4/14 Complications + Pathophysiology of Pregnancy Flashcards
(40 cards)
causes of maternal mortality in us?
- infection
- Hemorrhage
- HTN d/o of pregnancy
- Venous thromboembolism
- Indirect causes such cardiovascular disease and non-obstetric injuries
What is Puerperal fever in pregnancy?
defined as T ≥100.4°F (38°C) that occurs for ≥2 consecutive days during the first 10 postpartum days
What are causes of puerperal sepsis?
complications?
causes:
- endometritis (infection in the uterus)
- perineal wounds
- C-section wounds
complications:
- risk of septic shock
- pelvic thrombophlebitis
- pelvic abscess
What is endometritis and how does it occur?
endometritis (infection in the uterus)
- occur due to ∆s at the placenta-maternal interface, where
-
alkaline amniotic fluid, blood, and lochia (vaginal discharge) neutralize vaginal pH allowing bacterial growth
- normally, vagina acidity (pH 4-5) usually protects against overgrowth of bacteria
-
alkaline amniotic fluid, blood, and lochia (vaginal discharge) neutralize vaginal pH allowing bacterial growth
- Necrotic endometrium and placenta fragments make the uterine cavity favorable for the growth anaerobic bacteria
What are the common pathogens of endometritis?
70% caused by mixed anaerobic organisms
risk factors for endometritis?
- Poor nutrition and hygiene
- Premature or prolonged rupture of membranes
- Chorioamnionitis
- Prolonged labor
- Numerous vaginal examinations or manual removal of placenta
- C-section
- Retained placental fragments or fetal membrane
What are the major causes of
ANTEPARTUM HEMORRHAGE?
POSTPARTUM HEMORRHAGE?
ante: placenta previa + placenta abruptio
post: uterine atony (80% of cases)
What is placenta previa?
How do you tell if a woman has it?
“latin root of previa – going before”
placenta is partially or wholly in the lower uterine segment, over the cervical os
presentation: painless vaginal bleeding (70%)
What are the 4 types of placenta previa?
- Total/complete - placenta covers internal os completely
- Partial - placenta covers internal os partially
- Marginal - lower edge of placenta reaches internal os, but does not cover it
- Low-lying - Placenta is in lower segment, but the lower edge does not reach
Risk factors for placenta previa?
- Multiparity/multi-gestation – women with a lot of babies
- Older maternal age
- Prior hx of placenta previa
- Prior C-section (placenta may adhere to scarred uterus)
- Tobacco use
How do you diagnose placenta previa?
US (transabdominal or transvaginal)
What is placenta abruptio?
How does a patient typically present?
premature separation of the “normally” implanted placenta due rupturing of maternal spiral arterioles in the decidua basalis, where it interfaces with the anchoring villi of the placenta; accumulating blood separates the decidua from its placental attachment to the uterus
presentation: painful vaginal bleeding, uterine tenderness and contractions
How does Placental abruptio form?
hypothesized to be an underlying abnormality in how the placenta has attached to the decidua or an inherent weakness or abnormality in the spiral arterioles, or trauma
What happens if there is a complete placental abruptio?
- fetal death - detached portion of the placenta is unable to exchange gases and nutrients; when the remaining fetoplacental unit is unable to compensate for this loss of function
- placenta will also become infarcted since it’s not being perfused properly
2 types of placental abruptio?
- Concealed hemorrhage occurs when blood dissects upward toward the fundus without vaginal bleeding
- External or revealed hemorrhage occurs when blood dissects towards the cervix; presents with vaginal bleeding
Risk factors for placental abruptio?
- Maternal HTN
- Placental abruption in a prior pregnancy
- Trauma (blunt, falls, MVC) – big risk factor
- Polyhydramnios with rapid decompression – rapid ∆ of the placental shape -> shearing force
- Premature rupture of membranes
- Tobacco use
How do you diagnose placenta abruptio?
US (identifies abruption only 50% of the time!)
- US is indicated to exclude previa, since abruptio may coexist with a previa
When does postpartum hemorrhage usually occur?
how is it diagnosed?
- usually occurs immediately following delivery
- Hemorrhage criteria:
- 10% drop in hematocrit
- need for transfusion
- signs/sx of acute anemia after a vaginal delivery or C-section
Major cause of postpartum hemorrhage and how does it occur?
Uterine atony (80%) ****
- Normally the myometrium contracts around the myometrial spiral arterioles and decidual veins of the intervillous spaces and acts as a physiologic “ligature” to cut off blood flow
- failure of the uterus to contract after placental separation (atony) puts these vessels at risk of bleeding post-partum
Other potential causes post-partum hemorrhage
- Genital tract trauma/laceration during delivery
- Cervix, vagina, perineum, extension of hysterotomy with laceration of uterine arteries
- Retained placental tissue
- Low placental implantation in the uterus
- Uterine inversion –uterus inverts as the placenta is delivered
- Coagulation disorders
UTERINE ATONY is the major cause
Risk Factors of postpartum hemorrhage?
- Prolonged labor, augmented labor, or rapid labor
- History of postpartum hemorrhage
- Overdistended uterus (macrosomia, twins, hydramnios) – uterus doesn’t have the ability to contract down well
- Operative delivery
- Magnesium sulfate (agent used to relax smooth muscles)
- Infection
- Chorioamnionitis
What are the major hypertensive d/o of pregnancy?
pre-eclampsia + eclampsia
How often does hypertensive d/o in pregnancy occur?
occurs in 7-10% of pregnancies; accounts for ~20% of maternal deaths in US (usually due to maternal-cerebrovascular accidents)
What are the characteristic features of pre-eclampsia?
HTN, proteinuria, edema (leads toweight gain)
