The variables predictive of ambulance non-conveyance of patients in the Western Cape, South Africa.

Introduction: Emergency medical service (EMS) resources are limited and should be reserved for incidents of appropriate acuity. Over-triage in dispatching of EMS resources is a global problem. Analysing patients that are not transported to hospital is valuable in contributing to decision-making models/algorithms to better inform dispatching of resources. The aim is to determine variables associated with patients receiving an emergency response but result in non-conveyance to hospital.
Methods: A retrospective cross-sectional study was performed on data for the period October 2018 to September 2019. EMS records were reviewed for instances where a patient received an emergency response but the patient was not transported to hospital. Data were subjected to univariate and multivariate regression analysis to determine variables predictive of non-transport to hospital.
Results: A total of 245 954 responses were analysed, 240 730 (97.88 %) were patients that were transported to hospital and 5 224 (2.12 %) were not transported. Of all patients that received an emergency response, 203 450 (82.72 %) patients did not receive any medical interventions. Notable variables predictive of non-transport were green (OR 4.33 (95 % CI: 3.55-5.28; p<0.01)) and yellow on-scene (OR 1.95 (95 % CI: 1.60-2.37; p<0.01).Incident types most predictive of non-transport were electrocutions (OR 4.55 (95 % CI: 1.36-15.23; p=0.014)), diabetes (OR 2.978 (95 % CI: 2.10-3.68; p<0.01)), motor vehicle accidents (OR 1.92 (95 % CI: 1.51-2.43; p<0.01)), and unresponsive patients (OR 1.98 (95 % CI: 1.54-2.55; p<0.01)). The highest treatment predictors for non-transport of patients were nebulisation (OR 1.45 (95 % CI: 1.21-1.74; p<0.01)) and the administration of glucose (OR 4.47 (95 % CI: 3.11-6.41; p<0.01)).
Conclusion: This study provided factors that predict ambulance non-conveyance to hospital. The prediction of patients not transported to hospital may aid in the development of dispatch algorithms that reduce over-triage of patients, on-scene discharge protocols, and treat and refer guidelines in EMS.
Competing Interests: At the time of peer review, Dr Willem Stassen and Prof Lee Wallis were editors of the African Journal of Emergency Medicine. Both Dr Stassen and Prof Wallis were not involved in the editorial workflow for this manuscript. The African Journal of Emergency Medicine applies a double blinded process for all manuscript peer reviews. The authors declared no further conflict of interest.
(© 2023 The Authors. Published by Elsevier B.V. on behalf of African Federation for Emergency Medicine.)