Head Injury

See Also
Page Contents

Page Contents...
Epidemiology
Pathophysiology
Precautions: Cardiopulmonary status in Head Injury
History
Evaluation: General
Evaluation: Age under 2 years
Imaging: Head and Neck
Management: Coagulopathy or oral Anticoagulant (e.g. Warfarin, Plavix)
Associated Conditions
Management
References
Extra: Related Bing Images
Extra: Related Studies
Extra: UMLS Ontology
Extra: Navigation Tree

II. Epidemiology

Incidence: 1.7 Million Traumatic brain injuries in U.S. per year
1. Minor Head Injury in 75% of cases
2. Hospitalizations: 275,000
3. Deaths: 52,000

III. Pathophysiology

Intracranial Pressure (ICP) association with injury
1. Note measurements are in mmHg, not cmH2O
2. Normal: 10 mmHg ICP
3. Abnormal: 20 mmHg ICP
4. Severe: 40 mmHg ICP
5. Herniation: 50 mmHg ICP
Cushing's Response
1. Hypertensive response in face of increased ICP
2. Helps maintain cerebral perfusion
3. Do not use Antihypertensives to lower Blood Pressure
  1. Results in decreased brain perfusion
  2. Exception: Intracranial Bleeding (e.g. aneurysmal bleeding)

IV. Precautions: Cardiopulmonary status in Head Injury

Target PaO2: 200-300 mmHg
1. PaO2 <200 mmHg and PaO2 >300 mmHg are both associated with higher mortality
2. Option 1: Wean FIO2 to 50%, but still maintain O2Sat at 99-100% or
3. Option 2:
  1. Wean oxygen to point that O2Sat starts to drop below 99-100% and
  2. Then increase the delivered oxygen by 2-4 L/min above that level
Avoid Hyperventilation following intubation
1. Hyperventilation is associated with worse outcomes in Traumatic Brain Injury
2. Monitor End-Tidal CO2 or capnometer following intubation
3. Maintain pCO2 at 35-40 mmHg (avoid pCO2 <25 mmHg)
4. Maintain Respiratory Rate at 10-12 breaths per minute
Avoid Hypotension
1. Maintain systolic Blood Pressure >=100-110 mmHg (ATLS-10)
References
1. Majoewsky (2012) EM:RAP 12(5): 1-2
2. Davis (2009) J Neurotrauma 26(12): 2217-23 [PubMed]

V. History

See Concussion
Medical History
1. See AMPLE History
2. Medications (e.g. Anticoagulants, antiplatelet agents, antiepileptics)
3. Intoxicants (Alcohol, drugs)
4. Pregnancy
Time and mechanism of injury
1. High severity accident (e.g. death at scene, high speed accident, unrestrained, ejection)
Loss of Consciousness
1. How long?
2. Contiguous with initial injury?
3. Events preceding impaired consciousness and Trauma (e.g. Syncope, Thunderclap Headache)
Level of Consciousness (AVPU)
1. Immediately post injury
2. Subsequent evaluations
Amnesia (Retrograde or antegrade)
Headache
Seizures
Symptoms of Increased Intracranial Pressure
1. Blurred Vision
2. Severe Headache with Nausea, Vomiting

VI. Evaluation: General

Systematic evaluation (unless isolated Minor Head Injury)
1. See Trauma Evaluation (includes Primary Survey)
2. See Secondary Trauma Evaluation
Glasgow Coma Scale (GCS)
1. First GCS at the initial emergency Trauma Evaluation is the best indicator of outcome at one year
2. 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)
1. See Coma Exam
2. Eye Neurologic Exam
3. Motor Exam
4. Sensory Exam
5. Reflex Exam
6. Coordination Exam
Vital Signs
1. Hypertension is typical response (see Cushing's Response above)
2. Hypotension seen in pediatric Closed Head Injury
  1. Patrick (2002) Am J Surg 184:555-60 [PubMed]
3. Cushing Triad (Increased Intracranial Pressure)
  1. Wide Pulse Pressure
  2. Bradycardia
  3. Irregular breathing pattern
Signs Skull Fracture
1. See Skull Fracture
2. Vault Skull Fracture
3. Basilar Skull Fracture
  1. CSF Rhinorrhea or Otorrhea
  2. Hemotympanum
  3. Post-auricular Bruising (Battle's Sign)
  4. Orbital Bruising (Raccoon's Eyes)
  5. CN VII palsy (Bell's Palsy)
Signs impending Cerebral Herniation
1. Declining Level of Consciousness or progressive neurologic deficits
2. Pupil Dilation and loss of Pupillary Light Reflex (unilateral or bilateral)
3. Decorticate Posturing (arms flexed, legs extended)
4. Decerebrate Posturing (arms and legs extended)
5. Cushing Triad (wide Pulse Pressure, Bradycardia, irregular breathing)
Signs Intracranial Injury
1. Focal
2. Diffuse
  1. Mild Concussion
  2. Classic Concussion
  3. Diffuse Axonal Injury
Scalp Lacerations with Hemorrhage
1. Risk of significant blood loss to the point of Hemorrhagic Shock (especially children)
2. Apply direct pressure to prevent further bleeding
3. Close bleeding scalp lesions quickly (even temporarily) with Sutures, staples or Raney Clips
4. Carefully investigate Laceration for associated complications prior to final closure
  1. Skull Fracture (deformity, bony fragments, CSF Leakage)
  2. 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
1. Skull Fracture
2. Scalp swelling (80-100% of Skull Fracture)
3. Younger the age, the greater the risk
4. Non-accidental Trauma (Child Abuse)
5. No clear history of Trauma
Symptoms that do not predict serious Head Injury
1. Loss of consciousness
2. Vomiting
References
1. Dachs (2012) AAFP Board Review Express, San Jose

