Placental Abruption Case File
Eugene C. Toy, MD, Patti Jayne Ross, MD, Benton Baker III, MD, John C. Jennings, MD
CASE 11
A 22-year-old G2P1 woman at 35 weeks’ gestation, who admits to cocaine abuse, complains of abdominal pain. She states that she has been experiencing moderate vaginal bleeding, no leakage of fluid per vagina, and has no history of trauma. On examination, her blood pressure is 150/90 mm Hg, and heart rate (HR) is 110 beats per minute (bpm). The fundus reveals tenderness, and a moderate amount of dark vaginal blood is noted in the vaginal vault. The ultrasound examination shows no placental abnormalities. The cervix is 1 cm dilated. The fetal heart tones are in the range of 160 to 170 bpm. The urine protein to creatinine ratio is 0.1 (normal < 0.3).
» What is the most likely diagnosis?
» What are complications that can occur due to this situation?
» What is the best management for this condition?
ANSWER TO CASE 11:
Placental Abruption
Summary: A 22-year-old G2P1 cocaine user at 35 weeks’ gestation complains of abdominal pain and moderate vaginal bleeding. On examination, her blood pressure is 150/ 90 mm Hg, and HR is 110 bpm. The fundus reveals tenderness. The ultrasound is normal. The fetal heart tones are in the range of 160 to 170 bpm.
- Most likely diagnosis: Placental abruption.
- Complications that can occur: Hemorrhage, fetal to maternal bleeding, coagulopathy, and preterm delivery.
- Best management for this condition: Delivery (at 35 weeks, the risks of abruption significantly outweigh the risks of prematurity).
ANALYSIS
See also answers to Case 10.
Objectives
- Understand that placental abruption and placenta previa are major causes of antepartum hemorrhage.
- Know the clinical presentation of abruptio placentae.
- Understand that coagulopathy is a complication of placental abruption.
Considerations
The patient complains of painful antepartum bleeding, which is consistent with placental abruption. Also, she has several risk factors for abruptio placentae, such as hypertension and cocaine use (Table 11– 1). The best treatment for pregnancies near term (>34 weeks) when abruption is strongly suspected is delivery. The natural history of placental abruption is extension of the separation, leading to complete shearing of the placenta from the uterus. As opposed to the diagnosis of placenta previa (see Case 10), ultrasound examination is a poor method of assessment for abruption. This is because the freshly developed blood clot behind the placenta has the same sonographic texture as the placenta itself. The urine protein to creatinine (P/ C) ratio of 0.1 is normal and consistent with gestational hypertension or hypertensive due to cocaine; however, a P/ C ratio ≥ 0.3 would be consistent with abnormal proteinuria and preeclampsia.
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Previous abruption in a prior pregnancy Cocaine use Short umbilical cord Trauma (direct or indirect) Uteroplacental insufficiency Submucosal leiomyomata Sudden uterine decompression (hydramnios) Cigarette smoking Preterm premature rupture of membranes
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APPROACH TO:
Suspected Placental Abruption
DEFINITIONS
CONCEALED ABRUPTION: When the bleeding occurs completely behind the placenta and no external bleeding is noted, this condition is less common than overt hemorrhage but more dangerous.
FETOMATERNAL HEMORRHAGE: Fetal blood that enters into the maternal circulation.
COUVELAIRE UTERUS: Bleeding into the myometrium of the uterus giving a discolored appearance to the uterine surface.
CLINICAL APPROACH
As compared to placenta previa (see Case 10), abruptio placentae is more dangerous and unpredictable. Furthermore, the diagnosis is much more difficult to establish. Ultrasound examination is not helpful in the majority of cases; a normal ultrasound examination does not rule out placental abruption. There is no one test that is diagnostic of placental abruption, but rather the clinical picture must be taken as a whole. Thus, a patient at risk for abruptio placentae (a hypertensive patient or one who has recently been involved in a motor vehicle accident), who complains of vaginal bleeding after 20 weeks’ gestation, must be suspected of having a placental abruption. Furthermore, the bleeding is often associated with uterine pain or hypertonus. The blood may seep into the uterine muscle and cause a reddish discoloration also known as the “Couvelaire uterus.” Uterine atony and postpartum hemorrhage after delivery may occur. Upon delivery, a blood clot adherent to the placenta is often seen. Another complication of abruption is coagulopathy. When the abruption is of sufficient severity to cause fetal death, coagulopathy is found in one-third or more of cases. The coagulopathy is secondary to hypofibrinogenemia, and clinically evident bleeding is usually not encountered unless the fibrinogen level is below 100 to 150 mg/ dL.
