Hypertension Flashcards
A 16 yo G1P0 at 35 weeks GA attends a prenatal visit and is found to have a BP of 158/100 mm Hg. She otherwise feels well. A repeat BP is 152/104 mm Hg the next day.
hypertensive disorders of pregnancy: why they matter
-among the MC medical complications of pregnancy
-affects up to 10% of all pregnancies
-responsible for up to 16% of all maternal deaths
-incidence has increased over 25% in the past 20 years
why HTN disorders of pregnancy matter
-maternal mortality rates have increased in the US over the past 4 years
-17.4/100,000 live births in 2018 to 23.8/100,000 in 2020
-HTN disorders ranks THIRD among direct causes of maternal deaths
-MCC of maternal death is sepsis -> followed by hemorrhage
long term sequelae of HTN disorders of pregnancy for parturients
-pts with a history of pre-eclampsia have twice the risk of cardiovascular disease in later years than patients who were normotensive
-Patients with a history of pre-eclampsia who delivered at <34 weeks gestational age have an eight to ninefold risk of cardiovascular disease
-Not due to the pre-eclampsia itself, but rather due to common risk factors between cardiovascular disease and pre-eclampsia
-These patients should have annual evaluation and targeted lab studies with their primary care clinician
fetal sequelae of HTN disorders
-Prematurity
-Intrauterine growth restriction (IUGR)
-Fetal weight at or <10%ile (by estimated fetal weight) at current gestational age
-We will discuss IUGR later in this course
-assoc with an increased relative risk of death (RR 2.77)
-all of the sequelae listed below are due to prematurity:
-intraventricular hemorrhage (RR, 1.19)
-respiratory distress syndrome (RR, 1.27)
-necrotizing enterocolitis (RR, 1.27)
hypertensive disorders of pregnancy
-chronic HTN
-gestational HTN
-pre-eclampsia
-superimposed pre-eclampsia
-pre-eclampsia with severe features
-hemolysis, elevated liver function tests, low platelets (HELLP) syndrome
-eclampsia
-postpartum HTN
-we will define all the disorders, but will focus on:
-Pre-eclampsia
-Pre-eclampsia with severe features
-Eclampsia
-HELLP syndrome
chronic HTN
-presents prior to conception or to 20 weeks of gestation
-BP measured at 140/90 or higher on 2 separate occasions at least 4hrs apart
-assoc with:
-Superimposed pre-eclampsia
-Cesarean section
-Preterm delivery
-Low birth weight
-Neonatal ICU (NICU) admission
gestational hypertension
-Affects 5-10% of all pregnancies
-Differs from chronic hypertension in that it occurs at or after 20 weeks GA
-BP of 140/90 mm Hg or higher on 2 separate occasions at least 4 hours apart !WITHOUT other conditions that define pre-eclampsia! in pts who were previously normotensive
-Requires close monitoring of BP
pre-eclampsia
-Occurs at or after 20 weeks GA
-BP of 140/90 mm Hg or higher on 2 separate occasions at least 4 hours apart after 20 weeks gestation in patients who were previously normotensive, !with at least one of the following!:
-New onset proteinuria
-Thrombocytopenia
-Elevated transaminases
-Renal insufficiency
-Pulmonary edema
-Cerebral symptoms
-Persistent headache
-Scotomata
-Blurred vision
risk factors for pre-eclampsia
-nulliparity
-Multifetal gestation
-Prior history of pre-eclampsia
-Chronic HTN
-DM (pregestational or gestational)
-History of thrombophilia
-lupus
-pregnancy obesity
-hx of antiphospholipid antibody syndrome
-AMA
-renal ds
-hx of assisted reproductive technology (IVF)
-hx of obstructive sleep apnea
pathophysiology of pre-eclampsia
-We subdivide this disorder in those that present before 34 weeks EGA and those that occur after 34 weeks EGA
-Early-onset pre-eclampsia (<34wks) tends to be associated with placental abnormality
-Cytotrophoblasts normally migrate into the spiral arteries
-This increases blood flow, but in these patients the cytotrophoblasts invade the spiral arteries, narrowing them and leading to placental ischemia, hypoxia, and pre-eclampsia
-There is also an association between placenta accreta spectrum and retained placenta with pre-eclampsia
-late onset pre-eclampsia tends to be assoc with obesity and primiparity
-other factors include: IVF, donor oocyte, autologous frozen embryo transfers
lab results that define pre-eclampsia
-proteinuria:
-May be defined as any of the following:
->300 mg proteinuria in 24 hour urine collection
-Protein/creatinine ratio > 0.3
-Creatinine >1 mg/dL
-Urine dipstick of 1+ protein or higher
-Use this method only if no other method is available
-thrombocytopenia:
-Platelet count <100,000/mcl
-transaminase abnormalities:
-Elevated transaminases > 2x upper limit of normal with or w/o RUQ or epigastric pain
signs and symptoms of pre-eclampsia
-CNS:
-headache (usually severe)
-Blurred vision
-Scotomata- both eyes
-pulmonary edema
pre-eclampsia with severe features
-Systolic BP of ≥160 mm Hg and/or diastolic BP of ≥110 mm Hg on 2 separate occasions 4 hours apart while at rest !with at least one of the following!:
-New onset proteinuria
-Thrombocytopenia
-Elevated transaminases
-Persistent severe RUQ or epigastric tenderness
-Renal insufficiency
-Pulmonary edema
-Cerebral symptoms- Persistent headache or visual changes
-NO ONE IS WAITING 4 HOURS WITH THIS
hemolysis, elevated LFTs, and low platelets (HELLP) syndrome
-affects <1% of all pregnancies
-assoc with pre-eclampsia, but up to 20% of all pts do not have a hx of HTN or of pre-eclampsia at dx:
-However, 20% of patients with pre-eclampsia will develop HELLP
-All patients with HELLP should be presumed to have pre-eclampsia
S&S of HELLP syndrome
-Epigastric or RUQ pain
-Headache
-Visual changes
-Nausea and vomiting
-!!However, the syndrome is defined by presence of thrombocytopenia, hemolysis, and elevated transaminases!!
