Hypertensive disorders of pregnancy are one of the leading causes of maternal morbidity and mortality. It is a spectrum of disorders divided into the following categories: Gestational Hypertension (GHTN), Preeclampsia (with and without severe features), Eclampsia, and Chronic Hypertension with Superimposed Preeclampsia. The distinguishing feature between GHTN and preeclampsia is the lack of proteinuria with GHTN. Proteinuria is defined as a protein/creatinine ratio of 0.3 or greater, a 24-hour urine protein of 300mg/dl or greater, or a urinalysis protein value of 1+ or more if a quantitative option is unavailable. When the blood pressure is in the severe range, greater than or equal to 160 systolic or 110 diastolic, preeclampsia with severe features is diagnosed if one or more of the following are present:
Initial management includes antihypertensive medications which can be oral medications, if the values are in the mild range, or intravenous if the values are in the severe range. Common antihypertensive medications utilized include Labetalol, Hydralazine, and Nifedipine, which are compatible with breastfeeding. Seizure prophylaxis with magnesium sulfate is started when the blood pressure range is severe, or if the range is mild plus a severe sign/symptom.
Initial dose | Onset | Repeat if needed | Maximum dose | Side effects | |
Labetalol IV | 20mg | 1-2 minutes | Q10 minutes (40, 80) | 300mg | Avoid with asthma, bradycardia, heart block |
Hydralazine IV or IM | 5-10mg | 10-20 minutes | 10mg | 20mg | Hypotension, headache |
Nifedipine PO immediate release | 10-20mg | 5-10 minutes | Q20 min | 180mg | Tachycardia, headache |