Exploring the knowledge and practice of calcium channel blocker overdose management among South African Emergency Medicine doctors.

Introduction: Calcium channel blocker (CCB) agents have a high mortality rate in overdose (OD) in comparison to other cardiovascular agents. Literature on the emergency management of severe CCB OD is scarce and largely restricted to high-income countries. Within the African context, enhanced knowledge regarding CCB ODs has the potential to reduce mortality and promote adherence to clinical guidelines, provided that practice-related barriers are concurrently addressed. This study aimed to assess the knowledge and practice of emergency department (ED) doctors in managing a CCB OD, use of high dose euglycaemic insulin therapy (HIET), and barriers encountered in CCB OD management. Methods: We conducted a prospective cross-sectional mixed methods survey among 119 South African emergency medicine doctors, from June 2021 until October 2021, to assess their knowledge and practice of managing CCB OD's, using a convenience sampling method. It was a self-administered electronic survey containing 39 questions, including demographics and a combination of open, closed and case-based multiple-choice questions. The closed and multiple-choice questions were analysed using descriptive statistics and chi-square tests to examine associations between demographic variables and responses. Open-ended questions were analysed using thematic content analysis. Results: Of the 119 doctors who participated in the survey, 59 were public ED doctors, 30 were registrars (specialist trainees in emergency medicine), and 30 worked in private EDs. The mean (SD) age of participants was 32.9 years (6.4). The mean (SD) score of all participants was 54% (13.3), which was the lowest for public ED doctors (48%) and significantly higher for private ED doctors (58.4%) and registrars (60.1%). Forty-eight percent of participants didn't know of any guidelines to treat a CCB OD. When asked about their current practice in managing CCB OD, regarding their choice of vasopressor or inotrope, 97.5% ( Discussion: This study has highlighted the need to address ED doctors' knowledge gaps on CCB OD management, further emphasising the importance of clinical toxicology education in South Africa. Although up-to-date guidance is freely accessible, its consistent use appears limited, emphasising the need for improved dissemination and integration into everyday emergency medicine and toxicology practice.