Hypertension in Hypertension in PregnancyPregnancy

District I ACOG Medical District I ACOG Medical Student Education Module Student Education Module

20112011

Etiology & DefinitionEtiology & Definition

Complicates 10-20% of pregnanciesComplicates 10-20% of pregnancies

Elevation of BP Elevation of BP ≥140 mmHg systolic ≥140 mmHg systolic and/or ≥90 mmHg diastolic, on two and/or ≥90 mmHg diastolic, on two occasions at least 6 hours apart.occasions at least 6 hours apart.

CategoriesCategories

Chronic HypertensionChronic Hypertension Gestational HypertensionGestational Hypertension PreeclampsiaPreeclampsia Preeclampsia superimposed on Preeclampsia superimposed on

Chronic HypertensionChronic Hypertension

Chronic HypertensionChronic Hypertension

““Preexisting Hypertension”Preexisting Hypertension” DefinitionDefinition

Systolic pressure Systolic pressure ≥ 140 mmHg, diastolic ≥ 140 mmHg, diastolic pressure ≥90 mmHg, or both. pressure ≥90 mmHg, or both.

Presents before 20Presents before 20thth week of pregnancy or week of pregnancy or persists longer then 12 weeks postpartum.persists longer then 12 weeks postpartum.

CausesCauses Primary = “Essential Hypertension”Primary = “Essential Hypertension” Secondary = Result of other medical Secondary = Result of other medical

condition (ie: renal disease)condition (ie: renal disease)

Prenatal Care for Prenatal Care for Chronic HypertensivesChronic Hypertensives

Electrocardiogram should be obtained in women with long-standing hypertension.

Baseline laboratory tests Urinalysis, urine culture, and serum creatinine,

glucose, and electrolytes Tests will rule out renal disease, and identify

comorbidities such as diabetes mellitus. Women with proteinuria on a urine dipstick

should have a quantitative test for urine protein.

Treatment for Chronic Treatment for Chronic HypertensionHypertension

Avoid treatment in women with uncomplicated mild essential HTN as blood pressure may decrease as pregnancy progresses.

May taper or discontinue meds for women with blood pressures less than 120/80 in 1st trimester.

Reinstitute or initiate therapy for persistent diastolic pressures >95 mmHg, systolic pressures >150 mmHg, or signs of hypertensive end-organ damage.

Medication choices = Oral methyldopa and labetalol.

PreeclampsiaPreeclampsia Definition = New onset of hypertension Definition = New onset of hypertension and and

proteinuria after 20 weeks gestation.proteinuria after 20 weeks gestation. Systolic blood pressure Systolic blood pressure ≥≥140 mmHg 140 mmHg OROR diastolic diastolic

blood pressure blood pressure ≥≥90 mmHg90 mmHg Proteinuria of 0.3 g or greater in a 24-hour urine Proteinuria of 0.3 g or greater in a 24-hour urine

specimen specimen Preeclampsia before 20 weeks, think MOLAR Preeclampsia before 20 weeks, think MOLAR

PREGNANCY!PREGNANCY! CategoriesCategories

Mild PreeclampsiaMild Preeclampsia Severe PreeclampsiaSevere Preeclampsia

EclampsiaEclampsia Occurrence of generalized convulsion and/or coma in Occurrence of generalized convulsion and/or coma in

the setting of preeclampsia, with no other the setting of preeclampsia, with no other neurological condition.neurological condition.

PreeclampsiaPreeclampsia Severe Preeclampsia must have one of the Severe Preeclampsia must have one of the

following:following: Symptoms of central nervous system dysfunction = Symptoms of central nervous system dysfunction =

Blurred vision, scotomata, altered mental status, severe Blurred vision, scotomata, altered mental status, severe headacheheadache

Symptoms of liver capsule distention = Right upper Symptoms of liver capsule distention = Right upper quadrant or epigastric painquadrant or epigastric pain

Nausea, vomitingNausea, vomiting Hepatocellular injury = Serum transaminase Hepatocellular injury = Serum transaminase

concentration at least twice normalconcentration at least twice normal Systolic blood pressure Systolic blood pressure ≥≥160 mm Hg or diastolic 160 mm Hg or diastolic ≥≥110 110

mm Hg on two occasions at least six hours apartmm Hg on two occasions at least six hours apart Thrombocytopenia = <100,000 platelets per cubic Thrombocytopenia = <100,000 platelets per cubic

milimetermilimeter Proteinuria = 5 or more grams in 24 hoursProteinuria = 5 or more grams in 24 hours Oliguria = <500 mL in 24 hoursOliguria = <500 mL in 24 hours Severe fetal growth restrictionSevere fetal growth restriction Pulmonary edema or cyanosisPulmonary edema or cyanosis Cerebrovascular accidentCerebrovascular accident

Preeclampsia superimposed Preeclampsia superimposed on Chronic Hypertensionon Chronic Hypertension

Affects 10-25% of patients with chronic Affects 10-25% of patients with chronic HTNHTN

Preexisting Hypertension with the Preexisting Hypertension with the following additional signs/symptoms: following additional signs/symptoms: New onset proteinuriaNew onset proteinuria Hypertension and proteinuria beginning Hypertension and proteinuria beginning

prior to 20 weeks of gestation.prior to 20 weeks of gestation. A sudden increase in blood pressure.A sudden increase in blood pressure. Thrombocytopenia.Thrombocytopenia. Elevated aminotransferases.Elevated aminotransferases.

