms
-Said we didn’t need to know details, but take a glance at …TRUST NO ONE
What are the 2 most common causes of antepartum bleeding?
- Placenta previa (20%)
2. Placenta abruption (30%)
What are the other 50% of causes of antepartum bleeding that aren’t as common?
- Uterine rupture
- Fetal vessel rupture
- Cervical or vaginal lacerations
- Cervical or vaginal lesions including cancer
- Congenital bleeding disorder
- Unknown
You ask about abdominal pain, contractions, placenta previa, c sections or other prior uterine surgeries, smoking, cocaine, or bleeding disorders as part of what?
History portion of the initial evaulation for antepartum hemorrhage
What physical things do you check when evaluating for antepartum hemorrhage?
Vitals, amount of bleeding, uterine tenderness
True or False: When evaluating for antepartum hemorrhage, you check the cervix?
FALSE- DO NOT CHECK CERVIX UNLESS PLACENTA PREVIA HAS BEEN RULED OUT
-You roll with a US or careful spec exam (only open things up a bit to check for the cervix to see if it’s dilated with placenta pouring out through it waiting to explode at you)
What are 3 diagnostic things done for anterpartum hemorrhage evaluation?
- CBC and coag profile
- US
- Monitoring
What is the most accurate means of determining the cause of bleeding, but will still miss 50% of abruptions?
US- It is good for previa, but harder with abruption
What is seen in 1/200 deliveries and accounts for 20% of all antepartum bleeding?
Placenta previa
What are the 3 types of placenta previa?
- Complete
- Partial
- Marginal
What are 5 predisposing factors to placenta previa?
- Previous C-section
- Multiparity
- Multiple gestation
- Advancing maternal age
- Previous placenta previa
What are some complicating factors with placenta previa?
- 1/25 will have an underlying accreta
- 20% will have an underlying IUGR
- 2x higher rate of congenital abnormalities
- 30% malpresentation
- Higher incidence of PPROM
- Risk of Vasa Previa
What is PPROM?
Pre-term, premature rupture of membranes
-When water breaks under 37 weeks
What is PROM?
Pre-term rupture of membranes
-Full term, water breaks, no labor, contractions
What does the cervix have to do to deliver a baby?
Dilate to 10cm & Efface
Why can a low implantation or low-lying placenta not be bad?
Because the uterus grows from the upper 2/3 and up… so as the uterus grows, the placenta might grow “up” and move out of the way as the pregnancy progresses
Why is a vag delivery possible with marginal placenta previa?
Because the babies head could possible tamponade off of the vag and allow for the baby to sail on out
What is IUGR?
Intra-uterine growth restriction
If something happens once?
IT IS LIKELY TO HAPPEN AGAIN
What is the classical presentation of placenta previa?
Painless, bright red bleeding
What % of placenta previas are associated with contractions?
20%
What are the 2 types of US to diagnose placenta previa and what is the % effective?
- Transabdominal- 95%
2. Transvaginal- 100% (but this could precipitate bleeding)
What is done is US is inconclusive for placenta previa?
Double-set up exam… get yo lady in stirrups to examine, but be ready for a C-section too just in case
What are the first 2 things to do with placenta previa?
- Stabilize momma: IV, CBC, Type and Cross
2. Assess baby: Monitor, US, determine gestational age/maturity, fetal HR monitoring
If momma is stable and baby is preterm, what do you do with a placenta previa?
- Amniocentesis for lung maturity
- If mature: Delivery by C-section
- If immature: Bed rest, transfusions
In a placenta previa, if the baby is immature and you are trying to hold it in, what are 3 drug considerations to remember?
- Caution use of tocolytics: Magnesium sulfate id DOC
- Beta mimetics could mask tachycardia
- RHOGAM BABY
When is Rhogam given?
Rh- momma, Rh+ baby
-Give at 28 weeks… after birth, if baby is Rh-, everything is happy and merry… it baby is Rh+ another dose Rhogam within 72 hours of delivery
-ALWAYS DOCUMENT THAT YOU OFFERED RHOGAM
1 vial of Rhogam covers how much mixing of maternal and fetal blood?
15cc
What is the blood test to determine the amount of fetal Hb transferred to maternal blood?
Kleihaure- Betke
Soooo… since Rhogam vial only covers about 15cc mixing, what do you do if this Kleihaure-Betke test shows that more blood has mixed for whatever reason?
GIVE MORE VIAL OF RHOGAM…whoooooop
If momma or baby is unstable with placenta previa, what do you do?
C-SECTION
If where is a low lying placenta, momma and baby are stable… what can you do?
Attempt a vag delivery
- Fetal head should tamponade the bleeding
- Buuuuut… do a double set up with prep for a C-section
What happens in 1/120 births, with a fetal death rate of 1/500, and 80% occur prior to the onset of labor?
