Hypertension in PregnancyHypertension in Pregnancy

Peter Bernstein, MD, MPHPeter Bernstein, MD, MPHAssociate Professor of Clinical Obstetrics & Gynecology Associate Professor of Clinical Obstetrics & Gynecology

and Women’s Healthand Women’s Health

Albert Einstein College of Medicine/Albert Einstein College of Medicine/

Montefiore Medical CenterMontefiore Medical Center

IntroductionIntroduction

Hypertension - one of the most common Hypertension - one of the most common medical complications of pregnancymedical complications of pregnancy

» Along with hemorrhage, complications of Along with hemorrhage, complications of hypertensive disorders are a leading cause of hypertensive disorders are a leading cause of maternal death (maternal death (~~15% of maternal deaths)15% of maternal deaths)

» It is also a major cause of perinatal morbidity and It is also a major cause of perinatal morbidity and mortality.mortality.

DefinitionsDefinitions

Chronic hypertensionChronic hypertension: : – A sustained BP > 140/90 that antecedes A sustained BP > 140/90 that antecedes

pregnancy or persists postpartum (beyond 6 pregnancy or persists postpartum (beyond 6 weeks). HTN that is present before the 20th weeks). HTN that is present before the 20th week of pregnancy may also be included as week of pregnancy may also be included as CHTN.CHTN.

DefinitionsDefinitions

PreeclampsiaPreeclampsia

– Hypertension that develops as a consequence of Hypertension that develops as a consequence of pregnancy and regresses postpartum and is pregnancy and regresses postpartum and is associated with proteinuria (associated with proteinuria (>> 300 mg./24 hrs.) 300 mg./24 hrs.)

– National High Blood Pressure Education Program Working National High Blood Pressure Education Program Working Group on High Blood Pressure in Pregnancy, 2000Group on High Blood Pressure in Pregnancy, 2000

Preeclampsia (continued)Preeclampsia (continued)

Preeclampsia is highly suspected in the absence of Preeclampsia is highly suspected in the absence of proteinuria if one of the following is present:proteinuria if one of the following is present:– headache, vision changes, abdominal pain, abnormal labsheadache, vision changes, abdominal pain, abnormal labs

Incidence:Incidence:– Nulliparous: 2-7%Nulliparous: 2-7%

– Twin gestations: 14%Twin gestations: 14%

– Previous preeclampsia: 18%Previous preeclampsia: 18%

Severe PreeclampsiaSevere Preeclampsia

BP 160/100mm Hg recorded on at least two BP 160/100mm Hg recorded on at least two occasions measured at least six hours apart.occasions measured at least six hours apart.

Proteinuria 5g/24 hours (3+ to 4+ on Proteinuria 5g/24 hours (3+ to 4+ on qualitative exams)qualitative exams)

Oliguria <500ml in 24 hours or 20 ml/hr.Oliguria <500ml in 24 hours or 20 ml/hr. Rise in serum Creatinine to over 1.2 mg/dL.Rise in serum Creatinine to over 1.2 mg/dL. Cerebral or visual changes.Cerebral or visual changes.

Severe Preeclampsia (cont.)Severe Preeclampsia (cont.)

– Pulmonary edema or cyanosis.Pulmonary edema or cyanosis.– Epigastric or right upper quadrant pain.Epigastric or right upper quadrant pain.– HELLP SyndromeHELLP Syndrome– Fetal Growth RestrictionFetal Growth Restriction– OligohydramniosOligohydramnios– Eclampsia: the presence of seizures in a patient Eclampsia: the presence of seizures in a patient

with PIH and not attributable to other causeswith PIH and not attributable to other causes

Severe Preeclampsia: HELLP Severe Preeclampsia: HELLP SyndromeSyndrome

A constellation of hematologic and hepatic A constellation of hematologic and hepatic manifestations in patients with PIH.manifestations in patients with PIH.– HHemolysis emolysis

» Microangiopathic hemolytic anemiaMicroangiopathic hemolytic anemia

– EElevated levated LLiver function testsiver function tests» Elevated liver enzymesElevated liver enzymes» Increased bilirubinIncreased bilirubin

– LLow ow PPlateletslatelets» Platelet count <100,000/mm3 Platelet count <100,000/mm3

DefinitionsDefinitions

Preeclampsia superimposed on chronic Preeclampsia superimposed on chronic hypertensionhypertension– In women with CHTN and no proteinuria prior to 20 In women with CHTN and no proteinuria prior to 20

weeks, new onset proteinuria (>300mg./24hrs.)weeks, new onset proteinuria (>300mg./24hrs.)

