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Three Part Question

In [anticoagulated patients with minor head injury and initial negative head CT scan] does a [repeat head CT scan] improve [clinical outcome]?

Clinical Scenario

An 80 year old man with a history of atrial fibrillation on warfarin presents to the emergency department after a ground level fall. He reports hitting his head, but denies loss of consciousness. Vital signs are stable and within normal limits at presentation, GSC is 14. Physical exam is unremarkable. Initial head CT scan is read as negative for acute abnormality without evidence of intracranial hemorrhage. Can the patient safely be discharged home?

Search Strategy

PubMed: [Head CT] and [Trauma or Head Injury] and [Anticoagulation or Anticoagulant] limit to English language, humans

Search Outcome

Altogether 133 papers were found, 6 were relevant to the clinical question and of sufficient quality for inclusion. Details of the five most relevant papers are found in Table 1.

Relevant Paper(s)

Author, date and country	Patient group	Study type (level of evidence)	Outcomes	Key results	Study Weaknesses
Kaen, A. 2010 Spain	-137 adult patients on preinjury anticoagulation with minor head injury and normal initial head CT scan. All patients underwent 24 hours of observation and a repeat head CT scan prior to discharge. -Patients with traumatic intracranial hemorrhage on initial CT scan were excluded	Prospective, observational study	-Presence of intracranial hemorrhage on repeat head CT scan -Neurological deterioration -Neurosurgical intervention required -Death	- 2 of 137 patients demonstrated intracranial hemorrhage on repeat head CT scan (1.4%) - 0 of 137 patients demonstrated neurological deterioration or required neurosurgical intervention - The 2 patients with intracranial hemorrhage on repeat head CT were 2 of 3 patients in the study on both anticoagulant and antiplatelet therapy.	-Observational study -Potential for selection bias -Small sample size
Peck, KA 2011 USA	- 424 adult blunt trauma patients receiving anticoagulant or prescription antiplatelet therapy with a normal initial head CT scan. -Patients with traumatic intracranial hemorrhage on initial CT scan were excluded	Retrospective review	-Presence of intracranial hemorrhage on repeat head CT scan 6hrs following initial negative head CT -Neurological deterioration -Readmission rates	- 4 of 362 patients who received repeat head CT scan demonstrated intracranial hemorrhage (1%) -None of these were found to be clinically significant - 3 of 4 were discharged home, 1 died of unrelated cause	Repeat head CT scan not obtained in 15% of patients with an initial negative head CT scan.
Nishijima DK 2012 USA	- 1,064 adult patients with blunt head trauma and preinjury warfarin or clopidogrel use within 7 days of injury, regardless of LOC. -687 of these patients were on preinjury warfarin -Patients with traumatic intracranial hemorrhage on initial CT scan were excluded	Prospective, observational, multicenter	-Presence of immediate intracranial hemorrhage -Presence of delayed intracranial hemorrhage -Neurosurgical intervention required -Death	-Delayed traumatic intracranial hemorrhage was identified in 4 of 687 patients on preinjury warfarin (0.6%) and 0 of the 243 patients on preinjury clopidogrel (0%)	-Observational study -Potential for selection bias -Due to ethical considerations, definitive repeat head CT scans were not obtained on all patients
Schoonman, GG 2014 The Netherlands	- 211 adult patients on preinjury oral anticoagulation with minor traumatic brain injury (GSC 13-15) and LOC <60min with a normal initial head CT scan. Pt must have been on oral anticoagulant for >1 week with an INR >1.1 -Patients with traumatic intracranial hemorrhage on initial CT scan were excluded	Retrospective review	-Presence of intracranial hemorrhage on repeat head CT scan -Neurological deterioration -Neurosurgical intervention required -Death	- 5 of 211 patients were found to have intracranial hemorrhage on repeat head CT, but in retrospect only 2 of these patients had initially negative head CT scans -Therefore, only 2 of 211 patients developed intracranial hemorrhage after initial negative head CT scan (.09%) -Intracranial hemorrhage in both of these patients occurred >19 days after injury	-Misinterpretation of 3 initial head CT scans incorrectly inflated number of new intracranial hemorrhages found on repeat head CT scan.

Clinical Bottom Line

Repeat head CT scans are not indicated in anticoagulated patients with minor head injuries following initial negative head CT scan. Randomized controlled trials are needed to establish evidence-based decision rules for this patient population.

References

1. Kaen A, Jimenez-Roldan L, Arrese I, Delgado MA, Lopez PG, Alday R, Alen JF, Lagares A, Lobato RD. The value of sequential computed tomography scanning in anticoagulated patients suffering from minor head injury. J Trauma 2012 Jun;59(6):451-5.
2. Peck KA, Sise BC, Shackford SR, Sise MJ, Calvo RY, Sack DI, Walker SB, Schechter MS. Delayed intracranial hemorrhage after blunt trauma: are patients on preinjury anticoagulation and prescription antiplatelet agents at risk? J Trauma 2011 Dec;71(6):1600-1604.
3. Menditto VG, Lucci M, Polonara S, Pomponio G, Gabrielli A. Management of minor head injury in patients receiving oral anticoagulant therapy: a prospective study of a 24-hour observation protocol. Annals of Emergency Medicine 2012 Jun;59(6):451-5.
4. Nishijima DK, Offerman SR, Ballard DW, Vinson DR, Chettipally UK, Rauchwerger AS, Reed ME, Holmes JF Immediate and delayed traumatic intracranial hemorrhage in patients with head trauma and preinjury warfarin or clopidogrel use. Annals of Emergency Medicine 2012 Jun;59(6):460-8.e1-7.
5. Schoonman GG, Bakker DP, Jellema K. Low risk of late intracranial complications in mild traumatic brain injury patients using oral anticoagulation after an initial normal brain computed tomography scan:education instead of hospitalizati Eur J Neurol. 2014 Jul;21(7):1021-5.