Outpatient Management of Contrecoup Injuries
Most contrecoup injuries require initial hospital-based evaluation with CT imaging and cannot be safely managed as outpatients until clinically stable with documented non-progression of intracranial pathology.
Initial Assessment and Imaging
Contrecoup injuries—brain lesions occurring opposite to the site of impact—require immediate CT scanning to identify the extent of injury, as these injuries can be deceptive and may not correlate with external signs of trauma 1, 2. All patients with suspected contrecoup injury must undergo brain CT without delay to identify primary brain lesions including epidural hematomas, subdural hematomas, and parenchymal contusions 3.
- CT imaging should use inframillimetric sections with double fenestration (central nervous system and bone windows) as the reference standard 1
- Consider CT-angiography if risk factors for vascular injury exist, including cervical spine fracture, focal neurological deficits not explained by brain imaging, or basal skull fractures 1
Criteria for Outpatient Management
Outpatient management is only appropriate after initial hospital evaluation confirms:
- Normal or minimal findings on CT scan with no mass effect, no midline shift, and no significant hematoma 3
- Glasgow Coma Scale of 15 with no neurological deficits 2, 4
- No signs of increased intracranial pressure (pupillary abnormalities, hypertension, bradycardia) 1, 5
- Hemodynamic stability with systolic blood pressure >110 mmHg 3
Critical Pitfall to Avoid
Deterioration after a lucid interval occurs in 71% of cases within 24 hours, and mass lesions are found in 81% of patients who deteriorate 1. This makes early discharge extremely risky. Even small contrecoup epidural hematomas can enlarge rapidly, particularly with vomiting or increased intracranial pressure 2, 6.
Observation Period Requirements
- Minimum 24-hour hospital observation is essential for any patient with documented contrecoup injury on CT, even if initially asymptomatic 1, 2
- Repeat CT imaging at 6-8 hours if any clinical change occurs (vomiting, altered consciousness, new neurological deficits) 2, 6
- Contrecoup extradural hematomas without fracture are extremely rare but can enlarge unpredictably 4
Discharge Criteria for Outpatient Follow-up
Patients may transition to outpatient management only after:
- Completion of 24-hour observation period without clinical deterioration 1
- Repeat CT demonstrates stable or resolving findings with no new lesions 2
- Patient remains neurologically intact with GCS 15 4
- Reliable caregiver available for home monitoring 1
Outpatient Monitoring Protocol
Once discharged, patients require:
- Strict return precautions: immediate return for worsening headache, vomiting, confusion, seizures, focal weakness, or vision changes 1, 5
- Neurological checks every 2-4 hours for first 48 hours at home by a responsible adult 1
- Follow-up CT in 1-2 weeks to confirm resolution, particularly for patients with any residual findings on discharge imaging 2, 4
- Neurosurgical follow-up within 1 week for patients with documented hematomas managed conservatively 2
Activity Restrictions
- Avoid activities that increase intracranial pressure: no heavy lifting, straining, or Valsalva maneuvers for 2-4 weeks 1
- No contact sports or high-risk activities for minimum 4-6 weeks until cleared by neurosurgery 5
- Avoid anticoagulants and antiplatelet agents unless absolutely necessary 3
Indications for Immediate Hospital Readmission
Transfer immediately to neurosurgical center if:
- Any decline in consciousness or new neurological deficits develop 3, 1
- Persistent vomiting occurs (can increase ICP and expand hematomas) 2, 6
- Severe or worsening headache despite analgesics 1
- Seizure activity 5
Special Consideration
Contrecoup injuries can involve white matter tracts (such as the prefronto-thalamic tract) causing cognitive dysfunction and mood changes that may not be immediately apparent 7. Patients should be counseled about potential delayed cognitive and psychiatric symptoms requiring neuropsychological evaluation 7.