Hypertension in pregnancy

Def 🍭

Etiopathogenesis

Hypertension disorders in preg 🗼

Hypertensive disorders

Delta hypertension: Sudden ⬆ in mABP – some woman will deve Eclamptic seizure or HELLP syndrome while still normoactive

Risk factors 🍇

Etiology

Placental implantation with Abnormal trophoblastic invasion of uterine vessels (not entering myometrium in Preeclampsia pt) ➭ ⬇ blood flow ➭ Ischemia

Immunological maladaptive tolerance between Maternal, Paternal (placental), and fetal tissues

Maternal adaptation to CVS or Inflammatory changes of normal preg

Genetic factors including Inherited predisposing genes and epigenetic influences

Pathogenesis 🍇

PathoPSO

BP ≥ 140/90 mmHg or

⬆ SBP 30 mmHg or DBP 15 mmHg over the pre- or early pregnancy lvl

🍰Gestational HT

🍰Preeclampsia-Eclampsia

🍰Chronic HTN

🍰Chronic HTN with superimposed preeclampsia

Sustained SBP ≥ 140 mmHg or DBP ≥ 90 mmHg
(Inc in BP must measured ≥ 2 seperate occasions ≥ 6 hours or more apart)

BP returns to baseline by 12 wks postpartum ➪ Dx Transient hypertension of preg

💛HTN GA after 20 wks + No proteinuria or Absence of other findings suggest preeclampsia

Preg specific HTN with Multisystem involvement

💛1. New onset HTN with New onset proteinuria* in GA after 20 wks

Significant proteinuria*

24hr urine protein ≥ 300 mg

UPCR ≥ 0.3

Urine dipstick 1+

💛2. New onset HTN without proteinuria with New onset of any of the following

Thrombocytopenia (plt < 100,000/microL)

Renal insufficiency (Serum Cr ≥ 1.1 mg/dL or Doubling Serum Cr conc. in absence of other renal ds)

Impaired LFT (x2 of normal conc of Liver transaminases – AST, ALT)

Pulmonary edema

Cerebral or Visual symptoms

Degrees

Mild (nonsevere): SBP ≥ 140 mmHg and/or DBP ≥ 90 mmHg AND Proteinuria ≥ 300 mg on 24hr urine collection or dipstick +1 on single sample

Severe🍇 : same as Mild plus any of the item listed

SBP ≥ 160 mmHg or DBP ≥ 110 mmHg

24 hr collection of Urine protein excretion ≥ 5 g

Thrombocytopenia

Hepatic dysfunction (Elevated liver transaminases or Epigastric pain)

Renal compromise (Oliguria, or Elevated serum Cr ≥ 1.1 in nonrenal ds women)

Pulmonary edema

Neurologic disturbances (Visual changes, Headache, Seizures, Coma)

Placental abruption, Fetal growth restriction, or Oligohydramnios

HELLP syndrome - variant of preeclampsia with poor prognosis
(Hemolysis, Elevated LFT, Low plt) 🍇

Eclampsia: Preeclampsia + Convulsions

Often preceded by premonitory event – Severe headache & hyperreflexia

  • 25% hv eclamptic seizures before labor
  • 50% hv eclamptic seizures during labor
  • 25% hv eclamptic seizures after delivery*

HTN present predate conception or before GA 20 wks

HTN that persists beyond 12 wks postpartum

Complications: 15% of gestational HT can deve into Chronic HT, 25% risk of deve superimposed preeclampsia or eclampsia

💛 New onset proteinuria in a woman with Chronic HT and no proteinuria prior GA 20 wks

💛 Women with proteinuria before GA 20 wks who more likely in the following seven scenarios 🎑

Sudden exacerb. of HT or Need to escalate anti-HT drug dose esp when prev. well controlled with these meds

Sudden manifestations of S&S -- ⬆ abn Liver enzymes

Plt < 100,000/microliters

manifest symptoms (RUQ pain and severe headaches)

deve Pulmonary congestion or edema

deve Renal insufficiency (Serum Cr doubling or increasing ≥ 1.1 mg/dL in women w/o other renal ds)

Sudden, substantial ad sustained increases in protein excretion

Young & nulliparous women

Advanced maternal age

Race and ethnicity (genetic predisposition)

Socioeconomic

Seasonal influences

Obesity

Metabolic syndrome

Multifetal gestation

Hyperhomocysteinemia

Theory of Preeclampsia pathogenesis: 2 stage disorder

Stage I Poor placentation:
Incomplete trophoblastic invasion of spiral arterioles ➭ ⬇ uteroplacental blood flow

Stage II Inflammation:
Ischemic placenta induces Widespread endothelial cell damage and Maternal systemic inflammatory response (such conditions include CVS, Renal ds, DM, obesity, Immunological disorders or Hereditary influences)

Normal preg: ⬇ immune respone ➭ preserve preg

Preeclampsia: Immune response dysfunc

Immunological factors

preeclampsia is multifactorial, polygenic disorder

60% concordance in monozygotic, female twin pairs

22 - 47% twins

20 - 40% daughter of preeclamptic mothers

11 - 37% sisters of preeclamptic women

7 things 🍇

CVS changes

Hematologic changes

HELLP syndrome

Coagulation change* (as ⬆ coagulopathy)

Endocrine changes

Renal changes

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