Serious conditions among conveyed and non-conveyed patients presenting with nonspecific chief complaints to the ambulance service.

Background: It is a challenge for the ambulance service to identify which patients to convey to the emergency department (ED). Ideally this would be the patients with serious conditions requiring further care in the ED. However, patients presenting with non-specific chief complaints are difficult to prioritize and typically have normal or near normal vital signs despite up to one third having underlying serious conditions. The proportion of patients with serious conditions among non-conveyed patients with non-specific chief complaints (NSC) as assessed by ambulance clinicians is not known. Therefore, the primary aim was to study the proportion of serious conditions among conveyed and non-conveyed patients presenting to the ambulance service with NSCs. The secondary aim was to study the mortality rate among patients with NSCs in relation to conveyance and serious and nonserious conditions.

Method: A retrospective cohort study of patients ≥ 18 years of age presenting with NSCs to the ambulance service in Stockholm Region between January 1st, 2013 and December 31st, 2013. Patients were identified via the ambulance service electronic health record and followed via records from the the National Patient Register and Causes of Death Registry at Sweden's National Board for Health and Welfare. Descriptive statistics as well as regression analyses were used.

Results: A total of 4744 patients were included with a median age of 76 years. A serious condition was present in 1398 (29.5%) of the patients. After index assessment by the ambulance service, 3780 (79.7%) were conveyed of which 1334 (35.3%) had serious conditions, compared to 964 (20.3%) who were non-conveyed of which 64 (6.6%) had serious conditions. 30-day mortality was 372 (9.8%) in the conveyance group compared to 32 (3.3%) in the non-conveyance group. If serious conditions were present, the mortality rates were 269 (20.2%) in the conveyance group compared to 11 (17.2%) in the non-conveyance group.

Conclusion: The results show that serious conditions were more than five times more common among conveyed as compared to non-conveyed patients. Mortality rates were three times higher in the conveyance group as compared to the non-conveyance group. Our results suggest that the ambulance personnel play an important role in identifying patients with serious conditions, hence, likely to be in need of treatment in the ED.

Trial registration: N/A.