II. Epidemiology
-
Incidence: 1.7 Million Traumatic brain injuries in U.S. per year
- Minor Head Injury in 75% of cases
- Hospitalizations: 275,000
- Deaths: 52,000
III. Pathophysiology
-
Intracranial Pressure (ICP) association with injury
- Note measurements are in mmHg, not cmH2O
- Normal: 10 mmHg ICP
- Abnormal: 20 mmHg ICP
- Severe: 40 mmHg ICP
- Herniation: 50 mmHg ICP
-
Cushing's Response
- Hypertensive response in face of increased ICP
- Helps maintain cerebral perfusion
- Do not use Antihypertensives to lower Blood Pressure
- Results in decreased brain perfusion
- Exception: Intracranial Bleeding (e.g. aneurysmal bleeding)
IV. Precautions: Cardiopulmonary status in Head Injury
- Target PaO2: 200-300 mmHg
- Avoid Hyperventilation following intubation
- Hyperventilation is associated with worse outcomes in Traumatic Brain Injury
- Monitor End-Tidal CO2 or capnometer following intubation
- Maintain pCO2 at 35-40 mmHg (avoid pCO2 <25 mmHg)
- Maintain Respiratory Rate at 10-12 breaths per minute
- Avoid Hypotension
- Maintain systolic Blood Pressure >=100-110 mmHg (ATLS-10)
- References
- Majoewsky (2012) EM:RAP 12(5): 1-2
- Davis (2009) J Neurotrauma 26(12): 2217-23 [PubMed]
V. History
- See Concussion
- Medical History
- See AMPLE History
- Medications (e.g. Anticoagulants, antiplatelet agents, antiepileptics)
- Intoxicants (Alcohol, drugs)
- Pregnancy
- Time and mechanism of injury
- High severity accident (e.g. death at scene, high speed accident, unrestrained, ejection)
- Loss of Consciousness
- How long?
- Contiguous with initial injury?
- Events preceding impaired consciousness and Trauma (e.g. Syncope, Thunderclap Headache)
-
Level of Consciousness (AVPU)
- Immediately post injury
- Subsequent evaluations
- Amnesia (Retrograde or antegrade)
- Headache
- Seizures
- Symptoms of Increased Intracranial Pressure
- Blurred Vision
- Severe Headache with Nausea, Vomiting
VI. Evaluation: General
- Systematic evaluation (unless isolated Minor Head Injury)
- See Trauma Evaluation (includes Primary Survey)
- See Secondary Trauma Evaluation
-
Glasgow Coma Scale (GCS)
- First GCS at the initial emergency Trauma Evaluation is the best indicator of outcome at one year
- Goal in Trauma is to optimize care and allow the best chance for recovery to the initial GCS
- Pupil exam
-
Neurologic Exam (baseline and with neurologic change during evaluation)
- See Coma Exam
- Eye Neurologic Exam
- Motor Exam
- Sensory Exam
- Reflex Exam
- Coordination Exam
-
Vital Signs
- Hypertension is typical response (see Cushing's Response above)
- Hypotension seen in pediatric Closed Head Injury
- Cushing Triad (Increased Intracranial Pressure)
- Wide Pulse Pressure
- Bradycardia
- Irregular breathing pattern
- Signs Skull Fracture
- See Skull Fracture
- Vault Skull Fracture
- Basilar Skull Fracture
- CSF Rhinorrhea or Otorrhea
- Hemotympanum
- Post-auricular Bruising (Battle's Sign)
- Orbital Bruising (Raccoon's Eyes)
- CN VII palsy (Bell's Palsy)
- Signs impending Cerebral Herniation
- Declining Level of Consciousness or progressive neurologic deficits
- Pupil Dilation and loss of Pupillary Light Reflex (unilateral or bilateral)
- Decorticate Posturing (arms flexed, legs extended)
- Decerebrate Posturing (arms and legs extended)
- Cushing Triad (wide Pulse Pressure, Bradycardia, irregular breathing)
- Signs Intracranial Injury
-
Scalp Lacerations with Hemorrhage
- Risk of significant blood loss to the point of Hemorrhagic Shock (especially children)
- Apply direct pressure to prevent further bleeding
- Close bleeding scalp lesions quickly (even temporarily) with Sutures, staples or Raney Clips
- Carefully investigate Laceration for associated complications prior to final closure
- Skull Fracture (deformity, bony fragments, CSF Leakage)
- Subgaleal Hemorrhage may appear similar to Skull Fracture with deformity at the floor of the Laceration
VII. Evaluation: Age under 2 years
- See Head Injury CT Indications in Children
