TY - JOUR

T1 - Ambulance response times and 30-day mortality

T2 - a Copenhagen (Denmark) registry study

AU - Mills, Alexander Andrew Matthew

AU - Mills, Elisabeth Helen Anna

AU - Blomberg, Stig Nikolaj Fasmer

AU - Christensen, Helle Collatz

AU - Møller, Amalie Lykkemark

AU - Gislason, Gunnar

AU - Køber, Lars

AU - Kragholm, Kristian Hay

AU - Lippert, Freddy

AU - Folke, Frederik

AU - Andersen, Mikkel Porsborg

AU - Torp-Pedersen, Christian

N1 - Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.

PY - 2024

Y1 - 2024

N2 - BACKGROUND AND IMPORTANCE: Ensuring prompt ambulance responses is complicated and costly. It is a general conception that short response times save lives, but the actual knowledge is limited.OBJECTIVE: To examine the association between the response times of ambulances with lights and sirens and 30-day mortality.DESIGN: A registry-based cohort study using data collected from 2014-2018.SETTINGS AND PARTICIPANTS: This study included 182 895 individuals who, during 2014-2018, were dispatched 266 265 ambulances in the Capital Region of Denmark.OUTCOME MEASURES AND ANALYSIS: The primary outcome was 30-day mortality. Subgroup analyses were performed on out-of-hospital cardiac arrests, ambulance response priority subtypes, and caller-reported symptoms of chest pain, dyspnoea, unconsciousness, and traffic accidents. The relation between variables and 30-day mortality was examined with logistic regression.RESULTS: Unadjusted, short response times were associated with higher 30-day mortality rates across unadjusted response time quartiles (0-6.39 min: 9%; 6.40-8.60 min: 7.5%, 8.61-11.80 min: 6.6%, >11.80 min: 5.5%). This inverse relationship was consistent across subgroups, including chest pain, dyspnoea, unconsciousness, and response priority subtypes. For traffic accidents, no significant results were found. In the case of out-of-hospital cardiac arrests, longer response times of up to 10 min correlated with increased 30-day mortality rates (0-6.39 min: 84.1%; 6.40-8.60 min: 86.7%, 8.61-11.8 min: 87.7%, >11.80 min: 85.5%). Multivariable-adjusted logistic regression analysis showed that age, sex, Charlson comorbidity score, and call-related symptoms were associated with 30-day mortality, but response time was not (OR: 1.00 (95% CI [0.99-1.00])).CONCLUSION: Longer ambulance response times were not associated with increased mortality, except for out-of-hospital cardiac arrests.

AB - BACKGROUND AND IMPORTANCE: Ensuring prompt ambulance responses is complicated and costly. It is a general conception that short response times save lives, but the actual knowledge is limited.OBJECTIVE: To examine the association between the response times of ambulances with lights and sirens and 30-day mortality.DESIGN: A registry-based cohort study using data collected from 2014-2018.SETTINGS AND PARTICIPANTS: This study included 182 895 individuals who, during 2014-2018, were dispatched 266 265 ambulances in the Capital Region of Denmark.OUTCOME MEASURES AND ANALYSIS: The primary outcome was 30-day mortality. Subgroup analyses were performed on out-of-hospital cardiac arrests, ambulance response priority subtypes, and caller-reported symptoms of chest pain, dyspnoea, unconsciousness, and traffic accidents. The relation between variables and 30-day mortality was examined with logistic regression.RESULTS: Unadjusted, short response times were associated with higher 30-day mortality rates across unadjusted response time quartiles (0-6.39 min: 9%; 6.40-8.60 min: 7.5%, 8.61-11.80 min: 6.6%, >11.80 min: 5.5%). This inverse relationship was consistent across subgroups, including chest pain, dyspnoea, unconsciousness, and response priority subtypes. For traffic accidents, no significant results were found. In the case of out-of-hospital cardiac arrests, longer response times of up to 10 min correlated with increased 30-day mortality rates (0-6.39 min: 84.1%; 6.40-8.60 min: 86.7%, 8.61-11.8 min: 87.7%, >11.80 min: 85.5%). Multivariable-adjusted logistic regression analysis showed that age, sex, Charlson comorbidity score, and call-related symptoms were associated with 30-day mortality, but response time was not (OR: 1.00 (95% CI [0.99-1.00])).CONCLUSION: Longer ambulance response times were not associated with increased mortality, except for out-of-hospital cardiac arrests.

KW - Humans

KW - Ambulances

KW - Reaction Time

KW - Cohort Studies

KW - Out-of-Hospital Cardiac Arrest/therapy

KW - Dyspnea/diagnosis

KW - Registries

KW - Chest Pain

KW - Unconsciousness

KW - Denmark/epidemiology

KW - Emergency Medical Services

U2 - 10.1097/MEJ.0000000000001094

DO - 10.1097/MEJ.0000000000001094

M3 - Journal article

C2 - 37788140

VL - 31

SP - 59

EP - 67

JO - European Journal of Emergency Medicine

JF - European Journal of Emergency Medicine

SN - 0969-9546

IS - 1

ER -