Diagnosis

Subdural hematoma

Collection of blood between the dura and arachnoid mater:

  • Acute (< 24 hours)

  • Subacute (24 hours-2 weeks)

  • Chronic (> 2 weeks old)

Also known as: SDH, Subdural hemorrhage

Etiology

Cause [svd][psb][idp]

Pathophysiology [sno]

  1. Dura mater - a protective layer around the brain tissue

  2. Arachnoid mater is under the dura mater with many bridging veins between the layers

  3. Acceleration-deceleration force --> bridging veins may rupture --> subdural hematoma

  4. Larger space between the layers --> stretches bridging veins --> prone to rupture:

    • Young, growing brain

    • Aging brain (because of contraction)

  5. A minor subdural bleeding may increase the distance and trigger new bleeding foci

  6. Acute --> subacute --> chronic (development of encapsulating membrane)

Risk factors [idp]

Epidemiology

Incidence per 100.000 [sno][v5d][mwu][wbr]

Epidemiology chart for Incidence

Symptoms & findings

Symptoms

Amnesia, Anisocoria, Anopsia, Anorexia, Apathy, Aphasia, Ataxia, Bradycardia, Cheyne-Stokes respiration, Coma, Confusion, Cushing's triad, Decreased consciousness, Deviated gaze, Diplopia, Dizziness, Drowsiness, Dysarthria, Headache, Irregular respiration, Lethargy, Myalgia, Nausea, Paresis, Paresthesia, Seizure, Unconsciousness, Vomiting, Weakness, Wide pulse pressure

Clinical findings

Decreased Blood Urea Nitrogen, Decreased Uric Acid, Elevated Intracranial Pressure, Hyponatremia, Hyposmolality

Anamneses

Trauma

Localized findings

Pain
Radiates
Caput
Onset
Hyperacute (seconds)Acute (minutes)Subacute (hours)Gradual (days)
Pattern
Constant
Severity
Moderate (4-7)Severe (8-10)

Approach

Treatment

  1. Initial treatment: [sno]

    • Airway

    • Breathing

    • Circulation

  2. Conservative non-surgical management: [sno]

    • The hematoma does not cause impingement on the brain or the brain stem

  3. If increasing hematoma or signs of increased intracranial pressure: [sno][wbr]

    • Sedation

    • Neuromuscular blockade when appropriate

    • Moderate hyperventilation to a Pc02 (32 to 36)

    • Adequate oxygenation to maintain Sp02 greater than 95%

    • Head elevation

    • Avoidance of hyperthermia

    • Hypertonic saline or mannitol --> decrease the intracranial pressure

    • Surgery:

      • Burr hole craniostomy + subdural drain

      • Craniotomy

Differential diagnoses

Arteriovenous malformation, Brain abscess, Brain tumor, Cerebral aneurysm, Dementia, Encephalitis, Epidural hematoma, Hydrocephalus, Intracerebral hemorrhage, Meningitis, Multiple sclerosis, Stroke, Subarachnoid hemorrhage, Syndrome of inappropriate antidiuretic hormone secretion, Toxoplasmosis, Transient ischemic attack

References

[1] Mehta V, Harward SC, Sankey EW, Nayar G, Codd PJ. Evidence based diagnosis and management of chronic subdural hematoma: A review of the literature. J Clin Neurosci. 2018 Apr;50:7-15.

[2] Fomchenko EI, Gilmore EJ, Matouk CC, Gerrard JL, Sheth KN. Management of Subdural Hematomas: Part I. Medical Management of Subdural Hematomas. Curr Treat Options Neurol. 2018 Jun 23;20(8):28.

[3] https://emedicine.medscape.com/article/1137207

[4] Pierre L, Kondamudi NP. Subdural Hematoma. [Updated 2023 Aug 12]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK532970/

[5] Rauhala M, Luoto TM, Huhtala H, Iverson GL, Niskakangas T, Öhman J, Helén P. The incidence of chronic subdural hematomas from 1990 to 2015 in a defined Finnish population. J Neurosurg. 2019 Mar 22;132(4):1147-1157.

[6] Bartek J Jr, Sjåvik K, Ståhl F, Kristiansson H, Solheim O, Gulati S, Sagberg LM, Förander P, Jakola AS. Surgery for chronic subdural hematoma in nonagenarians: A Scandinavian population-based multicenter study. Acta Neurol Scand. 2017 Nov;136(5):516-520.

[7] El Rahal A, Beck J, Ahlborn P, Bernasconi C, Marbacher S, Wanderer S, Burkhardt JK, Daniel RT, Ferrari A, Hausmann O, Kamenova M, Kothbauer K, Lutz K, Mariani L, Alfieri A, Schöni D, Schucht P, Raabe A, Regli L, Kuhlen D, Seule M, Soleman J, Starnoni D, Zaldivar J, Zweifel C, Schaller K, Fung C. Incidence, therapy, and outcome in the management of chronic subdural hematoma in Switzerland: a population-based multicenter cohort study. Front Neurol. 2023 Sep 14;14:1206996.

[8] Stubbs DJ, Vivian ME, Davies BM, Ercole A, Burnstein R, Joannides AJ. Incidence of chronic subdural haematoma: a single-centre exploration of the effects of an ageing population with a review of the literature. Acta Neurochir (Wien). 2021 Sep;163(9):2629-2637.

Scroll to top