Emergency head CT scan ordering and yield: a Malaysian experience

ABSTRACT

The aims of this study were to determine the emergency brain CT scan ordering rate in our emergency department and its positive yield rate; identify significant clinical factors as predictors for scan yield; and evaluate the need for a CT scanner in the emergency department and implementation of guidelines for emergency brain CT scan. This was retrospective study. The study was carried out in UKM hospital, Malaysia from the 1st of January to the 31st of December 2003. The study included all emergency brain CT scans done to 1,687 patients who visited the emergency department of the hospital. Of these patients, 1,088 samples with complete and clear clinical data were studied. The medical records were reviewed retrospectively for selecting these samples. Samples were grouped into trauma and non-trauma. The ordering rate and positive yield rate were calculated and clinical predictors for positive yield were analyzed using Chi-square test. From the total 59,575 patients who visited the emergency department, head CT scan was likely to be helpful in 1,687 patients. A head CT study was requested for these patients. This resulted in an ordering rate of 2.83%. Of the 1,088 samples reviewed, 716 scans showed positive findings, giving the overall scan yield of 65.8%. Non-trauma vases had significant higher scan yield [70.5%]. Age >55 years was noted to have higher risk of positive scans in both groups, especially those presented with seizures. Other significant factors were dysarthria, limb weakness and facial asymmetry in non-trauma cases [all p< 0.05]. The 2.83% ordering rate with 65.8% scan yield signifies the fact that emergency physicians in the study do not order unnecessary CT scan of the head. These findings were noteworthy and might suggest that we revise the request criteria for head CT. however, validated and locally applied CT scan guidelines should be developed and used in order to further enhance its cost-effectiveness in developing countries where resources are limited but its benefits in current and future settings can well be foreseen