Is minor head trauma a contraindication for thrombolysis with tissue Plasminogen Activator (tPA)?

Minor Head Trauma and Thrombolysis

Minor head trauma without loss of consciousness, significant neurological deficit, or radiographic evidence of intracranial hemorrhage is NOT an absolute contraindication to thrombolysis for acute ischemic stroke.

Understanding the Contraindication Framework

The key distinction lies in what constitutes "minor" versus "significant" head trauma in the context of thrombolysis eligibility:

Absolute Contraindications

• Recent significant closed-head or facial trauma WITH radiographic evidence of bony fracture or brain injury is an absolute contraindication to fibrinolysis 1
• Any intracranial hemorrhage (excluding microbleeds) detected on imaging is an absolute contraindication 1
• Recent surgery encroaching on the spinal canal or brain 1

Relative Considerations for Minor Trauma

• Minor injuries, including minor head trauma due to syncope, are NOT necessarily barriers to fibrinolysis 1
• The clinician must judge the relative merits of fibrinolysis on a case-by-case basis 1

Clinical Decision Algorithm

When evaluating a stroke patient with recent minor head trauma:

Step 1: Obtain immediate non-contrast head CT 1

• Exclude intracranial hemorrhage (absolute contraindication) 1
• Assess for skull fractures or brain injury 1

Step 2: Define the severity of head trauma

• Minor trauma: Ground-level fall, bump to head without loss of consciousness, no skull fracture, no intracranial injury on CT 1
• Significant trauma: High-energy mechanism, loss of consciousness, skull fracture, or any intracranial injury on imaging 1

Step 3: Assess stroke severity and time window

• Patients with moderate-to-severe stroke deficits (e.g., aphasia, hemiparesis) derive the greatest benefit from thrombolysis 2
• Treatment window: 0-4.5 hours from symptom onset 2
• Do not delay treatment for additional imaging if within the treatment window 2

Step 4: Make the treatment decision

• If CT shows no hemorrhage, no skull fracture, and no brain injury, proceed with thrombolysis if otherwise eligible 1
• If CT shows any intracranial hemorrhage or significant structural injury, thrombolysis is contraindicated 1
• The presence of minor external trauma alone (scalp laceration, contusion) without intracranial pathology should not prevent thrombolysis 1

Critical Nuances and Common Pitfalls

The "Minor" Designation Matters

The 2011 American Heart Association scientific statement explicitly states that "minor injuries, including minor head trauma due to syncope, are not necessarily barriers to fibrinolysis" 1. This reflects the understanding that many stroke patients fall and sustain minor head trauma as a consequence of their stroke, not as a separate traumatic event.

Antiplatelet Therapy Context

If the patient is on antiplatelet therapy (aspirin, clopidogrel), this creates additional complexity:

• Antiplatelet therapy itself is a relative contraindication to thrombolysis 1
• However, antiplatelet use does not significantly increase bleeding risk after minor head trauma in the absence of intracranial hemorrhage 3, 4
• The decision must weigh stroke severity against bleeding risk 1

Age Considerations

• Age >75 years is a relative contraindication to fibrinolysis 1
• However, age alone should not exclude otherwise eligible patients 2
• Older patients with minor head trauma have higher rates of intracranial injury, making imaging even more critical 5

Time-Critical Nature

Do not delay thrombolysis to obtain additional imaging beyond the initial non-contrast CT if the patient is within the treatment window 2. The benefit of early recanalization outweighs the theoretical risk from minor external trauma when imaging excludes intracranial pathology 2.

Practical Application

For a stroke patient who fell 2 hours ago, bumped their head without loss of consciousness, and now presents with aphasia:

1. Obtain stat non-contrast head CT 1
2. If CT shows no hemorrhage and no skull fracture: Proceed immediately with IV tPA at 0.9 mg/kg 2
3. If CT shows any intracranial hemorrhage: Thrombolysis is contraindicated; consider mechanical thrombectomy if large vessel occlusion 1
4. Do not delay treatment for CTA or MRI if within 4.5 hours and CT is negative 2

The fundamental principle is that imaging findings, not the history of minor trauma alone, determine thrombolysis eligibility 1.