- Red Flags suggestive of serious injury
- Skull Fracture
- Scalp swelling (80-100% of Skull Fracture)
- Younger the age, the greater the risk
- Non-accidental Trauma (Child Abuse)
- No clear history of Trauma
- Symptoms that do not predict serious Head Injury
- Loss of consciousness
- Vomiting
- References
- Dachs (2012) AAFP Board Review Express, San Jose
VIII. Imaging: Head and Neck
-
CT Head
- Obtain in all cases of moderate or Severe Head Injury
- C-Spine imaging indications
- Brain injury is associated with Spinal Injury in 5% of cases
- See Cervical Spine Imaging in Acute Traumatic Injury
- See NEXUS Criteria
- Mild Head Injury Imaging Indications
IX. Management: Coagulopathy or oral Anticoagulant (e.g. Warfarin, Plavix)
- See Anticoagulant Reversal
- Approach based on evidence below
- Consider imaging all patients on Anticoagulants regardless of Head Injury severity
- Consider repeat CT Head imaging at 24 hours for patients on Warfarin regardless of signs or symptoms
- Consider 24 hour observation and repeat CT Head for elderly patients or those with INR >3
- Newman in Herbert (2014) EM:Rap 14(1): 6
- Even Minor Head Injury on oral Anticoagulants is associated with significant bleeding risk (often without red flags)
- Clopidogrel was associated with an initial 12% CNS HemorrhageIncidence, but no delayed bleeding
- Warfarin was associated with an initial 6% CNS HemorrhageIncidence with 0.6% having delayed bleeding
- Nishijima (2012) Ann Emerg Med 59(6): 460-8 [PubMed]
- Antiicoagulants (esp. Warfarin) are associated with delayed Intracranial Bleeding
- One study demonstrated 6% of patients at 24 hours
- Bleeding may be delayed as long as 1 week after Head Injury
- Most patients with CNS Hemorrhage on Warfarin had GCS 14-15 and no focal neurologic changes
- Menditto (2012) Ann Emerg Med 59(6): 451-5 [PubMed]
- Other studies demonstrated a 0.4 to 1.4% risk of delayed Intracranial Hemorrhage
- In these studies, delayed head bleeding required neurosurgical intervention is rare
- Borst (2021) Surgery 170(2):623-7 +PMID: 33781587 [PubMed]
- Campiglio (2017) Neurol Clin Pract 7(4): 296-305 +PMID: 29185534 [PubMed]
- Cohan (2020) J Trauma Acute Care Surg 89(2):301-10 +PMID: 32332255 [PubMed]
- Hill (2018) Brain Inj 32(6):735-8 +PMID: 29485294 [PubMed]
- Kaen (2010) J Trauma 68(4):895-8 +PMID: 20016390 [PubMed]
- Lim (2016) Am J Emerg Med 34(1): 75-8 +PMID: 26458530 [PubMed]
- Turcato (2022) Am J Emerg Med 53:185-9 +PMID: 35063890 [PubMed]
- Conservative repeat Head CT protocol
- Repeat Head CT in 6-12 hours unless criteria below are met
- Most patients are observed in hospital while awaiting repeat Head CT
- Repeat Head CT not needed in minor Head Trauma if all of following criteria met (expert opinion)
- Initial Head CT negative (including no Skull Fracture and no Soft Tissue Injury) AND
- INR <2.5 AND
- Age < 65 years old AND
- Glasgow Coma Scale 15 AND
- Non-focal exam AND
- No persistent Emesis
- Repeat Head CT in 6-12 hours unless criteria below are met
- As of 2023, repeat Head CT after minor Trauma on Anticoagulants has become less common
- Delayed head bleed requiring intervention is rare following minor Head Trauma on Anticoagulants (see above)
- Early discharge after first CT relies on patient with normal baseline Neurologic Exam
- Use Shared Decision Making with patient regarding repeat Head CT
- Give the patient clear return precautions for changes in neurologic status
- One study demonstrated 6% of patients at 24 hours
X. Associated Conditions
XI. Management
- See Management of Mild Head Injury (GCS 13-15 at two hours)
- See Concussion (mildest subset of Mild Traumatic Brain Injury)
- See Management of Moderate Head Injury (GCS 9-12 at two hours)
- See Management of Severe Head Injury (GCS 3-8 at two hours)
- Avoid Systemic Corticosteroids (increases mortality)
- Avoid Progesterone (does not improve outcomes in TBI)
XII. References
- (2012) ATLS, ACOS, Chicago, p. 149-73
- Abuguyan (2024) Crit Dec Emerg Med 38(7): 4-11