OB: LATE PREGNANCY THIRD TRIM BLEEDING and POSTPART HEMM Flashcards
Previa means …
Previa means “over the cervical os.”
Why do we get bleeding in placenta and vasa previa?
As the cervical os undergoes effacement and dilation, the adherent placenta or blood vessels, which are not built to dilate, shear and rip apart, and baby bleeds.
How can placenta previa and vasa previa present in labor?
PAINLESS vaginal bleeding, there may be pain from contractions but not from the bleeding
How can vasa previa arise?
velamentous insertion of the cord or placental migration resulting in apoptosis over the os with residual vessels.
How will placental abruption present?
Ripping the placenta off hurts. Therefore, placental abruption presents with painful vaginal bleeding. The cause of abruption is some severe force, either a hypertensive emergency (cocaine use) or deceleration injury (motor vehicle collision). Because there are no contractions, by definition, abruption occurs before labor begins. There will be no contractions experienced by mom, only painful vaginal bleeding and signs of maternal blood loss.
As opposed to placenta previa or vasa previa, the bleeding with previa accompanies labor whereas abruption does not
In a TOLAC, what kind of incision provides lower risk?
previous transvere
What are the 4 Ts of postpart hemm?
Tone, Tissue, Trauma,Thrombin
tone(uterine atony, uterine inversion), tissue (retained placental parts and the placenta accreta spectrum), trauma (lacerations or contusions of the cervix or vagina), and thrombin (DIC or other inflammatory pathology that presents like DIC).
What does uterine atony result from?
Uterine atony results from prolonged delivery (tired uterus and mom) or, in the case of oxytocin induction, the withdrawal of oxytocin too soon after the delivery of the placenta.
How do we treat uterine atony?
The goal is to get the myometrium to continue to contract down and for the bleeding to stop. Recall from the Basic Sciences that the myometrium contracts in response to stimulation by CAPs, such as the oxytocin receptor and prostaglandin E1, E2, and F2αreceptors. First-line therapy is a strong uterine massage, manipulation of the uterus by a human hand. For pharmacological intervention, first-line therapy is oxytocin, which stimulates oxytocin receptors on the myometrium. After oxytocin is the ergot alkaloid methylergonovine, a medication that causes uterine contraction and vasoconstriction (which must be avoided in hypertension). The final therapy is the prostaglandin analog to F2α, cataboprost,or simply prostaglandinF2α(which must be avoided in asthmatics). Historically, and in patients without intravenous access, the PGE1 analog misoprostol can be administered vaginally or orally. Hysterectomy is the definitive treatment in all cases of postpartum hemorrhage, as the uterus is the source of the bleeding.
What increases risk for uterine inversion?
Risk of uterine inversion increases with oxytocin use and umbilical cord traction.
How does retained placenta parts increase risk for hemmorage?
Failure of the entire placenta to deliver fully can result in massive hemorrhaging, even if only a small amount of placental membrane or a single cotyledon is retained. Every placenta must be carefully inspected after delivery to see if any part of it appears to be torn or incomplete. Vessels extending to the edge of the placenta indicate a torn placenta, and what it was torn from may still be retained in the uterus. A bedside ultrasound is performed (unless the entire placenta fails to deliver, in which case it is obvious that the placenta is retained).
What is the placentra accreta spectrum?
Placenta accreta is on the myometrium, having eroded the entire endometrium. Placenta increta burrows into the myometrium. Placenta percretaburrows through the myometrium and potentially into nearby organs (rectum, bladder).
What increases risk for accreta?
Risk increases with multiparity—the same patient profile and rationale as placenta previa. Like placenta previa, placenta accreta should be diagnosed during an antenatal ultrasound far before delivery. This condition is so dangerous and its management so difficult that just having the diagnosis necessitates a planned peripartum hysterectomy. For a woman to present with postpartum hemorrhage and placenta accreta, she would have to go without health care for the entirety of her pregnancy.
How does pph from a coagulopathy come about?
Rarely, postpartum hemorrhage results from a previously undiagnosed inherited coagulopathy, such as Von Willibrand’s disease or hemophilia. If this is the case, it should be identified during the first pregnancy, as she would otherwise already be diagnosed with the condition due to PPH in a previous pregnancy. More commonly, it results from preeclampsia, severe infection, or disseminated intravascular coagulopathy (DIC) and no cause can be discovered.
How do we deal with hemmorgae?
What are the grades of perineal lacerations?
Perineal lacerations are graded according to the extent of the trauma. Grade 1 involves only the vaginal mucosa or perineal skin. Grade 2 is deeper, involving the perineal muscles but not the anal sphincter. Grade 3 penetrates the anal sphincter, but not through it, so no anal mucosa is involved. Grade 4 connects the two mucosae—tearing through vaginal mucosa, perineal muscles, the anal sphincter, and the anal mucosa.
