Hospital Admissions and 30-Day Mortality Following Non-Conveyance Ambulance Missions in a Norwegian Region: A Retrospective Study

Background: Not all ambulance missions result in patient transport, often referred to as non-conveyance. However, in some cases, patients discharged at the scene may require further examination and treatment. Patient sex, age, and psychiatric disease seem to be factors associated with non-conveyance. This study aimed to identify and characterise patients not transported following an urgent ambulance mission, and to examine subsequent hospital admission and mortality rates. In addition, we wanted to examine their reasons for calling the Emergency Medical Communication Centre (EMCC). Methods: This retrospective study was conducted for the emergency medical system of Norway’s second-largest city. Data, including information from non-conveyed patients involved in acute or urgent ambulance missions over 1 year, were obtained from the EMCC. The frequency of non-conveyance, patient demographics, and incidence of hospital admissions within 72 h were analysed. Furthermore, the 30-day mortality, predictive factors, and reasons for contacting the EMCC were determined. Results: Out of a total of 22,183 ambulance missions, 7.3% of patients were not conveyed, of whom 5.8% were admitted to hospital within 72 h. The 30-day mortality rate among all non-conveyed patients was 2.4%, whereas 2.1% of hospitalised patients died within 30 days. Psychiatric conditions were frequently observed in both groups. The mortality rate increased significantly with age but was not associated with the number of ambulance requests. Furthermore, 30-day mortality was not significantly associated with sex, time of day, day of the week, or rurality. Conclusions: Our data suggests that there is no difference between the short-term outcomes of non-conveyed and conveyed patients; both groups are equally likely to come to harm. Therefore, the factors influencing non-transportation decisions warrant further investigation. Subsequent events following patient discharge should be routinely collected by ambulance services and monitored for learning and to improve the quality of patient care.