Too difficult to perform study procedures prior to giving blood pressure medication.

The purpose of the study is to compare the usefulness of Impedence Cardiography (ICG) directed therapy in treating severe range hypertension in pregnant women at term.

Research Protocol

Study Design: Randomized Control Trial This is a randomized control trial comparing the usefulness of impedance cardiography (ICG) directed therapy in treating severe range hypertension (systolic BP >160 OR diastolic BP >110) in patients greater than 20 weeks gestation. All patients in the study will receive standard of care medication within the suggested timeframe by the American College of Obstetrics and Gynecology (ACOG). All patients will receive a hemodynamic assessment prior to receiving and after receiving medications. The treatment patients will receive either labetalol or nifedipine therapy for hypertension based on their hemodynamic parameters. The control group will receive medication based on provider preference (which is the usual plan of care).

Study Population:

Patients presenting to Labor and Delivery at Cabell Huntington Hospital being treated for severe range blood pressures. Consent will be obtained prior to randomization to standard care or ICG directed care. Patient age range will be from age 15 to approximately 45.

Schedule of Assessment:

An interval assessment will be performed after 20 patients have been assessed. The goal is for a total enrollment of 100 patients, 50 to the ICG directed treatment group and 50 to the control group.

Study Procedures:

If a patient presents to Labor and Delivery at Cabell Huntington Hospital and consents to the study, she will be randomized to either the ICG directed therapy group or provider preference group. Patients from each group will receive a non-invasive hemodynamic assessment via the NICaS system. The NICaS system uses impedance cardiography which provides a reliable assessment of cardiovascular, respiratory, and fluid parameters. The vasodilator nifedipine will be initiated for increased systemic vascular resistance. Elevated cardiac output will be treated with beta blockade via IV labetalol. ACOG recommends either of these medications as first line therapy for elevated blood pressure, and offers no guidance on which medication should be used first. All patients who are being treated will receive the standard of care treatment, however the ICG group will receive therapy based on their hemodynamic parameters.

Study Analysis The control group will be compared to the ICG directed treatment group.

Inclusion Criteria:

• Patients presenting to Labor and Delivery at Cabell Huntington Hospital being treated for severe range blood pressure after 20 weeks gestation. Patients will be English speaking and range in ages from 15-45 years old. Patient's will be consented prior to randomization.

Exclusion Criteria:

• Patients presenting to Labor and Delivery at Cabell Huntington Hospital with normal range blood pressures, or those with elevated blood pressures who do not consent to the study, patients <20 weeks gestation, or patients with eclampsia.

Pregnant women