VIII. Imaging: Head and Neck

CT Head
1. Obtain in all cases of moderate or Severe Head Injury
C-Spine imaging indications
1. Brain injury is associated with Spinal Injury in 5% of cases
2. See Cervical Spine Imaging in Acute Traumatic Injury
3. See NEXUS Criteria
Mild Head Injury Imaging Indications
1. See Head Injury CT Indications in Adults
2. See Head Injury CT Indications in Children
  1. Consider Head MRI in children in place of Head CT (due to radiation risk)

IX. Management: Coagulopathy or oral Anticoagulant (e.g. Warfarin, Plavix)

See Anticoagulant Reversal
Approach based on evidence below
1. Consider imaging all patients on Anticoagulants regardless of Head Injury severity
2. Consider repeat CT Head imaging at 24 hours for patients on Warfarin regardless of signs or symptoms
3. Consider 24 hour observation and repeat CT Head for elderly patients or those with INR >3
4. 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)
1. Clopidogrel was associated with an initial 12% CNS Hemorrhage Incidence, but no delayed bleeding
2. Warfarin was associated with an initial 6% CNS Hemorrhage Incidence with 0.6% having delayed bleeding
3. Nishijima (2012) Ann Emerg Med 59(6): 460-8 [PubMed]
Antiicoagulants (esp. Warfarin) are associated with delayed Intracranial Bleeding
1. One study demonstrated 6% of patients at 24 hours
  1. Bleeding may be delayed as long as 1 week after Head Injury
  2. Most patients with CNS Hemorrhage on Warfarin had GCS 14-15 and no focal neurologic changes
  3. Menditto (2012) Ann Emerg Med 59(6): 451-5 [PubMed]
2. Other studies demonstrated a 0.4 to 1.4% risk of delayed Intracranial Hemorrhage
  1. In these studies, delayed head bleeding required neurosurgical intervention is rare
  2. Borst (2021) Surgery 170(2):623-7 +PMID: 33781587 [PubMed]
  3. Campiglio (2017) Neurol Clin Pract 7(4): 296-305 +PMID: 29185534 [PubMed]
  4. Cohan (2020) J Trauma Acute Care Surg 89(2):301-10 +PMID: 32332255 [PubMed]
  5. Hill (2018) Brain Inj 32(6):735-8 +PMID: 29485294 [PubMed]
  6. Kaen (2010) J Trauma 68(4):895-8 +PMID: 20016390 [PubMed]
  7. Lim (2016) Am J Emerg Med 34(1): 75-8 +PMID: 26458530 [PubMed]
  8. Turcato (2022) Am J Emerg Med 53:185-9 +PMID: 35063890 [PubMed]
3. Conservative repeat Head CT protocol
  1. Repeat Head CT in 6-12 hours unless criteria below are met
    1. Most patients are observed in hospital while awaiting repeat Head CT
  2. Repeat Head CT not needed in minor Head Trauma if all of following criteria met (expert opinion)
    1. Initial Head CT negative (including no Skull Fracture and no Soft Tissue Injury) AND
    2. INR <2.5 AND
    3. Age < 65 years old AND
    4. Glasgow Coma Scale 15 AND
    5. Non-focal exam AND
    6. No persistent Emesis
4. As of 2023, repeat Head CT after minor Trauma on Anticoagulants has become less common
  1. Delayed head bleed requiring intervention is rare following minor Head Trauma on Anticoagulants (see above)
  2. Early discharge after first CT relies on patient with normal baseline Neurologic Exam
  3. Use Shared Decision Making with patient regarding repeat Head CT
  4. Give the patient clear return precautions for changes in neurologic status

X. Associated Conditions

XI. Management

See Management of Mild Head Injury (GCS 13-15 at two hours)
1. 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)
1. Roberts (2004) Lancet 364:1321-8 [PubMed]
Avoid Progesterone (does not improve outcomes in TBI)
1. Wright (2014) N Engl J Med 371(26): 2457-66 +PMID:25493974 [PubMed]
2. Skolnick (2014) N Engl J Med 371(26): 2467-76 +PMID:25493978 [PubMed]

XII. References

(2012) ATLS, ACOS, Chicago, p. 149-73
Abuguyan (2024) Crit Dec Emerg Med 38(7): 4-11

Images: Related links to external sites (from Bing)

These images are a random sampling from a Bing search on the term "Head Injury." Click on the image (or right click) to open the source website in a new browser window. Search Bing for all related images