3 OB 1- Hypertensive Disorders

Obstetrics 3.1

Dra. Padolina Sept. 4, 2014

Hypertensive Disorders OUTLINE I. Pregnancy Hypertension II. Classification of hypertension a. Gestational hypertension b. Preeclampsia-eclampsia syndrome c. Chronic Hypertension d. Chronic Hypertension with superimposed pre eclampsia III. Management of Pregnancy HPN IV. Antihypertensive Agents V. Preeclampsia without Severe Symptoms VI. Severe Preeclampsia VII. Chronic HPN before 38weeks AOG VIII. Research Recommendations REFERENCES 1. PPT/Lecture th 2. Williams 24 3. 2015a Trans 4. ACOG 2013 Guidelines for Hypertension in Pregnancy  

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PREGNANCY HYPERTENSION Hypertension is diagnosed empirically when blood pressure exceeds 2 140 mm Hg systolic or 90 mm Hg diastolic. In the past, it had been recommended that an incremental increase from midpregnancy values by 30 mm Hg systolic or 15 mm Hg diastolic pressure be used as diagnostic criteria, even when absolute values 2 were below 140/90 mm Hg. o These criteria are no longer recommended because evidence shows that such women are not likely to experience increased 2 adverse pregnancy outcomes Women who have a rise in pressure of 30 mm Hg systolic or 15 mm Hg 2 diastolic should be seen more frequently. Eclamptic seizures develop in some women whose blood pressures 2 have been below 140/90 mm Hg Edema is also no longer used as a diagnostic criterion because it is too 2 common in normal pregnancy to be discriminant.

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CLASSIFICATION OF HYPERTENSION Four types of hypertensive disease complicating pregnancy: o Gestational Hypertension o Preeclampsia-eclampsia o Chronic hypertension o Chronic hypertension with superimposed preeclampsia

Table 1. Comparison between gestational and chronic hypertension PROTEINURIA ONSET OF POST PARTUM HYPERTENSION GESTATIONAL absent >20 weeks age Resolves 20 weeks AOG, often near term o Systolic BP ≥ 140 mmHg or diastolic BP ≥ 90mmHg o Previously normotensive women o Resolves 1.1 mg/dL or doubling of baseline o Liver involvement  Serum transaminase levels twice normal o Cerebral symptoms  Headache, visual disturbances, convulsions o Pulmonary edema Diagnosis requires 2 determination at least 4-6 hours apart. If it is a severe case, shorten the period of observation to 4 hours.

ETIOLOGY & PATHOGENESIS  Natural history would dictate that the fetus would be at an advantage if there would be a direct increase of food and oxygen delivery from the 1 mother to the baby. o Thus during normal implantation, endovascular trophoblasts replace the vascular endothelial and muscular linings to enlarge 2 the diameter of the spiral arteries. (Fig. 1)  In some cases of preeclampsia, there may be incomplete trophoblastic invasion. With this, decidual vessels, but not myometrial vessels, become lined with endovascular trophoblasts. The deeper myometrial arterioles do not lose their endothelial lining and musculoelastic tissue, and their mean external diameter is only half that of corresponding 2 vessels in normal placentas. Page 1 of 5

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In preeclampsia, vasoconstriction of the spiral arteries (Fig. 2 yellow arrow) result in diminution of the nutrients and oxygen from the mother to the baby. Impact of which would be the syndrome of 1 preeclampsia o Diminished perfusion and a hypoxic environment eventually lead to release of placental debris or microparticles that incite a 2 systemic inflammatory response. o Antiangiogenic and metabolic factors and other inflammatory mediators are thought to provoke endothelial cell injury, which modify their nitric oxide production and interfere with 2 prostaglandin balance. Loss of maternal immune tolerance to paternally derived placental and fetal antigens is another theory cited to account for preeclampsia 2 syndrome. From a hereditary viewpoint, preeclampsia is a multifactorial, polygenic disorder. The hereditary predisposition for preeclampsia likely is the result of interactions of literally hundreds of inherited genes—both maternal and paternal—that control myriad enzymatic and metabolic 2 functions throughout every organ system. Any satisfactory theory concerning the etiology and pathogenesis of preeclampsia must account for the observation that gestational 2 hypertensive disorders are more likely to develop in women who: o Are exposed to chorionic villi for the first time
 o Are exposed to a superabundance of chorionic villi, as with twins or hydatidiform mole
 o Have preexisting renal or cardiovascular disease
 o Are genetically predisposed to hypertension developing during pregnancy.