Placental abrupion
What is the age of viability?
24 weeks
What is a normal baby HR?
110-160
What is used to tell how far along baby is?
Uterine height
If the baby is below the umbilicus, how far along is it?
Under 20 weeks- NO C-SECTION
How do you save baby?
SAVE MOMMA (#1 COD for fetal is maternal shock)
What are risk factors for placenta abruption?
- Maternal hypertension
- Cocaine abuse, especially “crack”
- Trauma
- Smoking
- Polyhdraminios and multiple gestation- rapid decompression of an over-distended uterus
- Previous Abruption 5% recurrence, if two or more 25% recurrence rate
What is the gestational age where the baby should be okay?
Over 32 weeks…under this.. significant morbiditiy
Why can polyhydraminos cause placenta abruption?
With lots of amniotic fluid, when the water breaks there is a rapid decompression of the uterus and the placenta can just detach off
What is the most common cause of DIC in pregnancy?
Placenta abruption
What are complicating factors with placenta abruption?
- Perinatal mortality rate due to abruption, is 35%.
- Accounts for 15% of third trimester stillbirths.
- 15% of livebirths have neurologic damage.
- Most common cause of DIC in pregnancy.
- Hypovolemic shock, renal failure.
- Sheehan’s syndrome
What is the MOA of placenta abruption?
- Hemorrhage into the decidua basalis with formation of a hematoma.
- The seperation of the decidua from the basal plate perpetuates itself causing further separation as well as compression and destruction of tissue.
- If the blood dissects upward into the fundus, it will cause a concealed hemorrhage.
- If the blood dissects downward it will be revealed.
-Sorry…too lazy to make fancy questions out of this… and he didn’t spend time talking about it anyways
What is it called when there is a blueish purple discoloration to the uterus caused by blood dissecting into the myometrium?
Couvelaire Uterus
-Blueberry appearing–> Blood into myometrium after abruption
If a lady has a couvelaire urterus, what does she need?
Hysterectomy
What is the hallmark of placenta abruption?
Painful vaginal bleeding in association with uterine tenderness, hyperactivity, and increased tone
What makes the diagnosis of placenta abrption?
Clinical… US isn’t very affective
What % of ladies with placenta abruption have vag bleeding and what does it look like?
80% and it’s dark red (because it dissected, it is deoxygenated by the time it gets out)
What are other symptoms/issues seen with placenta abruption?
- Pain: 66%
- Fetal Distress: 60%
- Uterine Hyperactivity: 34%
- Fetal Demise: 15%
What will the abdomen be like with a placental abruption?
HARD BELLY
-It will feel like a contraction that isn’t going away
What are 6 aspects of management for placental absruption?
- Stabilize Mother
- IV’s
- Serial Coagulation Profiles
- Keep blood products on hand (DIC)
- Fetal Monitoring
- Vaginal Delivery preferred route. C-section for obstetrical reasons only
What is the complete separation of the uterine musculature through all of it’s layers?
Uterine rupture
Where is the fetus in uterine rupture?
Extruded into the abdomen
What is the incidence of uterine rupture?
0.5%
When can uterine rupture occur?
During or before labor, or at the time of delivery
What % of uterine ruptures are associated with previous uterine scar?
40%
- C/S most common- with prior LTCS -0.5% risk, with a previous vertical incision 5% risk.
- Myomectomy
- Metroplasty
What % of uterine ruptures occur in previously unscarred uterus?
60%
-GRand multip, ect… I think this was 5+ pregnancies?
What are 2 complicating factors with uterine rupture?
- Maternal mortality 1%
2. Fetal mortality 32%
What are 6 things used to diagnose uterine rupture?
- Must have high index of suspicion.
- Sudden onset of intense abdominal pain and vaginal bleeding
- Hyperventilation, agitation and tachycardia
- After rupture, momentary relief of pain but it returns.
- Fetal Distress
- Palpable fetal parts in abdomen.
What is done for uterine rupture?
- Immediate laparotomy
- Usually a total abdominal hysterectomy is performed (TOC)
- Possibly a debridement of rupture site and primary closure if fertility is still desired by patient
Where are the contractile fibers located in the uterus?
Upper 2/3
What is removed in a TAH?
Uterus and cervix (subtotal leaves cervix and takes uterus)
If you had a C-section and the cut up high, can you ever do a vag delivery?
Probs not… if you had a low transverse incision, possible (because of where contractile fibers are located
Just gonna toss in some stats about vasa previa…
- Incidence - 1/5000.
- Rupture 0.1 to 0.8%.
- 50% fetal mortality.
- If membranes rupture, 75% mortality.
What is the % indicence of postpartum hemorrhage?
4%
What is the physiology of postpartum hemorrhage?
The uterus fails to contract around the myometrial spiral arterioles and decidual veins at the attachment site after placental separation