1、Hypertension in PregnancyLianne Beck,MDAssistant ProfessorEmory Family MedicineOBJECTIVESnKnow criteria for the diagnosis of chronic hypertension,gestational hypertension and preeclampsianList criteria for the diagnosis of severe preeclampsia/HELLP syndromenDiscuss current management considerationsI
2、ntroductionnMost common medical complication of pregnancyn6 to 8%of gestations in the US.nIn 2000,the National High Blood Pressure Education Program Working Group on High Blood Pressure in Pregnancy defined four categories of hypertension in pregnancy:qChronic hypertensionqGestational hypertensionqP
3、reeclampsiaqPreeclampsia superimposed on chronic hypertension Chronic Hypertension Defined1.BP measurement of 140/90 mm Hg or more on two occasions2.Before 20 weeks of gestation OR Persisting beyond 12 weeks postpartumChronic HypertensionnTreatment of mild to moderate chronic hypertension neither be
4、nefits the fetus nor prevents preeclampsia.nExcessively lowering blood pressure may result in decreased placental perfusion and adverse perinatal outcomes.nWhen BP is 150 to 180/100 to 110 mm Hg,pharmacologic treatment is needed to prevent maternal end-organ damage.Treatment of Chronic Hypertensionn
5、Methyldopa,labetalol,and nifedipine most common oral agents.nAVOID:ACEI and ARBs,atenolol,thiazide diureticsnWomen in active labor with uncontrolled severe chronic hypertension require treatment with intravenous labetalol or hydralazine.Gestational HypertensionnFormerly called PIH(Pregnancy Induced
6、HTN)nHTN without proteinuria occurring after 20 weeks gestation and returning to normal within 12 weeks after delivery.n50%of women diagnosed with gestational hypertension between 24 and 35 weeks develop preeclampsia.Older Criteria for Gestational HTN n30/15 increase in BP over baseline levelsnNo lo
7、nger appropriaten73%of patients will exceed 30 mm systolic and 57%will exceed 20 mm diastolicPreeclampsianNew onset hypertension with proteinuria after 20 weeks gestation.nResolves by 6 weeks postpartum.nCharacterized as mild or severe based on the degree of hypertension and proteinuria,and the pres
8、ence of symptoms resulting from involvement of the kidneys,brain,liver,and cardiovascular systemRisk FactorsFACTORRISK RATIORenal disease20:1Chronic hypertension10:1Antiphospholipid syndrome10:1Family history of PIH5:1Twin gestation4:1Nulliparity3:1Age 403:1Diabetes mellitus2:1African American1.5:1D
9、iagnostic Criteria for Preeclampsia1.SBP of 140 mm Hg or more or a DBP of 90 mm Hg or more on two occasions at least six hours apart after 20 weeks of gestation AND2.Proteinuria 300 mg in a 24-hour urine specimen or 1+or greater on urine dipstick testing of two random urine samples collected at leas
10、t four hours apart.nA random urine protein/creatinine ratio 0.21 indicates that significant proteinuria is unlikely with a NPV of 83%.nGeneralized edema(affecting the face and hands)is often present in patients with preeclampsia but is not a diagnostic criterion.HELLP SyndromenIs a variant of severe
11、 preeclampsianOccurs in up to 20%of pregnancies complicated by severe preeclampsia.nVariable clinical presentation;12 to 18%are normotensive and 13%do not have proteinuria.nAt diagnosis,30%of women are postpartum,18%are term,and 52%are preterm.HELLP SyndromenCommon presenting complaints are RUQ or e
12、pigastric pain,N/V,malaise or nonspecific symptoms suggesting an acute viral syndrome.nAny patient with these symptoms or signs of preeclampsia should be evaluated with CBC,platelet count,and liver enzymes.nWhen platelet count 105-110nSystolic BP 200nAvoid rapid reduction in BPnDo not attempt to nor
