This patient mostly likely has amniotic fluid embolism syndrome (AFES), a rare but catastrophic complication during pregnancy or the immediate postpartum period.  Risk factors include advanced maternal age, grand multiparity, placental abruption, and an operative or cesarean delivery.

AFES occurs when amniotic fluid enters the maternal circulation through areas of disrupted maternofetal connections, such as endocervical veins, areas of uterine trauma (eg, hysterotomy), and initiates a widespread inflammatory response leading to the following:

• Hypoxemic respiratory failure due to significant pulmonary vasoconstriction from proinflammatory mediators and physical obstruction from amniotic fluid debris, which lead to severe hypoxia.  The resultant profound hypoxia can cause a coma or seizure, as seen in this patient.

• Obstructive shock due to increasing pulmonary arterial resistance, which leads to subsequent right ventricular heart failure and decreased left-sided cardiac output.  This is often followed immediately by left ventricular failure and resultant pulmonary edema (ie, crackles) and cardiovascular collapse (eg, hypotension).

• Disseminated intravascular coagulopathy (DIC), causing profuse bleeding from multiple sites (eg, uterine, intravenous line sites)

AFES is diagnosed clinically and requires prompt recognition as complete cardiovascular collapse rapidly ensues.  Treatment requires intubation with mechanical ventilation to correct the hypoxemia, vasopressors to support blood pressure, and massive transfusion to correct the DIC.  Despite early and aggressive intervention, few patients survive, and often with permanent and severe neurologic sequelae.

(Choice A)  Carboprost is a prostaglandin that stimulates uterine contractions to treat postpartum hemorrhage from uterine atony.  This patient's bleeding from her intravenous line sites suggests an etiology other than uterine atony.  Carboprost does not treat DIC and may worsen this patient's respiratory status due to bronchospasm.

(Choice B)  Furosemide can treat pulmonary edema and improve hypoxia due to fluid overload.  Although pulmonary edema does commonly occur with AFES, this patient's respiratory failure requires initial intubation and mechanical ventilation before further treatment with furosemide.

(Choice C)  Heparin anticoagulation is generally indicated for pulmonary thromboembolism, which can cause acute cardiopulmonary failure.  Heparin should not be administered in patients with significant bleeding or signs of platelet dysfunction.

(Choice E)  Magnesium sulfate can be used to treat eclampsia, which can cause seizures in pregnancy; however, patients usually have hypertension.  This patient's significant hypotension makes eclampsia less likely.

Educational objective:
Amniotic fluid embolism syndrome typically presents with a rapid onset of respiratory failure, obstructive shock with severe hypotension, and disseminated intravascular coagulopathy during labor or the immediate postpartum period.  The diagnosis is made clinically, and management is supportive.