Appropriateness of head computed tomography scan in mild traumatic head injury among adult patients in Mulago National Referral Hospital, Kampala

Abstract

Background: Computed Tomographic (CT) scanning of the head is an excellent imaging modality to identify acute intracranial injury, and to identify patients requiring neurosurgical intervention. The inappropriate utilization of CT scan strains the meagre imaging resources and risks the patients to unnecessary radiation that has a potential risk of leading to radiation induced cancers. The Canadian CT head rule (CCHR) is a validated and widely researched clinical tool used to predict which Mild head injury (MHI) patients will have a clinically significant intracranial injury (ICI) on head CT scan and consequently reduce the number of requested CT scans performed while at the same time ensuring that those who would benefit from it are easily identified. Objective: The purpose of this study was to determine the appropriateness of head CT scans performed among patients with mild traumatic head injury based on the Canadian CT head rule (CCHR) at the emergency department (ED) of Mulago National Referral Hospital, Kampala. Methods: This was a cross sectional study of 259 adults clinically diagnosed with mild head injury in the emergency department of Mulago National referral Hospital. The participants with mild head injury and able to obtain a head CT scan within one week of injury were recruited. They were assessed using the CCHR for a prediction of whether a head CT scan done was appropriate or inappropriate. This was correlated with their head CT scan findings. The participants were followed up with a phone call after two weeks to assess their health status. Data was collected using a structured questionnaire which was entered into a computer using Epi Info. It was then analyzed using STATA version 14.0. Categorical variables were analyzed and presented as frequencies and percentages in tables, pie charts and graphs. Results: The male: female ratio was 7:1 with majority 147 (56.8%) of the participants in the age group of 18-29 years. The most common symptoms were loss of consciousness, headache, dizziness and history of blood loss. Majority of the participants 212(81.9%) had a GCS of 15. The most prominent neurologically significant head CT scan findings were comminuted and depressed skull fractures 44(17.1%). The proportion of appropriate head CT scans performed based on the CCHR was 70.7%. Most participants with positive CT scan findings were classified as appropriately performed CT scan when the CCHR was applied. 62(81.6%) of the participants classified as inappropriately performed CT scan had normal findings. There was a statistically significant association between categories of CCHR classification (appropriate vs inappropriate) and CT scan findings (normal vs neurologically insignificant) p<0.001. Conclusion: Mild head injury was most prevalent among the young male adults with depressed and comminuted skull fractures being the most common abnormal head CT scan findings. This study was able to determine the appropriateness of the head CT scans performed in patients with mild head injury based on the CCHR in the emergency department of MNRH. About one-third of head CT scans currently performed on adults with mild traumatic head injury in MNRH may be avoidable by applying the CCHR and avoidance of CT scan in such patients is unlikely to miss any important injuries. Findings from the study can guide the adoption and adaptation of CCHR use in the emergency department of hospitals in Uganda.