The diagnosis of placental abruption is difficult because the clinical presentation is variable. Although painful vaginal bleeding is the hallmark, preterm labor, stillbirth, and/or fetal heart rate abnormalities may also be seen. Ultrasound diagnosis is not sensitive. A concealed abruption can occur when blood is trapped behind the placenta, so that external hemorrhage is not seen. Serial hemoglobin levels, following the fundal height and assessment of the fetal heart rate pattern, are often helpful. As compared to placenta previa, fetal-to-maternal hemorrhage is more common with placental abruption, and some practitioners recommend testing for fetal erythrocytes from the maternal blood. One such test of acid elution methodology is called the Kleihauer–Betke test, which takes advantage of the different solubilities of maternal versus fetal hemoglobin.
The management of placental abruption is dependent on the fetal gestational age, fetal status, and the hemodynamic status of the mother. Delivery is the usual management! However, in a woman with a premature fetus (< 34 weeks) and a diagnosis of “chronic abruption,” expectant management may be exercised if the patient is stable with no active bleeding or signs of fetal compromise. Although there is no contraindication to vaginal delivery, cesarean section is often the chosen route of delivery for fetal indications. In cases of abruptions that are associated with fetal death and coagulopathy, the vaginal route is most often the safest for the mother. In the latter scenario, blood products and intravenous fluids are given to maintain the hematocrit above 25% to 30% and a urine output of at least 30 mL/ h. These women generally have very rapid labors. Many of these women will manifest hypertension or preeclampsia following volume replacement, and it may be necessary to start magnesium sulfate for eclampsia prophylaxis.
Future Pregnancies
There is a high recurrence risk of abruption, ranging from 5% to 10%. If a patient experiences abruptio placentae with two consecutive abruptions, the recurrence rate is as high as 25%. Smoking is the biggest modifiable risk factor (40-fold increased risk in smokers).
Women with prior abruption is an indication for early delivery for future pregnancies.
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CASE CORRELATION
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COMPREHENSION QUESTIONS
11.1 An 18-year-old pregnant woman is noted to have vaginal bleeding. She is bleeding from venipuncture sites, IV sites, and from her gums. Which of the following is the most likely underlying diagnosis?
A. Placental abruptionB. Placenta previaC. Gestational diabetesD. Multifetal gestationE. Gestational trophoblastic disease
11.2 A 32-year-old woman is seen in the obstetrical unit at the hospital. She is at 29 weeks’ gestation, with a chief complaint of significant vaginal bleeding. She had a stillbirth with her prior pregnancy due to placental abruption. The patient asks the physician about the accuracy of ultrasound in the diagnosis of abruption. Which of the following statements is most accurate?
A. Fetal ultrasound is more accurate in diagnosing placental abruption than placenta previa.B. Fetal ultrasound is quite sensitive in diagnosing placental abruption.C. Ultrasound is sensitive in diagnosing abruption that occurs in the lower aspect of the uterus.D. Fetal ultrasound is not sensitive in diagnosing placental abruption.
11.3 Which of the following is the most significant risk factor for abruptio placentae?
A. Prior cesarean deliveryB. Breech presentationC. TraumaD. Marijuana useE. Placenta accreta
11.4 A 35-year-old woman presents with bright red vaginal bleeding at 30 weeks’ gestation. Her urine drug screen is positive. Which of the following is most likely to be present in her drug screen?
A. MarijuanaB. AlcoholC. BarbituratesD. CocaineE. Benzodiazepines
11.5 A 28-year-old G1 P0 woman at 34 weeks’ gestation with chronic hypertension is admitted to the hospital for bright red bleeding per vagina. Her BP is 150/90, HR 90 and urine protein/creatinine ratio of 0.1. She is estimated to have lost 900 mL, and is actively bleeding. Her cervix is 2 cm dilated. The ultrasound shows a normal placenta. The fetal monitor reveals a hypertonic uterus and no fetal heart tones. Fetal demise is confirmed by ultrasound. Laboratories show hemoglobin of 9.5 g/ dL, platelet count of 90,000/ fL, and prothrombin time (PT) international normalized ratio (INR) of 2.0, and
PTT of 50 seconds. Which of the following is the best management for this patient?