– In women with CHTN and proteinuria prior to 20 In women with CHTN and proteinuria prior to 20 weeks, sudden increase in proteinuria or BP, fall in weeks, sudden increase in proteinuria or BP, fall in platelets (<100k/mmplatelets (<100k/mm33), or elevation of LFTs.), or elevation of LFTs.

– Occurs in ~25% of pregnancies of women with CHTNOccurs in ~25% of pregnancies of women with CHTN

Gestational HypertensionGestational Hypertension

Hypertension detected at >20 weeks Hypertension detected at >20 weeks gestation in the absence of proteinuriagestation in the absence of proteinuria

IncidenceIncidence– Nulliparas: 6-12%Nulliparas: 6-12%– Multiparas: 2-4%Multiparas: 2-4%

Reclassified postpartum as:Reclassified postpartum as:– Transient Hypertension of Pregnancy if resolves by 12 Transient Hypertension of Pregnancy if resolves by 12

weeks postpartumweeks postpartum– Chronic Hypertension if does not resolveChronic Hypertension if does not resolve

Chronic HypertensionChronic Hypertension

Often seen in patients who have other Often seen in patients who have other medical complications: obesity, diabetes, medical complications: obesity, diabetes, hyperlipidemia, cigarette smoking.hyperlipidemia, cigarette smoking.– Essential HTN – majority will have normal Essential HTN – majority will have normal

pregnancies.pregnancies.– Secondary HTN – parenchymal renal disease, Secondary HTN – parenchymal renal disease,

pheochromocytoma, Cushing’s syndrome, pheochromocytoma, Cushing’s syndrome, hyperthyroidism, etc.hyperthyroidism, etc.

Chronic HypertensionChronic Hypertension

If end-organ disease is present (renal, If end-organ disease is present (renal, cardiac, cerebrovascular), there is an cardiac, cerebrovascular), there is an increased risk of morbidity and mortality.increased risk of morbidity and mortality.– Maternal – superimposed preeclampsia, Maternal – superimposed preeclampsia,

placental abruption, congestive heart failureplacental abruption, congestive heart failure– Fetal – intrauterine growth restriction, Fetal – intrauterine growth restriction,

prematurity and fetal deathprematurity and fetal death

Preconception Care of CHTNPreconception Care of CHTN

Review the medical history: diagnosis and Review the medical history: diagnosis and duration of hypertension, ongoing duration of hypertension, ongoing pharmacological treatment, known pharmacological treatment, known existence of organ damage or other existence of organ damage or other compounding illnesses.compounding illnesses.

Review obstetrical history.Review obstetrical history.

Preconception Care of CHTNPreconception Care of CHTN

Physical exam and laboratory evaluationPhysical exam and laboratory evaluation» Urine analysis, urine culture/sensitivity, 24 hour Urine analysis, urine culture/sensitivity, 24 hour

urine for total protein and creatinine clearanceurine for total protein and creatinine clearance

» CBCCBC

» Diabetes screeningDiabetes screening

» If the patient has severe hypertension, significant If the patient has severe hypertension, significant proteinuria or prior poor obstetric outcome more proteinuria or prior poor obstetric outcome more extensive tests may be offered.extensive tests may be offered.

Preconception Care of CHTNPreconception Care of CHTN

Optimize control with recommended medications.Optimize control with recommended medications.– MethyldopaMethyldopa (Aldomet): extensively studied in (Aldomet): extensively studied in

pregnant women, treatment of choice if needed. pregnant women, treatment of choice if needed. Central adrenergic inhibitor Central adrenergic inhibitor

– HydralazineHydralazine: potent vasodilator, which acts : potent vasodilator, which acts directly on vascular smooth muscle. directly on vascular smooth muscle.

– Calcium channel blockers Calcium channel blockers (Nifedipine): (Nifedipine): inhibits transmembrane calcium ion influx inhibits transmembrane calcium ion influx which causes vasodilation.which causes vasodilation.

AntihypertensivesAntihypertensives

– B-Adrenoreceptor blockers B-Adrenoreceptor blockers (e.g. atenolol, (e.g. atenolol, propranolol): possible fetal IUGR, neonatal propranolol): possible fetal IUGR, neonatal respiratory depression, bradycardia and respiratory depression, bradycardia and hypoglycemiahypoglycemia

– Angiotensin-converting enzyme inhibitorsAngiotensin-converting enzyme inhibitors: : not recommended for use in pregnancynot recommended for use in pregnancy

– Thiazides diureticsThiazides diuretics: not recommended for use : not recommended for use in pregnancy.in pregnancy.