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Table 2. Indicators of Severity of Preeclampsia CRITERIA NONSEVERE SEVERE Systolic BP ≤160mmHg ≥160mmHg Diastolic BP 5g o IUGR Preferred terminology: Preeclampsia with severe features or preeclampsia without severe features instead of using “mild” or 1 “severe” The differentiation between nonsevere and severe gestational hypertension or preeclampsia can be misleading because what might 2 be apparently mild disease may progress rapidly to severe disease.

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ECLAMPSIA Seizures or convulsions that cannot be attributed to other causes in a woman with preeclampsia New onset grand mal seizures in preeclampsia Premonitory events of severe headaches May also occur in the absence of warning signs and symptoms Differential diagnosis: AV malformation, ruptured aneurysm, idiopathic seizure disorder Case: A woman 22 weeks AOG in OPD, Systolic BP is 200mmHg, with a history of loss of consciousness in the ER. You later notice that the patient is having a seizure. If it cannot be attributed to any seizure disorders, suspect eclampsia. If not managed, patient can have stroke or may die Fetus may also die due to vasoconstriction of vessels CHRONIC HYPERTENSION Criteria: o BP ≥140/90 mmHg before pregnancy or diagnosed before 20 weeks gestation not attributable to gestational trophoblastic disease o Hypertension first diagnosed after 20 weeks gestation and persistent after 12 weeks postpartum CHRONIC HYPERTENSION WITH SUPERIMPOSED PRE ECLAMPSIA Proteinuria develops after 20 weeks Proteinuria present before 20 weeks with: o Sudden exacerbation of hypertension or increased anti-HPN drug dose o Sudden substantial, sustained increase in protein excretion Page 2 of 5

OBSTETRICS 3.1 

o Other severe features Over-diagnosis is preferred to increase surveillance

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MANAGEMENT  Delivery is the only effective treatment Table 3. Complications of Preeclampsia MATERNAL FETAL COMPLICATIONS COMPLICATIONS Abruptio placenta IUGR HELLP

NEONATAL COMPLICATIONS Respiratory Distress Syndrome Bronchopulmonary dysplasia Retinopathy of prematurity Hypoglycemia

Fetal death in utero

DIC Ischemic or hemorrhagic stroke Myocardial Infarction

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Necrotizing Enterocolitis (NEC) Neurodevelopmental problems/ Developmental delay

ANTEPARTUM MANAGEMENT Maternal Evaluation Laboratory Examination o CBC with platelet count o Serum Creatinine o LDH o Liver enzymes o 24 hour urine proteins Assessment of symptoms o Severe headache o Visual disturbances o Epigastric pain o Shortness of breath Fetal Evaluation o Daily kick count o Biometry o Amniotic fluid o Non stress test (NST) o Gestational Hypertension o Preeclampsia without severe features Biophysical Profile o Indirect way of looking into the fetal development HOSPITALIZATION Indicated for pregnant women with: o Gestational hypertension or preeclampsia without severe features  surveillance is continued in the hospital o New signs or symptoms of severe preeclampsia o Severe hypertension (160/110 mmHg or higher) o Evidence of fetal growth restriction o Increased liver enzymes or thrombocytopenia o Chronic hypertension with superimposed pre-eclampsia o Worsening disease or severe features o Concern for fetal well being ANTIHYPERTENSIVE AGENTS ANTIHYPERTENSIVE MEDICATIONS Antihypertensive therapy recommended in: o Preeclampsia with severe HPN - sustained systolic BP of ≥ 160 or diastolic BP of ≥ 110

Group 26 | Valera, Vallester, Velasco, Velasquez, Verdejo

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Chronic HPN: persistent systolic BP 160 or higher or diastolic BP at least 105 or higher Objectives in treatment of severe HPN: o No consensus in the management of HPN in pregnant patients if BP is NOT severely elevated. o Non pregnant adults:  Anti HPN med for BP >/= 140/90  Supported by large trials showing benefits in treatment Doppler Flow Analysis – helps determine when the optimum time is to deliver the baby Close monitoring of women with gestational hypertension or preeclampsia without severe features with assessment of: o Maternal symptoms o Fetal movement (daily) o BP monitoring o Platelet count and liver enzymes (weekly)

Table 4. Summary table for Pregnancy-related HPN requiring medications CLASSIFICATION OF HYPERTENSION Gestational preeclampsia Preeclampsia with severe hypertension Chronic Hypertension Chronic Hypertension

BP

MEDICATION No

QUALITY OR EVIDENCE Moderate

STRENGTH OF RECOMMENDATION Qualified