13、malize BPnGoal is DBP 105 not 30 mL per hour,limit to 100 mL per hour.nThe reason to treat is maternal,not fetalnMay require ICUCharacteristics of Severe HTNnCrises are associated with hypovolemianClinical assessment of hydration is inaccuratenUnprotected vascular beds are at risk,ie.,uterineKey Ste
14、ps Using Vasodilatorsn250-500 cc of fluid,IVnAvoid multiple doses in rapid successionnAllow time for drug to worknMaintain LLD positionnAvoid over treatmentAcute Medical TherapynHydralazinenLabetalolnNifedipinenNitroprussidenClonidineHydralazinenDose:5-10 mg every 20 minutesnOnset:10-20 minutesnDura
15、tion:3-8 hoursnSide effects:headache,flushing,tachycardia,lupus like symptomsnMechanism:peripheral vasodilatorLabetalolnDose:20 mg,then 40,then 80 every 20 minutes,for a total of 220mg nOnset:1-2 minutesnDuration:6-16 hoursnSide effects:hypotensionnMechanism:Alpha and Beta blockadeNifedipinenDose:10
16、 mg po,not sublingualnOnset:5-10 minutesnDuration:4-8 hoursnSide effects:chest pain,headache,tachycardianMechanism:CA channel blockadeClonidinenDose:1 mg ponOnset:10-20 minutesnDuration:4-6 hoursnSide effects:unpredictable,avoid rapid withdrawalnMechanism:Alpha agonist,works centrallyNitroprussidenD
17、ose:0.2 0.8 mg/min IVnOnset:1-2 minutesnDuration:3-5 minutesnSide effects:cyanide accumulation,hypotensionnMechanism:direct vasodilatorSeizure ProphylaxisnMagnesium sulfatenLoading dose of 4 to 6 g diluted in 100 mL of normal saline,given IV over 15 to 20 minutes,followed by a continuous infusion of
18、 1-2 g per hournMonitor urine output,RR and DTRsnWith renal dysfunction,may require a lower doseMagnesium SulfatenIs NOT a hypotensive agentnWorks as a centrally acting anticonvulsantnAlso blocks neuromuscular conductionnSerum levels:4-7 mg/dLnAdditional benefit of reducing the incidence of placenta
19、l abruptionToxicitynRespiratory rate 12nDTRs not detectablenAltered sensoriumnUrine output 25-30 cc/hournAntidote:10 ml of 10%solution of calcium gluconate 1 g IV over 2 minutes.EclampsianNew onset of seizures in a woman with pre-eclampsia.nPreceded by increasingly severe preeclampsia,or it may appe
20、ar unexpectedly in a patient with minimally elevated blood pressure and no proteinuria.nBlood pressure is only mildly elevated in 30-60%of women who develop eclampsia.nOccurs:Antepartum-53%,intrapartum-19%,or postpartum-28%Treatment of EclampsianProtecting the patient and her airwaynPlace patient on
21、 left side and suction to minimize the risk of aspirationnGive oxygen nAvoid insertion of airways and padded tongue bladesnIV accessnMag Sulfate 4-6 g IV bolus,if not effective,give another 2 gAlternate AnticonvulsantsnDiazepam 5-10 mg IVnSodium Amytal 100 mg IVnPentobarbital 125 mg IVnDilantin 500-
22、1000 mg IV infusionAfter the SeizurenAssess maternal labsnFetal well-beingnEffect deliverynTransport when indicatednNo need for immediate cesarean deliveryOther ComplicationsnPulmonary edemanOligurianPersistent hypertensionnDICPulmonary EdemanFluid overloadnReduced colloid osmotic pressurenOccurs mo
23、re commonly following delivery as colloid oncotic pressure drops further and fluid is mobilizedTreatment of Pulmonary EdemanAvoid over-hydrationnRestrict fluidsnLasix 10-20 mg IVnUsually no need for albumin or Hetastarch(Hespan)Oligurian25-30 cc per hour is acceptablenIf less,small fluid boluses of
24、250-500 cc as needednLasix is not necessarynPostpartum diuresis is commonnPersistent oliguria almost never requires a PA cathPersistent HypertensionnBP may remain elevated for several daysnDiastolic BP less than 100 do not require treatmentnBy definition,preeclampsia resolves by 6 weeksDisseminated
25、Intravascular CoagulopathynRarely occurs without abruptionnLow platelets is not DICnRequires replacement blood products and deliveryAnesthesia IssuesnContinuous lumbar epidural is preferred if platelets normalnNeed adequate pre-hydration of 1000 ccnLevel should always be advanced slowly to avoid low