Pregnancy management-HTNPregnancy management-HTN

First trimesterFirst trimester– Document EDCDocument EDC– Evaluate severity of hypertension and efficacy Evaluate severity of hypertension and efficacy

of medication if in use.of medication if in use.– Baseline CBC, urine analysis, urine culture, 24-Baseline CBC, urine analysis, urine culture, 24-

hour urine for total protein and creatinine hour urine for total protein and creatinine clearance, consider LFTs. Repeat each clearance, consider LFTs. Repeat each trimester as indicated.trimester as indicated.

Pregnancy Management-HTNPregnancy Management-HTN

Medication ManagementMedication Management– Antihypertensive medication usage for mild chronic Antihypertensive medication usage for mild chronic

hypertension in pregnancy is controversialhypertension in pregnancy is controversial

– Recommendations for therapyRecommendations for therapy» Continue medication if started prior to pregnancy and BP is Continue medication if started prior to pregnancy and BP is

controlled.controlled.

» Initiate antihypertensive medication if diastolic BP >100-110 mm Hg Initiate antihypertensive medication if diastolic BP >100-110 mm Hg or systolic BP >150-160 mm Hg.or systolic BP >150-160 mm Hg.

» If the BP increases rapidly and persists diastolic >110mm Hg or is If the BP increases rapidly and persists diastolic >110mm Hg or is associated with proteinura, deteriorating renal function or IUGR, associated with proteinura, deteriorating renal function or IUGR, delivery recommended.delivery recommended.

Pregnancy Management-HTNPregnancy Management-HTN

Antepartum surveillance recommended due Antepartum surveillance recommended due to increased mortality and morbidityto increased mortality and morbidity– Begin by 32 weeks EGA if there is renal Begin by 32 weeks EGA if there is renal

disease, IDDM, cardiac dysfunction or if disease, IDDM, cardiac dysfunction or if medication is used to manage the CHTN.medication is used to manage the CHTN.

» ?NST, BPP, AFI-UA Dopplers, fetal growth?NST, BPP, AFI-UA Dopplers, fetal growth

Pregnancy Management-HTNPregnancy Management-HTN

Superimposed preeclampsia is a concerning Superimposed preeclampsia is a concerning complication due to increased perinatal complication due to increased perinatal morbidity and mortality (Occurs in as many morbidity and mortality (Occurs in as many as 25% of CHTN pregnancies).as 25% of CHTN pregnancies).– Cannot rely on BP changes for diagnosis.Cannot rely on BP changes for diagnosis.– Follow new onset of proteinuria, Follow new onset of proteinuria,

thrombocytopenia, abnormal LFTs or thrombocytopenia, abnormal LFTs or generalized edema.generalized edema.

Pregnancy Management-HTN Pregnancy Management-HTN

Indications for delivery: Indications for delivery: – superimposed preeclampsiasuperimposed preeclampsia– IUGR at termIUGR at term– nonreassuring fetal testingnonreassuring fetal testing– consider if favorable cervix after 37 weeks consider if favorable cervix after 37 weeks

EGAEGA– completion of 39-40 weeks of pregnancy in an completion of 39-40 weeks of pregnancy in an

otherwise uncomplicated patientotherwise uncomplicated patient

Preeclampsia-DiagnosisPreeclampsia-Diagnosis

– Frequency: 2-10% of all pregnanciesFrequency: 2-10% of all pregnancies– Risk factorsRisk factors

» CHTNCHTN

» Chronic renal diseaseChronic renal disease

» Antiphospholipid syndromeAntiphospholipid syndrome

» DiabetesDiabetes

» Multiple gestationMultiple gestation

» NulliparityNulliparity

» Extremes of ageExtremes of age

PreeclampsiaPreeclampsia

Risk factors (cont.)Risk factors (cont.)– Hydatidiform moleHydatidiform mole– Previous history of preeclampsiaPrevious history of preeclampsia– Changing paternity in successive pregnanciesChanging paternity in successive pregnancies– Family history (inherited form, Family history (inherited form,

angiotensinogen gene T235)angiotensinogen gene T235)– FOB is the product of a preeclamptic pregnancyFOB is the product of a preeclamptic pregnancy

Preeclampsia-PresentationPreeclampsia-Presentation

Classic presentation: hypertension and Classic presentation: hypertension and proteinuriaproteinuria

BP elevation may be late.BP elevation may be late. Rarely develops before 20 weeks. If it Rarely develops before 20 weeks. If it

does, consider the diagnosis of does, consider the diagnosis of hydatidiform mole, antiphospholid hydatidiform mole, antiphospholid syndrome, or SLE.syndrome, or SLE.

