#183 Postpartum Hemorrhage Flashcards
What is the definition of maternal hemorrhage?
Cumulative blood loss of greater than or equal to 1,000mL or blood loss accompanied by signs or symptoms of hypovolemmia within 24 hours after birth process
What is the leading cause of maternal mortality worldwide?
Hemorrhage
What secondary sequelae from maternal hemorrhage exist?
ARDS, shock, DIC, acute renal failure, loss of fertility, and pituitary necrosis (Sheehan syndrome)
What is rate (% of total mortalities and per 100,000 live births) of maternal mortality from hemorrhage?
Slightly more than 10% of maternal mortality due to hemorrhage. 1.7 deaths per 100,000 live births (in 2009)
How does definition of postpartum hemorrhage change based on mode of delivery?
It does not. 1,000mL for both.
Traditionally was 500cc for vaginal, 1000cc for CS
Definition of PPH for vaginal delivery is 1000cc blood loss or greater, previously was 500cc. Is blood loss of 500-1000cc after vaginal delivery normal?
No. Should be considered abnormal and should serve as an indication for provider to investigate the increased blood deficit
What decrease in hematocrit has been used to define postpartum hemorrhage? What are limitations of this?
Decrease of 10%. Measurements of hematocrit concentrations are often delayed, may not reflect current hematologic status, and are not clinically useful in acute setting
At what level of blood loss (mL and % total volume), would you expect a healthy postpartum patient to start developing tachycardia and hypotension?
1,500mL or more of blood, about 25% of total blood volume.
What is the definition of secondary postpartum hemorrage?
Excessive bleeding that occurs more than 24 hours after delivery and up to 12 weeks postpartum
What are the etiologies of primary (within 24h) postpartum hemorrhage?
Uterine atony, lacerations, retained placenta, abnormally adherent placenta (accreta), defects of coagulation (eg, DIC), uterine inversion
What are the etiologies of secondary (>24h, <12wks) postpartum hemorrhage?
Subinvolution of the placental site, retained POCs, infection, inherited coagulation defects
What percent of cases of postpartum hemorrhage are caused by uterine atony?
70-80%
What is the most common cause of postpartum hemorrhage?
Uterine atony, 70-80% of cases
What are risk factors for postpartum uterine atony leading to postpartum hemorrhage?
Prolonged use of oxytocin, high parity, chorioamnionitis, general anesthesia, over-distended uterus (twins or multiple gestation, polyhydramnios, macrosomia), uterine inversion (excessive umbilical cord traction, short umbilical cord, fundal implantation of placenta)
What are risk factors for genital tract trauma leading to postpartum hemorrhage?
Episiotomy, operative vaginal delivery, precipitous delivery, cervical, vaginal, and perineal lacerations, uterine rupture
What are risk factors for retained placental tissue leading to postpartum hemorrhage?
Retained placenta, succenturiate placenta, placenta accreta, previous uterine surgery, incomplete placenta at delivery
What are risk factors for abnormalities of coagulation leading to postpartum hemorrhage?
Preeclampsia, inherited clotting factor deficiency (von Willebrand, hemophilia), severe infection, amniotic fluid embolism, excessive crystalloid replacement, therapeutic anticoagulation, fetal death, placental abruption, hemorrhage
How accurate are risk assessment tools at identifying patients who will experience a significant obstetrical hemorrhage? What percentage does it identify that does not experience hemorrhage?
Identify 60-85% who had hemorrhage. Identified more than 40% of women who did not experience hemorrhage as high risk.
What components make up active management of third stage of labor?
- Oxytocin administration
- Uterine massage
- Umbilical cord traction
What is the dosing of oxytocin (IV and IM) for prophylaxis during third stage of labor?
Dilute IV infusion (bolus dose of 10u), or IM injection of 10u
When should prophylactic oxytocin be administered during third stage of labor to help prevent postpartum hemorrhage?
Timing has not been adequately studied or found to be associated with difference in the risk of hemorrhage.
Does nipple stimulation or breastfeeding decrease the risk of postpartum hemorrhage?
Per Cochrane review, it does not
What treatment options are available for management of postpartum hemorrhage due to uterine atony?
Administration of uterotonics or pharmacologic agents, tamponade of the uterus (eg, intrauterine balloon), surgical techniques to control bleeding (eg, B-Lynch pro3-25%cedure), embolization of pelvic arteries or, ultimately, hysterectomy
After uterine atony is identified in setting of postpartum hemorrhage, what are the first steps?
Empty bladder, bimanual pelvic exam, removal of intrauterine clots, uterine massage
How often is a second uterotonic (after oxytocin) required during a postpartum hemorrhage?
3-25% of cases
Which uterotonic is most effective?
According to 2015 systematic review, lack of evidence that suggests which additional uterotonics are most effective (after oxytocin)
What is the initial management of lower uterine segment dilation and atony (fundus firm)?
Manually remove any clots and use bimanual compression to reduce blood loss while waiting for the uterotonic agents to work
Are genital tract lacerations more commonly venous or arterial bleeding?
Venous
How do you manage a post vaginal delivery patient with suspected uterine artery laceration?
Interventional radiology or surgical exploration and ligation
What signs/symptoms may make you concerned for a genital tract hematoma after vaginal delivery if you’re unable to see it?
Labial, rectal, pelvic pressure or pain, vital sign deterioration. Also need to consider possible retroperitoneal or intraperitoneal bleeding.
What are risk factors for a genital tract hematoma formation during vaginal delivery?
Precipitous delivery or operative delivery
How do you manage a genital tract hematoma after delivery?
Most can be managed conservatively. If rapidly expanding or vital sign deterioration > interventional radiology arterial embolization vs exploration with suturing and packing
True or false, you should inspect the placenta for completeness after all deliveries?
True, but even if appears intact, may be additional remaining POCs (eg, succenturiate lobe)
How do you diagnose retained placental tissue at time of delivery?
Ultrasonography or intrauterine manual examination
How should you remove retained palcenta at the time of delivery?
First step is attempt manual removal. Then either a “banjo” curette or large oval forceps (Sopher or Bierer) can be used.
How does placental abruption typically lead to postpartum hemorrhage?
Often associated with uterine atony 2/2 extravasation of blood into myometrium (Couvelaire uterus), and DIC and hypofibrinogenemia.
How does placental abruption classically present?
Vaginal bleeding, frequent uterine contractions (tachysystole; high-frequency, low-amplitude ctx), and pain.
What % of postpartum hemorrhage cases that require massive transfusion are caused by placental abruption?
17%
Is amniotic fluid embolism common?
No
Is amniotic fluid embolism predictable?
No
Is amniotic fluid embolism preventable?
No
What triad makes up amniotic fluid embolism?
hemodynamic and respiratory compromise in addition to strictly defined DIC
What are the uterotonic medications?
oxytocin, methylergonovine, 15-methyl prostaglandin F2, and misoprostol