A. Admission and careful observation in the ICUB. Induction of labor with plan for vaginal deliveryC. Partial exchange transfusionD. Urgent cesarean deliveryE. Intravenous terbutaline
ANSWERS
11.1 A. Placental abruption is a common cause of coagulopathy. Consumptive coagulopathy, also known as disseminated intravascular coagulation (DIC), involves the overactivation of the procoagulant pathways and can be a fatal complication of a placental abruption or other causes of hemorrhage. Placenta previa rarely results in consumptive coagulopathy, since there is usually a significantly less amount of bleeding involved in comparison with abruption. Gestational diabetes is more commonly associated with fetal macrosomia, and places the fetus at risk for shoulder dystocia at the time of delivery. Coagulopathy is not likely to be seen in gestational diabetes. A multifetal gestation puts a patient at a higher risk for a placenta previa due to the larger surface area required for the placenta(s), but as mentioned before, coagulopathy is not common in previa. The multifetal gestation itself does not increase maternal risk of coagulopathy. Gestational trophoblastic disease can be a benign or malignant cancer that develops in a woman’s womb and is commonly associated with a molar pregnancy. Bleeding from a site of metastasis may lead to hemorrhagic shock, but this is not very common, and therefore the chance of developing DIC from this complication is even less likely.
11.2 D. Sonography is accurate in identifying previa, but not sensitive in diagnosing placental abruption. An ultrasound examination is a poor method for assessment of abruption because the freshly developed blood clot behind the placenta has the same sonographic texture as the placenta itself. A high index of suspicion for abruption must be exercised when evaluating the clinical picture as a whole. An extra challenging situation exists in the setting of a concealed abruption, in which the bleeding occurs behind the placenta and no external bleeding is noted. This is extremely dangerous since a greater amount of time will most likely pass before the abruption is diagnosed.
11.3 C. Trauma is the most significant risk factor for abruption in comparison to the other answer choices. Extreme forces can shear the placenta away from the uterus in these situations. Marijuana, as opposed to cocaine, is not associated with abruption since it does not cause maternal hypertension and vasoconstriction like cocaine. A prior cesarean delivery may predispose a patient to placenta previa with an associated accreta in future pregnancies, but neither a prior cesarean delivery nor an accreta is a significant risk factor for abruption. The most significant fetal risk associated with breech presentation is cord prolapse, which can lead to significant oxygen deprivation to the fetus. Other risk factors for placental abruption include: uterine leiomyomata (especially submucosal type), hypertension, cocaine use, short umbilical cord, uteroplacental insufficiency, hydramnios, smoking, and preterm premature rupture of membranes (PPROM).
11.4 D. Cocaine use is strongly associated with the development of placental abruption due to its effect on the vasculature (vasospasm).
11.5 B. Fetal demise complicates 15% of clinically evident abruptions. When the abruption is severe enough to be associated with fetal demise, the patient will have clinical DIC in 25% of cases. Whereas, the management of placental abruption with a live fetus many times includes cesarean, with a fetal demise, the management focuses on vaginal delivery. This patient has findings consistent with DIC, and so clotting factors such as fresh frozen plasma, red blood cells, and also platelets should be transfused.
CLINICAL PEARLS
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» Painful antepartum bleeding should make one suspicious of placental abruption. » The diagnosis of abruptio placentae is a clinical one since it can present in many different ways. » The major risk factors for abruptio placentae are hypertension, trauma, and cocaine use, with hypertension being most common. » A concealed abruption may hide significant bleeding without external hemorrhage. » The most common cause of antepartum bleeding with coagulopathy is abruptio placentae. » Placental abruption may lead to fetal-to-maternal hemorrhage. » The risk of recurrence with abruption is significant, and may necessitate early delivery with subsequent pregnancies. |
REFERENCES
Cunningham FG, Leveno KJ, Bloom SL, et al. Obstetrical hemorrhage. In: Williams Obstetrics. 24th ed. New York, NY: McGraw-Hill; 2014:757-803.
Kim M, Hyashi RH, Gambone JC. Obstetrical hemorrhage and puerperal sepsis. In: H acker NF, Gambone JC, Hobel CJ, eds. Essentials of Obstetrics and Gynecology. 5th ed. Philadelphia, PA: Saunders; 2009:128-138.
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