PreeclampsiaPreeclampsia

Treatment: the only cure is delivery.Treatment: the only cure is delivery.» Differentiate between mild and severe preeclampsia.Differentiate between mild and severe preeclampsia.

» Antepartum fetal assessment for well-beingAntepartum fetal assessment for well-being• Daily fetal kick counts, NST twice a week, AFI weekly, Daily fetal kick counts, NST twice a week, AFI weekly,

growth scan q 2-3 weeksgrowth scan q 2-3 weeks

» Maternal BP monitoring, daily weight, serial Maternal BP monitoring, daily weight, serial laboratory studieslaboratory studies

» Consider glucocorticoid treatment for the fetus if Consider glucocorticoid treatment for the fetus if preterm.preterm.

Preeclampsia-ManagementPreeclampsia-Management

Induction indicationsInduction indications– Develops signs or symptoms of severe Develops signs or symptoms of severe

preeclampsiapreeclampsia– Nonreassuring fetal statusNonreassuring fetal status– TermTerm

Preeclampsia-MgSO4Preeclampsia-MgSO4

Use magnesium sulfate for seizure Use magnesium sulfate for seizure prophylaxis at time of labor or induction.prophylaxis at time of labor or induction.

•Bolus: 4-6g in 100ml of sterile water over 15-20 min.Bolus: 4-6g in 100ml of sterile water over 15-20 min.

•Rate: 2g/hourRate: 2g/hour

•Serum magnesium levels maintained between 4-7 mEq/LSerum magnesium levels maintained between 4-7 mEq/L

•Continue treatment for at least 24 hours after delivery.Continue treatment for at least 24 hours after delivery.

•Calcium gluconate, 1 g IV slowly over 2 minutes can be Calcium gluconate, 1 g IV slowly over 2 minutes can be administered for toxic levels of MgSO4 .administered for toxic levels of MgSO4 .

•Level 8-10 mEq/L – loss of patellar refluxLevel 8-10 mEq/L – loss of patellar reflux

•Level 12 mEq/L – respiratory arrestLevel 12 mEq/L – respiratory arrest

Severe PreeclampsiaSevere Preeclampsia

Due to increased risks for perinatal Due to increased risks for perinatal mortality and maternal morbidity and mortality and maternal morbidity and mortality, usually delivery is accomplished mortality, usually delivery is accomplished when the patient is diagnosed with severe when the patient is diagnosed with severe disease.disease.

Severe PreeclampsiaSevere Preeclampsia

If EGA < 34 weeks and the patient and If EGA < 34 weeks and the patient and fetus are stable, expectant management can fetus are stable, expectant management can be considered.be considered.– Maternal morbidity seen with observationMaternal morbidity seen with observation

• Abruptio placentaAbruptio placenta

• EclampsiaEclampsia

• CoagulopathyCoagulopathy

• Renal failureRenal failure

Severe PreeclampsiaSevere Preeclampsia

MgSO4 seizure prophylaxisMgSO4 seizure prophylaxis– Continue treatment for at least 24 hours and Continue treatment for at least 24 hours and

there is observed improvement or resolution of there is observed improvement or resolution of thrombocytopenia and liver and renal function.thrombocytopenia and liver and renal function.

– Antihypertensive medications if BP diastolic Antihypertensive medications if BP diastolic >110mm Hg or systolic >180mm Hg>110mm Hg or systolic >180mm Hg

» Hydralazine IV 5-10 mg bolus q 20 min.Hydralazine IV 5-10 mg bolus q 20 min.

» Labetalol 20 mg IV q 10-20 min. (max 300 mg)Labetalol 20 mg IV q 10-20 min. (max 300 mg)

Preeclampsia-PreventionPreeclampsia-Prevention

– The use of low-dose aspirin to prevent The use of low-dose aspirin to prevent preeclampsia in nulliparous women has been preeclampsia in nulliparous women has been studied. The incidence of preeclampsia was studied. The incidence of preeclampsia was reduced, but no improvement in fetal or reduced, but no improvement in fetal or neonatal morbidity or mortality was seen.neonatal morbidity or mortality was seen.

