A postoperative subdural hematoma is an accumulation of blood between the dura mater and arachnoid membrane that occurs after cranial surgery. It may be ipsilateral, contralateral, or bilateral, and can be acute or delayed in onset.

• Tearing of bridging veins during brain shift or retraction
• Intraoperative injury to cortical veins
• Coagulopathy (e.g., thrombocytopenia, anticoagulants, NSAIDs)
• Overdrainage of CSF (ventricular or lumbar)
• Sudden changes in intracranial pressure
• Brain atrophy (elderly patients more vulnerable)

• Less common than epidural hematoma but more frequent in elderly or anticoagulated patients
• May present acutely (within 48 h) or subacutely/delayed (days to weeks)

• Delayed awakening or deterioration of consciousness
• Progressive headache
• Hemiparesis or focal deficits
• Dysphasia, seizures
• Neurological worsening after initial improvement

• CT scan: crescent-shaped, hypodense/isodense or hyperdense subdural collection
• MRI: helpful in iso/hypodense cases or delayed diagnosis
• May show midline shift or compression of ventricles

• Epidural hematoma
• Postoperative infarct
• Hygroma
• Tension pneumocephalus

• Surgical evacuation if:
  1. Mass effect present
  2. Neurological symptoms worsen
  3. Thickness >10 mm or midline shift >5 mm
• Techniques:
  1. Burr-hole drainage
  2. Craniotomy in organized or solid hematomas
• Reversal of anticoagulation or platelet transfusion if needed
• Intensive monitoring (neuro ICU)

• Depends on timing of diagnosis and neurological status at treatment
• Good prognosis with early recognition and intervention
• Delayed or missed SDH may lead to irreversible injury

• Careful hemostasis and gentle brain retraction
• Controlled CSF drainage during and after surgery
• Avoid sudden intracranial pressure shifts
• Close monitoring in high-risk patients (elderly, anticoagulated)
• Early postoperative CT scan if symptoms or risk factors present