MIA 2012: Nishijima DK et al. Immediate and delayed traumatic intracranial hemorrhage in patients with head trauma and preinjury warfarin or clopidogrel use. Ann Emerg Med. 2012 Jun;59(6):460-8.e1-7.

Bottom Line

CREST study: Patients presenting to the emergency room with blunt head trauma and preinjury warfarin or clopidogrel use have a high incidence of immediate intracranial hemorrhage, but a very low incidence delayed intracranial hemorrhage. Thus, if the initial head CT is negative, you should be able to discharge the patient home...

Why It’s Important for Emergency Medicine 

Every physician can intuit that patients being treated with anticoagulation or antiplatelet medications are at an increased risk of bleed in the setting of blunt head trauma. This prospective study gives us a good idea of the incidence of immediate ICH in an anticoagulated population. More importantly, it established that the risk of delayed ICH (traumatic ICH diagnosed within 2 weeks of injury after a normal CT) was extremely low, about 1 delayed bleed out of 200. This should allow for the safe discharge of those who are otherwise well with a negative head CT - a group whom was previously routinely admitted, or even had their anticoagulation reversed. It is emphasized that these patients should be given good instructions, and probably have someone with them to watch them.

Major Points

Warfarin group
  • 37/724 (5.1%) had immediate ICH
  • 4/687 (0.6%) suffered delayed ICH
Plavix group 
  • 33/276 (12.0%) had immediate ICH
  • 0/243 suffered delayed ICH
Design & Results
  • Prospective observational study; 2 trauma centers and 4 community hospitals. 
  • Inclusion: Any degree of blunt head trauma + preinjury warfarin or plavix use within the last 7 days. 
  • Patients using both plavix + warfarin were excluded. Follow-ups were obtained from either hospital records or phone calls. 
  • 1101 enrolled, 1064 included. 4 lost to followup. 87.6% were GCS 15, 34.2% were admitted. 
  • 7.0% had immediate ICH, 0.4% had delayed ICH. 
Criticisms
  • There was significantly more aspirin use in the plavix group. This could possibly account for the increased incidence of immediate ICH. There is no data for those just on ASA. 
  • Repeat CT’s were obtained at the physician’s discretion. 
  • Was there a population of missed ‘asymptomatic’ delayed ICH? If so, does it matter? 
  • Patients on warfarin may be more aware of their bleeding risk, leading to a lower threshold to present after blunt trauma, accounting for the difference in ICH between plavix and warfarin. In fairness, the clinical attributes between the warfarin and plavix groups are very similar. 
Reviewed by A. Williams

Reference
Nishijima DK, Offerman SR, Ballard DW, Vinson DR, Chettipally UK, Rauchwerger AS, Reed ME, Holmes JF; Clinical Research in Emergency Services and Treatment (CREST) Network. Immediate and delayed traumatic intracranial hemorrhage in patients with head trauma and preinjury warfarin or clopidogrel use. Ann Emerg Med. 2012 Jun;59(6):460-8.e1-7. Pubmed

MIA 2012 = Most Interesting Articles series of 2012