Response to Anti-hypertensives in Pregnant and Postpartum Patients

Phase 4

Completed

Brief Summary: In this study, the investigators will evaluate the blood pressure response to nifedipine and labetalol in pregnant and postpartum patients, who present with hypertensive disease in pregnancy with severe range blood pressure defined as greater than 160/110. These anti-hypertensives are first line therapy for management of severe range blood pressures in pregnancy and postpartum by the American Congress of Obstetricians and Gynecologist (ACOG). In addition at the Mount Sinai West site, the investigators will also analyze the ADRB1 and similar genes involved in beta blockade, genes involved in calcium channel blockade and other genes implicated in blood pressure response among pregnant and postpartum patients receiving labetalol and nifedipine. This analysis will be used to determine if a pharmacogenetic association exists between variant alleles in these receptors in the pregnant and postpartum population.

Detailed Description: Hypertensive disease in pregnancy is a major cause of maternal morbidity and mortality. This condition is responsible for about 12% of the maternal deaths in the United States.

Currently, if pregnant patients present with severe hypertension they are either given IV labetalol, IV hydralazine of nifedipine based on individual provider preference. There are few studies in the literature comparing oral nifedipine and IV labetalol with mixed data showing either they are equally effective or a faster time to achieving target blood pressure for patients who received nifedipine.

In this study, the investigators will evaluate if there is a difference in time to achieve goal blood pressure in pregnant and postpartum patients who are treated with nifedipine and labetalol for severe range blood pressures defined as greater than 160/110. These anti-hypertensives are first line therapy for management of severe range blood pressures in pregnancy and postpartum by the American Congress of Obstetricians and Gynecologist (ACOG).

Recruitment & Eligibility

Inclusion Criteria

pregnant patients from 20 weeks to up to 6 weeks postpartum
between the ages of 18-55.
persistent severe range blood pressures (2 readings or more within 15 minutes) of either 160mmHg systolic or 110mmHg diastolic.

Exclusion Criteria

multiple gestation
patients with non-reassuring fetal heart rate (category 3)
patients with abruptio placenta
patients with renal impairment
history of heart failure
history of cardiac arrhythmia
use of anti-hypertensive medications in the past 24 hours
patients with allergies or medical contraindications to labetalol or nifedipine.

Arm && Interventions

Group	Intervention	Description
Oral nifedipine	Nifedipine	Oral medication 10mg and 20mg
Intravenous labetalol	Labetalol	intravenous medication 20mg, 40mg, 80 mg

Primary Outcome Measures

Name	Time	Method
Time to Achieve Non Severe Range Blood Pressure	Ten minute intervals from the time of the first severe range blood pressure, up to 1 hour	Time to achieve goal blood pressure, that is, non severe range blood pressures after medication received.
Number of Participants to Achieve Non Severe Range Blood Pressure	up to 1 hour	Number of participants by ethnicity to achieve goal blood pressure, that is, non severe range blood pressures after medication received.

Secondary Outcome Measures

Name	Time	Method
Number of Participants With Medication Side Effects	assessed 10 minutes to 1 hour after medication is given	Number of participants with side effect profile to assess the rate of side effects from IV labetalol and oral nifedipine
Frequency of Genetic Variants of Genes	up to 1 year	the frequency of variant alleles in different receptors involved in the response to labetalol and nifedipine administration in the pregnant and postpartum population.