Treatment of Treatment of PreeclampsiaPreeclampsia

Definitive Treatment = Definitive Treatment = DeliveryDelivery Major indication for antihypertensive

therapy is prevention of stroke. Diastolic pressure ≥105-110 mmHg or

systolic pressure ≥160 mmHg Choice of drug therapy:Choice of drug therapy:

Acute – IV labetalol, IV hydralazine, SR Acute – IV labetalol, IV hydralazine, SR Nifedipine Nifedipine

Long-term – Oral methyldopa or labetalolLong-term – Oral methyldopa or labetalol

Gestational HypertensionGestational Hypertension

Mild hypertension Mild hypertension without without proteinuria or proteinuria or other signs of preeclampsia. other signs of preeclampsia.

Develops in late pregnancy, after 20 weeks Develops in late pregnancy, after 20 weeks gestation. gestation.

Resolves by 12 weeks postpartum.Resolves by 12 weeks postpartum. Can progress onto preeclampsia.Can progress onto preeclampsia.

Often when hypertension develops <30 weeks Often when hypertension develops <30 weeks gestation.gestation.

Indications for and choice of antihypertensive therapy are the same as for women with preeclampsia..

Risk Factors for Risk Factors for Hypertension in PregnancyHypertension in Pregnancy

NulliparityNulliparity Preeclampsia in a previous pregnancyPreeclampsia in a previous pregnancy Age >40 years or <18 yearsAge >40 years or <18 years Family history of pregnancy-induced hypertensionFamily history of pregnancy-induced hypertension Chronic hypertensionChronic hypertension Chronic renal diseaseChronic renal disease Antiphospholipid antibody syndrome or inherited Antiphospholipid antibody syndrome or inherited

thrombophiliathrombophilia Vascular or connective tissue diseaseVascular or connective tissue disease Diabetes mellitus (pregestational and gestational)Diabetes mellitus (pregestational and gestational) Multifetal gestationMultifetal gestation High body mass indexHigh body mass index Male partner whose previous partner had preeclampsiaMale partner whose previous partner had preeclampsia Hydrops fetalisHydrops fetalis Unexplained fetal growth restrictionUnexplained fetal growth restriction

Evaluation of Hypertension Evaluation of Hypertension in Pregnancyin Pregnancy

HistoryHistory ID and ComplaintID and Complaint HPI (S/S of HPI (S/S of

Preeclampsia)Preeclampsia) Past Medical Hx, Past Past Medical Hx, Past

Family Hx Family Hx Past Obstetrical Hx, Past Obstetrical Hx,

Past Gyne HxPast Gyne Hx Social HxSocial Hx Medications, AllergiesMedications, Allergies Prenatal serology, blood Prenatal serology, blood

workwork Assess for Hypertension Assess for Hypertension

in Pregnancy risk in Pregnancy risk factorsfactors

PhysicalPhysical VitalsVitals HEENT = Vision HEENT = Vision CardiovascularCardiovascular RespiratoryRespiratory Abdominal = Abdominal =

Epigastric pain, RUQ Epigastric pain, RUQ painpain

Neuromuscular and Neuromuscular and Extremities = Reflex, Extremities = Reflex, Clonus, EdemaClonus, Edema

Fetus = Leopold’s, Fetus = Leopold’s, FM, NSTFM, NST

Evaluation of Hypertension Evaluation of Hypertension in Pregnancyin Pregnancy

Laboratory TestsLaboratory Tests CBC (Hgb, Plts)CBC (Hgb, Plts) Renal Function (Cr, UA, Albumin)Renal Function (Cr, UA, Albumin) Liver Function (AST, ALT, ALP, LD)Liver Function (AST, ALT, ALP, LD) Coagulation (PT, PTT, INR, Fibrinogen)Coagulation (PT, PTT, INR, Fibrinogen) Urine Protein (Dipstick, 24 hour) Urine Protein (Dipstick, 24 hour)

Management of Management of Hypertension in PregnancyHypertension in Pregnancy

Depends on severity of hypertension Depends on severity of hypertension and gestational age!!!!and gestational age!!!!

Observational ManagementObservational Management Restricted activityRestricted activity Close Maternal and Fetal MonitoringClose Maternal and Fetal Monitoring

BP MonitoringBP Monitoring S/S of preeclampsiaS/S of preeclampsia Fetal growth and well being (NST, and U/S)Fetal growth and well being (NST, and U/S)

Routine weekly or biweekly blood workRoutine weekly or biweekly blood work

Management of Management of Hypertension in PregnancyHypertension in Pregnancy

Medical ManagementMedical Management Acute Therapy = IV Labetalol, IV Acute Therapy = IV Labetalol, IV

Hydralazine, SR Nifedipine Hydralazine, SR Nifedipine Expectant Therapy = Oral Labetalol, Expectant Therapy = Oral Labetalol,

Methyldopa, NifedipineMethyldopa, Nifedipine Eclampsia prevention = MgSO4Eclampsia prevention = MgSO4

Contraindicated antihypertensive Contraindicated antihypertensive drugsdrugs

ACE inhibitorsACE inhibitors Angiotensin receptor antagonistsAngiotensin receptor antagonists

Management of Management of Hypertension in PregnancyHypertension in Pregnancy

Proceed with DeliveryProceed with Delivery Vaginal Delivery VS Cesarean SectionVaginal Delivery VS Cesarean Section Depends on severity of hypertension!Depends on severity of hypertension! May need to administer antenatal May need to administer antenatal

corticosteroids depending on gestation!corticosteroids depending on gestation!

Only cure is Only cure is DELIVERY!!!DELIVERY!!!