Hellp Syndrome

Basics

Description

  • HELLP syndrome:
    • Hemolysis
    • Elevated Liver Enzymes
    • Low Platelets
  • No universally accepted definition of HELLP
  • Continuum with severe preeclampsia as most patients will be hypertensive
  • Liver involvement is hallmark:
    • Other organs may be involved (eg, brain, kidneys, lungs)
  • Most maternal deaths occur with severe preeclampsia
  • Increased mortality rate is associated with hepatic hemorrhage or CNS or vascular insult to the cardiopulmonary or renal systems
  • Incidence: 0.2% of all pregnancies
  • 12–18% have normal BP
  • Occurs in 20% of pregnancies with severe preeclampsia or eclampsia
  • At diagnosis:
    • 52% preterm
    • 18% term
    • 32% postpartum

Risk Factors

Frequently white, multiparous, older

Pediatric Considerations

Infant mortality is greater in women with HELLP

Etiology

  • Unclear, but linked to the etiology of preeclampsia, which has 4 proposed etiologies:
    • Abnormal trophoblastic invasion of uterine vessels
    • Immune reaction to maternal, paternal, and fetal tissues
    • Maternal response to cardiovascular or inflammatory changes of pregnancy
    • Genetic factors
  • Proposed mechanism of HELLP:
    • Fetal–placental debris is released into maternal circulation, causing systemic inflammatory response and complement system dysregulation
    • Vascular constriction/congestion causes resistance to blood flow and HTN
    • Vasospasm probably damages vessels directly
    • Endothelial cell is damaged and interendothelial cell leaks are the result
  • Small-vessel leaks:
    • Platelets and fibrinogen get deposited in the subendothelium
    • Fibrin deposition develops in severe cases
  • Vascular changes and local tissue hypoxia lead to hemorrhage, necrosis, and end-organ damage

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