The underlying causes of chest pain in pregnancy are similar to those of nonpregnant women. Some disorders, such as aortic dissection and cardiomyopathy, may be associated with pregnancy. Treat pregnant women with acute myocardial infarction with aspirin, heparin, and percutaneous intervention rather than thrombolytics. Treat congestive heart failure and pulmonary edema with standard modalities except for sodium nitroprusside. It should be avoided as it can cause thiocyanate and cyanide accumulation in the fetus.
Chronic hypertension is defined as blood pressure at or above 140/90 mmHg prior to pregnancy, prior to 20 weeks’ gestation or lasting more than 12 weeks after delivery. These patients are at risk for abruption, preeclampsia, low birth weight, cesarean delivery, premature birth, and fetal demise.
Gestational hypertension is defined as blood pressure at or above 140/90 mmHg after 20 weeks or in the immediate postpartum period but without proteinuria.
Hypertension in pregnancy is defined as a systolic blood pressure ≥140 mmHg or diastolic ≥90 mmHg on two occasions at least 4 hours apart in a woman who was normotensive prior to 20 weeks’ gestation.
Preeclampsia is characterized by hypertension, greater than 140/90 mmHg, on two occasions at least 4 hours apart and proteinuria ≥300 mg in 24 hours in patients at 20 weeks’ gestation until 4 to 6 weeks after delivery. In the absence of proteinuria, thrombocytopenia with platelet count less than 100,000, elevation of liver enzymes twice normal, new renal insufficiency with a creatinine of 1.1 or a doubling of serum creatinine, pulmonary edema, or new-onset mental status disturbances or visual disturbances can be used to make the diagnosis of preeclampsia. Edema may or may not be present. Symptoms of severe preeclampsia reflect end-organ involvement and may include headache, visual disturbances, mental status changes, edema, oliguria, dyspnea due to pulmonary edema, and abdominal pain. Blood pressure in severe preeclampsia is typically elevated to 160/110 mmHg or more.
HELLP syndrome is probably a clinical variant of preeclampsia. It is characterized by hemolysis, elevated liver enzymes, and low platelets. Patients usually complain of abdominal pain, especially epigastric and right upper quadrant pain. Because the blood pressure is not always elevated, HELLP syndrome should be considered in the evaluation of all pregnant women greater than 20 weeks’ gestation with abdominal pain.
Eclampsia is preeclampsia with seizures.
Diagnosis and Differential
Preeclampsia is a clinical diagnosis. The following laboratory abnormalities may be seen in severe preeclampsia: anemia, thrombocytopenia, elevated creatinine, elevated liver enzymes, elevated LDH. The HELLP variant is diagnosed by laboratory tests: schistocytes on peripheral smear, platelet count lower than 150,000/mL, and elevated aspartate aminotransferase and alanine aminotransferase levels. The differential diagnosis of preeclampsia includes worsening of preexisting hypertension, transient hypertension, renal disease, fatty liver disease of pregnancy, and coagulation disorders. Focused ultrasonography or a CT scan of the pelvis and abdomen should be done if concerns for subcapsular hematoma exist as this has a high risk of maternal and fetal mortality if ruptured.
Emergency Department Care and Disposition
Treat severe preeclampsia and eclampsia with magnesium sulfate loading dose of 4 to 6 g IV over 20 minutes, followed by a maintenance infusion of 1 to 2 g/h to prevent seizure. Monitor serum magnesium levels and reflexes.
Treat severe hypertension, greater than 160/110 mm Hg, with labetalol 20 mg IV initial bolus, followed by repeat boluses of 40 to 80 mg, if needed, to a maximum of 300 mg for blood pressure control or hydralazine 5.0 mg IV initially, followed by 5 to 10 mg every 10 minutes.
Consult an obstetrician emergently for severe preeclampsia or eclampsia.
Hospitalize all patients with a sustained systolic blood pressure ≥140 mmHg or diastolic ≥90 mmHg plus any symptoms of preeclampsia.
Definitive treatment requires delivery of the fetus.
In patients with mild preeclampsia, outpatient management may be appropriate after consultation with an obstetrician. Arrangements must be made for frequent laboratory evaluation and close fetal surveillance.