26、 BPnAvoid spinal with severe diseaseSORT:KEY RECOMMENDATIONS FOR PRACTICEnIn women without end-organ damage,chronic hypertension in pregnancy does not require treatment unless the patients blood pressure is persistently greater than 150 to 180/100 to 110 mm Hg.CnCalcium supplementation decreases the
27、 incidence of hypertension and preeclampsia,respectively,among all women(NNT=11 and NNT=20),women at high risk of hypertensive disorders(NNT=2 and NNT=6),and women with low calcium intake(NNT=6 and NNT=13).AnLow-dose aspirin(75 to 81 mg daily)has small to moderate benefits for the prevention of pree
28、clampsia(NNT=72),preterm delivery(NNT=74),and fetal death(NNT=243).The benefit of aspirin is greatest(NNT=19)for prevention of preeclampsia in women at highest risk(previous severe preeclampsia,diabetes,chronic hypertension,renal disease,or autoimmune disease).BnFor women with mild preeclampsia,deli
29、very is generally not indicated until 37 to 38 weeks of gestation and should occur by 40 weeks.CnMagnesium sulfate is the treatment of choice for women with preeclampsia to prevent eclamptic seizures(NNT=100)and placental abruption(NNT=100).AnIntravenous labetalol or hydralazine may be used to treat
30、 severe hypertension in pregnancy because neither agent has demonstrated superior effectiveness.BnFor managing severe preeclampsia between 24 and 34 weeks of gestation,the data are insufficient to determine whether an interventionist approach(i.e.,induction or cesarean delivery 12 to 24 hours after
31、corticosteroid administration)is superior to expectant management.Expectant management,with close monitoring of the mother and fetus,reduces neonatal complications and stay in the newborn intensive care nursery.BnMagnesium sulfate is more effective than diazepam(Valium;NNT=8)or phenytoin(Dilantin;NN
32、T=8)in preventing recurrent eclamptic seizures.AQuiz1.Which one of the following statements about preeclampsia is correct?A.Magnesium sulfate is the treatment of choice to prevent eclamptic seizures.B.Diazepam(Valium)is more effective than magnesium sulfate in preventing recurrent eclamptic seizures
33、.C.Low-dose aspirin is beneficial for the prevention of preeclampsia in low-risk women.D.An interventionist approach is superior to expectant management for severe preeclampsia between 24 and 34 weeks of gestation.2.Which of the following agents is/are used to treat a 30-year-old woman(gravida 1,par
34、a 0)at 19 weeks of gestation who has had a blood pressure measurement of 160/115 mm Hg on two occasions during her current pregnancy?A.Methyldopa(Aldomet;brand no longer available in the United States).B.Nifedipine(Procardia).C.Labetalol.D.Lisinopril(Prinivil).3.Which of the following is/are part of
35、 the diagnostic criteria for severe preeclampsia?A.Blood pressure measurement 160 mm Hg systolic or 110 mm Hg diastolic on two occasions at least six hours apart.B.Blood pressure measurement 150 mm Hg systolic or 100 mm Hg diastolic on two occasions at least six hours apart.C.Proteinuria 3 g in a 24
36、-hour urine specimen.D.Proteinuria 5 g in a 24-hour urine specimen.ReferencesnLawrence L,Fontaine P.Hypertensive Disorders in Pregnancy.American Family Physician.July 1,2008.nWagner L.Diagnosis and Management of Preeclampsia.American Family Physician.December 15,2004.nACOG Committee on Obstetric Pra
37、ctice.ACOG practice bulletin.Diagnosis and management of preeclampsia and eclampsia.No.33,January 2002.American College of Obstetricians and Gynecologists.Obstet Gynecol 2002;99:159-67.nReport of the National High Blood Pressure Education Program Working Group on High Blood Pressure in Pregnancy.Am J Obstet Gynecol.2000;183(1):S1-S22.