lab results that define HELLP syndrome
-elevated transaminases >=70
-elevated LDH >= 600
-platelets <=100 x 10^6
management of HELLP syndrome
-supportive care
-at < 24 wks- consider recommendation for termination
-at <32 wks: magnesium sulfate for fetal neuroprotection (cerebral palsy)
-<34 wks: antenatal steroids for fetal lung maturation
-delivery is curative- individualize timing of delivery
superimposed pre-eclampsia
-pts with known chronic hypertension in first half of pregnancy !who then develop proteinuria after 20 weeks of gestation, or!:
-Develop significantly uncontrolled hypertension after 20 weeks
-Develop other signs of pre-eclampsia, including:
-Elevated transaminases
-Thrombocytopenia
-Renal insufficiency
-Epigastric or right upper quadrant pain
-CNS symptoms, such as headache, blurred vision, or scotomata
-About 26% of patients with chronic hypertension will develop superimposed pre-eclampsia
eclampsia
-New onset tonic-clonic, focal, or multifocal seizures in a pre-eclamptic patient
-Often preceded by severe frontal or occipital headache, visual changes, photophobia, and altered mental status
-Headaches are due to cerebral edema and hypertensive encephalopathy
-Up to 25% of patients do not present with hypertension or proteinuria prior to onset of eclampsia
-Manage with magnesium sulfate 6 gm IV over 15-20 minutes
-Maternal mortality rate is as high as 7%
-Perinatal mortality is as high as almost 12%
postpartum HTN
-!!Unfortunately, hypertensive disorders of pregnancy can present after delivery
-May present as gestational hypertension OR pre-eclampsia -> Usually present by 6 weeks postpartum
-BP may be labile in the puerperium and beyond, up to 6 months postpartum
tx of HTN disorders of pregnancy
-DELIVERY
-!!But other things may have to be done first to manage the disease before proceeding to delivery!
-Manage hypertension
-Possible induction of labor- depending on dilation, wks, etc.
-Prophylaxis to reduce risk of eclampsia
-platelets need to be 50,000 for OR (for any surgery)
evaluation of the antepartum pt with suspected or known HTN disorders of pregnancy
-hx:
-Inquire about
-Headache, blurred vision, scotomata, dyspnea, epigastric or RUQ pain
-Vaginal bleeding, painful contractions, fetal movement
-lab data:
-CBC
-Transaminases
-BUN/creatinine
-24 hour urine or elevated protein/creatinine ratio
-Coagulation profile
-Liver function tests
-Lactate dehydrogenase
-Fetal surveillance: (“dont worry about this we will do it next week”)
-Nonstress test (external fetal heart monitoring)
-Ultrasound:
-Measurement of estimated fetal weight (normal: >10%ile for gestational age)
-Amniotic fluid index (normal: 5-25 cm)
-Biophysical profile (normal: 8-10/10) -> Evaluates fetus via real time sonography for: fetal breathing movements, amniotic fluid index, gross fetal movements, fetal tone, and nonstress test
when to deliver for the parturient with HTN disorders of pregnancy: indications
-Any of the following:
-Uncontrolled severe range BPs not responsive to treatment
-Persistent headache with no response to treatment
-Right upper quadrant or epigastric pain with no response to pain Rx
-Visual or motor deficit
-CVA
-MI
-Liver and/or renal disturbances
-Pulmonary edema
-Seizure
-Suspected abruptio placentae
