The Canadian head CT rule; a hospital audit

Abstract

Background: Minor head trauma is one of the leading cause of emergency department visits worldwide. The Canadian Head CT-scan rule (CCHR) in minor head injury is an evidence-based aid in decision making as regards to use of CT-scans to detect head injury requiring neuro-intervention. It therefore avoids wastage of resources. The objective was to compare the number of CT-scans done for minor head injury as compared to the number that would have been done if the CCHR was applied.

Methods: A retrospective study was done. All patients resenting with minor head injury (GCS 13-15) were identified from the hospital registry and their files obtained. Patients not meeting the CCHR criteria excluded. Ten parameters were extracted and tabulated.

Results: Forty-one patients were included with three exclusions. 89% (n=34) of the patients presented with a 2-hour GCS of 13 or more. 11% (n=4) were suspicious of base skull fractures. 23% (n=9) had signs of open fracture. Vomiting was seen in 2 patients (5%).  The mean age of patients was 29 years. 2 patients (5%) reported amnesia. All the patients had a CT scan done. Fourteen patients would have required CT scans had the rule been used. Positive findings were noted in seven of the patients who qualified and in three who did not. This demonstrated a 50% positive predictive value, a negative predictive value of 89%, a sensitivity 70% and 75% specificity.

Conclusion: Use of CCHR would reduce unnecessary use of CT scans in minor head injury in this setup.

Keywords: Canadian, head, CT scan, rule, minor head injury