– Nutritional supplementation – calcium, Nutritional supplementation – calcium, magnesium, zinc: adequate outcome data magnesium, zinc: adequate outcome data showing improvement has not been showing improvement has not been documented.documented.

Preeclampsia-RecurrencePreeclampsia-Recurrence

Patients are at increased risk for recurrent Patients are at increased risk for recurrent PIH in future pregnancies. The risk is PIH in future pregnancies. The risk is greater based on the EGA and severity of greater based on the EGA and severity of the first pregnancy with PIH/preeclampsia.the first pregnancy with PIH/preeclampsia.

There is an association between PIH and a There is an association between PIH and a later diagnosis of CHTN.later diagnosis of CHTN.

EclampsiaEclampsia

The Most Common Cause of Peripartum The Most Common Cause of Peripartum SeizuresSeizures– Can’t predict who will have seizuresCan’t predict who will have seizures

– Can’t rely on BP elevations. Approx. 20% of the Can’t rely on BP elevations. Approx. 20% of the patients who have eclampsia has normal BP.patients who have eclampsia has normal BP.

– Can’t rely on proteinuria. 10% of patients will have a Can’t rely on proteinuria. 10% of patients will have a seizure before overt proteinuria.seizure before overt proteinuria.

– Neurologic tests are only useful for patients with Neurologic tests are only useful for patients with atypical features. (Late postpartum seizures, atypical features. (Late postpartum seizures, persistent abnormalities in the mental status, focal persistent abnormalities in the mental status, focal neurological deficits)neurological deficits)

Eclampsia-TreatmentEclampsia-Treatment

– Control of convulsions: magnesium sulfateControl of convulsions: magnesium sulfate– Correction of hypoxia and acidosisCorrection of hypoxia and acidosis– Blood pressure controlBlood pressure control– HydralazineHydralazine– Magnesium sulfate is not administered to control Magnesium sulfate is not administered to control

BP.BP.– Delivery after control of convulsions. Vaginal Delivery after control of convulsions. Vaginal

delivery is still attempted if not otherwise delivery is still attempted if not otherwise contraindicated.contraindicated.

HELLP Syndrome HELLP Syndrome

Liver Involvement in PreeclampsiaLiver Involvement in Preeclampsia» DiagnosisDiagnosis

– Differential diagnosis: acute fatty liver of pregnancy Differential diagnosis: acute fatty liver of pregnancy (AFLP), hepatitis, thrombotic thrombocytopenic (AFLP), hepatitis, thrombotic thrombocytopenic purpura (TTP) and hemolytic uremic syndrome, purpura (TTP) and hemolytic uremic syndrome, gallbladder disease, appendicitis, gastroenteritis.gallbladder disease, appendicitis, gastroenteritis.

– In some populations, this variation of PIH can occur In some populations, this variation of PIH can occur in 20% of women with severe preeclampsia.in 20% of women with severe preeclampsia.

– Very high morbidity: placental abruption, acute renal Very high morbidity: placental abruption, acute renal failure, pulmonary edema, subcapsular liver failure, pulmonary edema, subcapsular liver hematoma.hematoma.

HELLP SyndromeHELLP Syndrome

TreatmentTreatment» The only cure is delivery.The only cure is delivery.» Consider platelet transfusion for platelet count Consider platelet transfusion for platelet count

50,000/mm3 if undelivered and surgical hemostasis will 50,000/mm3 if undelivered and surgical hemostasis will be needed.be needed.

» Use of IV Dexamethasone may lessen severity and Use of IV Dexamethasone may lessen severity and speed resolutionspeed resolution

Recurrence of HELLP in future pregnanciesRecurrence of HELLP in future pregnancies» 5% in patients with preexisting CHTN5% in patients with preexisting CHTN» 3% in patient with normotensive patients3% in patient with normotensive patients

ConclusionConclusion

Hypertensive disorders of pregnancy are Hypertensive disorders of pregnancy are frequently seen. Recognizing the frequently seen. Recognizing the diagnostic features and understanding the diagnostic features and understanding the management of these illnesses will help to management of these illnesses will help to decrease the associated increased maternal decrease the associated increased maternal and neonatal morbidity and mortality.and neonatal morbidity and mortality.