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An Overview of Head Injury Management. Eldad J. Hadar, M.D. Department of Neurosurgery. Checklist. Definitions Glasgow Coma Scale Intracranial Pressure Mechanisms of brain injury Evaluation of head injury Management of head injury Operative Nonoperative. Head Injury Guidelines.
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An Overview of Head Injury Management Eldad J. Hadar, M.D. Department of Neurosurgery
Checklist • Definitions • Glasgow Coma Scale • Intracranial Pressure • Mechanisms of brain injury • Evaluation of head injury • Management of head injury • Operative • Nonoperative
Head Injury Guidelines • 1995 – 1st edition • 2000 – 2nd edition • 2007 – 3rd edition • Level I – Accepted principles reflecting high degree of clinical certainty • Level II – Strategies reflecting moderate degree of clinical certainty • Level III – Degree of clinical certainty not established
Checklist Definitions • Glasgow Coma Scale • Intracranial Pressure • Mechanisms of brain injury • Evaluation of head injury • Management of head injury • Operative • Nonoperative
Glasgow Coma Scale (GCS) • Introduced by Teasdale and Jennett in 1974 • Consists of 3 clinical signs that have • Prognostic significance • Good reproducibility between observers • Scale range 3-15 • GCS < 8 has generally become accepted as representing coma / severe head injury
Intracranial Pressure (ICP) CPP = MAP – ICP • Normal CPP > 50 mm Hg • Autoregulatory mechanisms maintain CBF at CPP’s down to 40 mm Hg
Intracranial Pressure (ICP) • In head injury, ICP > 20-25 mm Hg may be more detrimental than low CPP (increasing CPP may not afford protection from intracranial hypertension). • Aggressive attempts to maintain CPP > 70 should be avoided due to ARDS (Level II) • CPP<50 should be avoided (Level III)
Checklist • Definitions • Glasgow Coma Scale • Intracranial Pressure • Mechanisms of brain injury • Evaluation of head injury • Management of head injury • Operative • Nonoperative
Mechanisms of Traumatic Brain Injury • Impact injury • Cerebral or brainstem contusions • Cerebral lacerations • Diffuse axonal injury (DAI) • Secondary injury • Intracranial hematoma • Edema • Ischemia
Checklist • Statistics • Definitions • Glasgow Coma Scale • Intracranial Pressure • Mechanisms of brain injury • Evaluation of head injury • Management of head injury • Operative • Nonoperative
History LOC +/- Intoxicants Seizure Posttraumatic amnesia Physical Exam GCS Level of consciousness Cranial nerves Fundoscopic exam Motor exam Initial Assessment Start with ABC’s
Radiographic Evaluation • CT • Imaging study of choice for initial work-up • MRI • More helpful later in hospital course • Skull x-rays • Arteriography
Indications for CT • Presence of any criteria placing patient at moderate or high risk for intracranial injury • Assessment prior to general anesthesia for other procedures
Checklist • Definitions • Glasgow Coma Scale • Intracranial Pressure • Mechanisms of brain injury • Evaluation of head injury • Management of head injury • Operative • Nonoperative
Head Injury Management • Nonoperative • Seen in absence of significant intracranial mass lesion. • Typically consists of assessment and/or treatment of intracranial pressure (ICP). • Operative • Typically required when a significant intracranial mass lesion is present. • Decompressive craniectomy or brain resection less common.
Head Injury Management • Nonoperative • Seen in absence of significant intracranial mass lesion. • Typically consists of assessment and/or treatment of intracranial pressure (ICP). • Operative • Typically required when a significant intracranial mass lesion is present. • Decompressive craniectomy or brain resection less common.
Nonoperative Management • Frequent neuro checks • Frequent neuro checks • Frequent neuro checks • ICP monitoring
Indications for ICP Monitoring • No data to support Level I recommendation • Severe head injury (GCS 3-8) with abnormal CT (Level II) • Severe head injury (GCS 3-8) with normal CT and 2 of the following (Level III): • Age > 40 years • Unilateral or bilateral motor posturing • SBP < 90 mm Hg • Mild-moderate head injury at discretion of treating physician
Indications for ICP Monitoring • Loss of neurological examination • Sedation • General anesthesia
Clinical Scenario • 20 y.o. male in MVA • Intubated • Score 1T • Eyes open to pain • Score 2 • Briskly localizes • Score 5 • Total GCS 8T
Therapy for Intracranial Hypertension • First tier • Positioning • Ventricular drainage • Osmotic diuresis • Hyperventilation (Level III – temporizing measure) • Second tier • Sedation • Neuromuscular blockade • Hypothermia • Barbiturate coma • Glucocorticoids not recommended (Level I)
Head Injury Management • Nonoperative • Seen in absence of significant intracranial mass lesion. • Typically consists of assessment and/or treatment of intracranial pressure (ICP). • Operative • Typically required when a significant intracranial mass lesion is present. • Decompressive craniectomy or brain resection less common.
Operative Management • Types of mass lesions • Epidural hematoma • Subdural hematoma • Cerebral contusion • Decompressive craniectomy/brain resection
Epidural Hematoma (EDH) • 1% of head trauma admissions • Male: Female = 4:1 • Source of bleeding is arterial in 85% of cases (middle meningeal artery) • Mortality ranges from 5-10% with optimal management • Neurological injury caused by secondary mechanisms
Subdural Hematoma (SDH) • About twice as common as EDH • Mortality 50-90% • Impact injury much higher than with EDH • Often associated brain injury • Two common sources of bleeding • Tearing of bridging veins • Cortical laceration
Cerebral Contusion • Often little mass effect • Not often operative
Hemicraniectomy Pre-op Post-op
Key Points • 2 mechanisms of brain injury • Impact injury • Secondary injury • GCS < 8 has generally become accepted as representing coma / severe head injury • CT is generally the imaging study of choice in the acute assessment of head injury • Operative and nonoperative strategies are generally aimed at reducing mass effect and, therefore, reducing ICP • Nothing beats a neuro exam.