RESUMO
Background: Head computed tomography (head CT) examinations conducted at emergency departments (EDs) for non-trauma patients are expensive and expose patients to ionizing radiation. Identification of symptoms likely to yield abnormal head CT scans can reduce costs and prevent unnecessary patient irradiation. There is limited comprehensive data in the literature concerning the utilization of head CT in low- and middle-income countries (LMICs) EDs. Methods: A retrospective study of successive non-contrasted head CT scans from February 2017 through January 2018 performed on non-trauma ED patients aged 18 years and above without known pre-existing intracranial pathology was conducted. Univariate and multivariate logistic models were used to determine which presenting clinical features were likely to yield abnormal head CT findings. Clinical information was obtained from the history and physical examination findings entered on the requisition form by the ED clinicians and from previous head CT reports if present on the picture archiving and communication system (PACS). Results: A total of 396 consecutive patients who received head CT examinations had a median age of 49 years (IQR: 36-53), and 53.3% were male (n = 211/396). Of the head CT scans included, 73.5% of head CTs included were abnormal (n = 291/396). Age >61 years (aOR:1.54; 95%CI: 1.12-2.10), focal neurologic deficit (aOR: 2.46; 95%CI: 1.42-4.26), and loss of consciousness (aOR 2.82; 95%CI: 1.21-6.57) were the predictors of abnormal head CT findings. Conclusion: A head CT scan in a non-trauma patient presenting to an emergency department in a low-middle income country like South Africa is likely to yield abnormal findings if a patient presented with age above 61 years, loss of consciousness, or focal neurological deficit.
RESUMO
BACKGROUND: Diagnostic investigations using radiation have become a critical feature of medical practice in recent times. However, the possibility of doctors' underestimation of risks of over-exposure of patients to diagnostic radiation still warrants further evaluation. OBJECTIVES: To investigate doctors' awareness of diagnostic radiation exposure at Dr George Mukhari Academic Hospital, South Africa. METHODS: This was a cross-sectional, analytical investigation of the awareness of doctors about radiation exposure in diagnostic radiology investigations. A cluster sampling technique was employed to recruit 217 participants. Consent and approval of the participants were sought and obtained before questionnaire administration during departmental meetings between October 2017 and March 2018. RESULTS: Of the participants, 80% had no formal training on radiation exposure and 33.8% of them correctly estimated natural background radiation. Correct estimates of the effective dose from a single-view abdominal X-ray (AXR) were expressed by 7.5%, quantity of radiation of a single-phase computed tomography (CT) abdomen by 30.3% and dosage from a two-view unilateral mammogram by 29.1% of the participants. More than 75% of participants agreed that children are more sensitive to radiation, but only 10.5% suggested medical termination of pregnancy for a woman who had CT abdomen and pelvis with contrast. Dosage and risk of inducing fatal cancer from common but more complex imaging procedures were poorly understood. Only the doctors of the radiology department showed a statistically significant (p < 0.0001) association with regards to their radiation awareness. CONCLUSION: Because of the high rate of poor awareness of radiation risks observed in this study, it is important to initiate, early in the medical curriculum for medical students, the need for a rotation in the Department of Radiology, similar to such rotations in other medical specialties.