Abstract
Introduction
Centralization of emergency care is expected to increase average pre-hospital time for patients, leading to concerns about possible adverse outcomes for patients. Prior studies have found increased mortality for patients with prolonged transport following acute myocardial infarction.
Purpose
Examine the association between total pre-hospital time (from dispatch to hospital arrival) and mortality for patients, depending on the condition presumed by the emergency dispatcher (presumed heart condition, dyspnea or non-specific medial conditions).
Methods
Pre-hospital registry data from a Danish region from 2006–2012 was used. This contained information on ambulance dispatch priority, ambulance times, and patient condition, as well if procedures consistent with cardiac arrest (CPR or shock) were performed. We included patients with both highest priority dispatch and transport to the hospital. Linkage to nationwide registries of hospital admissions, comorbidities and mortality was performed. Logistic regression was used for analysis.
Results
95% of total pre-hospital times were below 84 minutes. 30-day mortality was highest among patients with dyspnea (36.6%). Compared to pre-hospital times of 0–30 min, odds ratios of 30-day mortality for times >60 min were: for presumed heart conditions 0.54 [95% CI 0.38–0.77] (p<0.001), for dyspnea 0.98 [95% CI 0.65–1.47] and for other medical conditions 1.14 [95% CI 0.98–1.32]
Patient characteristics and outcomes according to the presumed aetiology of the priority 1 emergency dispatch Presumed heart condition Dyspnea Other medical conditions N 1836 1101 11538 Age, median {IQR} 66.4 {55.3, 76.8} 70.5 {56.8, 80.8} 61.5 {40.3, 75.8} Male, n (%) 1194 (65.0) 585 (53.1) 6172 (53.5) 10-year Charlson comorbidity index score ≥3, n (%) 744 (40.5) 613 (55.7) 4311 (37.6) Response time, median {IQR} 9 {5, 13} 9 {5, 13} 8 {5, 13} Total pre-hospital time, median {IQR} 49{37,61} 45{34, 58} 46{34,58} Cardiac arrest procedures during transport, n (%) 266 (14.5) 133 (12.1) 844 (7.3) Cardiovascular diagnosis (DI00-DI99), n (%) 962 (52.4) 282 (25.6) 3285 (28.5) Respiratory diagnosis (DJ00-DJ99), n (%) 82 (4.5) 430 (39.1) 1036 (9.0) 1-day mortality, n (%) 289 (15.7) 225 (20.4) 1311 (11.4) 30-day mortality, n (%) 402 (21.9) 403 (36.6) 2264 (19.6)
Logistic regression, 30-day mortality
Conclusion
No overall association between total pre-hospital time and mortality, however for presumed heart conditions longer times may improve survival.
Acknowledgement/Funding
Program for clinical research infrastructure (PROCRIN) established by the Lundbeck and Novo Nordisk foundations & The Danish Heart Foundation