What are the causes of neonatal subgaleal hemorrhage?

Causes of Neonatal Subgaleal Hemorrhage

The primary cause of neonatal subgaleal hemorrhage is instrumental delivery, particularly vacuum extraction, which significantly increases the risk of this potentially fatal condition. 1

Definition and Pathophysiology

Subgaleal hemorrhage occurs when blood accumulates between the epicranial aponeurosis and the periosteum of the skull due to rupture of the emissary veins that connect the dural sinuses and scalp veins. This creates a potentially dangerous space where significant blood loss can occur, leading to hypovolemia and shock.

Major Causes

Traumatic Causes

• Instrumental delivery
  • Vacuum extraction (primary risk factor) 1
  • Forceps delivery (less common than vacuum) 2
  • Failed vacuum extraction attempts (particularly high risk) 2
  • Prolonged or forceful vacuum suction 2

Maternal Risk Factors

• Primiparous women 2
• Severe dystocia 2
• Occiput lateral or posterior head presentations 2

Congenital Bleeding Disorders

• Hemophilia A - can present as spontaneous subgaleal hemorrhage without traumatic delivery 3
• Neonatal alloimmune thrombocytopenia - can cause subgaleal hemorrhage even in cesarean deliveries 4

Other Contributing Factors

• Coagulopathies 2
• Thrombocytopenia 4

Clinical Presentation

Subgaleal hemorrhage typically presents within the first 24 hours of life with:

• Fluctuant swelling of the head that crosses suture lines
• Pallor and lethargy
• Signs of hypovolemia and shock in severe cases
• Progressive anemia 3

Risk Stratification

Recent research has developed machine learning models to predict the risk of subgaleal hemorrhage based on first-stage labor data, which could help identify high-risk cases before vacuum extraction is attempted. These models showed a 2-4 fold increase in risk identification for high-risk groups 5.

Prevention and Management

• Limit vacuum extraction in high-risk situations 2
• Avoid repeated, forceful, or prolonged vacuum suction 2
• Consider alternative delivery methods for high-risk cases
• For neonates with congenital bleeding disorders:
  • Early diagnosis is crucial
  • Prompt treatment of hypovolemia and anemia
  • Factor replacement for hemophilia cases 3
  • Platelet transfusion for thrombocytopenia 4

Diagnostic Evaluation

For neonates with subgaleal hemorrhage without obvious risk factors (such as instrumental delivery):

• Evaluate for congenital bleeding disorders
• Consider hemophilia testing, especially in male infants 3
• Check platelet count to rule out neonatal alloimmune thrombocytopenia 4

Key Considerations

• Subgaleal hemorrhage is potentially fatal if not recognized and treated promptly
• The condition may be the first presentation of an underlying bleeding disorder
• Even cesarean section deliveries can be associated with subgaleal hemorrhage in the presence of bleeding disorders 4
• Successful outcomes require early diagnosis, careful monitoring, and prompt treatment 3