Head CT in Trauma - Clinical Decision Rules

Canadian CT Head Rules (CCHR)

(Stiell IG eg. al Ann Emerg Med, 2001)

Inclusion criteria:

• GCS 13-15
• Age ≥ 16 years
• No coagulopathy
• No obvious open skull fracture

CT indicated if any of following:

• High risk features predictive for neurosurgical intervention:
  • GCS <15 at 2 hours after injury
  • Suspected open or depressed skull fracture
  • Signs of basal skull fracture
  • At least 2 episodes of vomiting
  • Age ≥65 years old
• Medium risk features for brain injury detection on CT:
  • Amnesia before impact of ≥ 30 minutes
  • Dangerous mechanism (pedestrian vs. auto, an occupant ejected from motor vehicle, or a fall from an elevation of ≥ 3 feet or 5 stairs)

New Orleans Criteria (NOC)

(Haydel et. al. NEJM, July 2000)

Inclusion criteria: GCS 15 and loss of consciousness in the setting of trauma

CT indicated if any of the following:

• Headache
• Vomiting
• Age >60 years
• Drugs or alcohol
• Short term memory deficit
• Visible trauma above clavicles
• Seizure

NEXUS-II Criteria

CT indicated if any of following:

(Mower et al. J Trauma, 2005)

• Age ≥65 years old
• Evidence of significant skull fracture
• Scalp hematoma
• Neurologic deficit
• Altered level of alertness
• Abnormal behavior
• Coagulopathy
• Recurrent or forceful vomiting

Comparing Decision Rules

• CCHR vs NOC (Stiell et al. JAMA, 2005)

  • Validation subgroup analysis of 1,822 patients with GCS 15
  • CCHR: Sensitivity 100%, Specificity 50.6% for clinically important intracranial injury
  • NOC: Sensitivity 100%, Specificity 12.7% for clinically important intracranial injury

• CCHR vs NOC (Smits et al. JAMA, 2005)

  • Validation group of 3,181 patients with GCS 13-15
  • CCHR: Sensitivity 87.2%, Specificity 39.7% for clinically important findings
  • NOC: Sensitivity 99.4%, Specificity 5.6% for clinically important findings
  • The NOC had higher sensitivity (99.4%) but a much lower specificity (5.6%).

• CCHR vs NOC vs NEXUS II (Stein et al. Ann Emerg Med, 2009)

  • Validation group of 7,955 patients with GCS 14-15
  • CCHR: Sensitivity 99%, Specificity 47% for clinically important findings
  • NOC: Sensitivity 99%, Specificity 33% for clinically important findings
  • NEXUS II: Sensitivity 97%, Specificity 47% for clinically important findings

References

• Mower WR, Hoffman JR, Herbert M, Wolfson AB, Pollack CV Jr, Zucker MI; NEXUS II Investigators.Developing a decision instrument to guide computed tomographic imaging of blunt head injury patients. J Trauma. 2005 Oct;59(4):954-9. [PubMed]
• Stiell IG, Clement CM, Rowe BH, Schull MJ, Brison R, Cass D, Eisenhauer MA, McKnight RD, Bandiera G, Holroyd B, Lee JS, Dreyer J, Worthington JR, Reardon M, Greenberg G, Lesiuk H, MacPhail I, Wells GA.Comparison of the Canadian CT Head Rule and the New Orleans Criteria in patients with minor head injury. JAMA. 2005 Sep 28;294(12):1511-8. [PubMed]
• Smits M, Dippel DW, de Haan GG, Dekker HM, Vos PE, Kool DR, Nederkoorn PJ, Hofman PA, Twijnstra A, Tanghe HL, Hunink MG.External validation of the Canadian CT Head Rule and the New Orleans Criteria for CT scanning in patients with minor head injury. JAMA. 2005 Sep 28;294(12):1519-25. [PubMed]
• Stein et al. A Critical Comparison of Clinical Decision Instruments for Computed Tomographic Scanning in Mild Closed Traumatic Brain Injury in Adolescents and Adults. Ann Emerg Med, 2009 [Source]
• Haydel MJ, Preston CA, Mills TJ, Luber S, Blaudeau E, DeBlieux PM. Indications for computed tomography in patients with minor head injury. N Engl J Med. 2000 Jul 13;343(2):100-5. [PubMed]
• Stiell IG et al. The Canadian CT Head Rule for patients with minor head injury. Ann Emerg Med, 2001 [Source]