â– LECTURE OVERVIEW: Preeclampsia is a multi-system, pregnancy-specific vasospastic disorder characterized by abnormal placental vascular remodeling.
â– BIOCHEMICAL PATHWAYS:
1. Spiral Artery Maladaptation: The primary defect is the failure of cytotrophoblasts to invade and remodel maternal spiral arteries. The arteries remain narrow, high-resistance vessels, leading to chronic placental ischemia.
2. Endothelial Injury: The ischemic placenta secretes anti-angiogenic factors (e.g., sFlt-1) that cause widespread maternal endothelial damage.
3. Systemic Vasospasm: Endothelial damage disrupts nitric oxide pathways, causing systemic vasospasm.
4. Glomerular Endotheliosis: Glomerular capillary endothelial swelling restricts filtration, presenting as proteinuria and elevated serum creatinine.
5. End-organ Vasoconstriction: Leads to cerebral edema (seizure risk), hepatic necrosis, and pulmonary edema.
â– RADIOGRAPHIC DIAGNOSTIC CRITERIA:
Imaging modalities (such as high-resolution CT, contrast-enhanced MRI, and point-of-care ultrasound) show characteristic density shifts, enhancement patterns, or structural deviations.
â– ACUTE TOXICOLOGICAL PROFILE:
High cumulative chemical exposure or accidental overdose triggers systemic receptor overload, cellular injury, and metabolic acidosis.
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🌟 Dynamic Clinical Key:
Preeclampsia is diagnosed by new-onset hypertension (BP >140/90 mmHg) presenting after 20 weeks gestation, accompanied by proteinuria (>300 mg/24h) or end-organ dysfunction. Severe cases can progress to HELLP syndrome (Hemolysis, Elevated Liver enzymes, Low Platelets). Treat with IV Magnesium Sulfate for seizure prophylaxis. Always correlate imaging signs with clinical presentation to avoid unnecessary surgical explorations of benign incidentalomas. Immediate administration of physiological charcoal or specific receptor antagonists is lifesaving.