The “Vertical Response Time”: Barriers to Ambulance Response in an Urban Area

Abstract

Background: Ambulance response time is typically reported as the time interval from call dispatch to arrival on-scene. However, the often unmeasured ''vertical response time'' from arrival on-scene to arrival at the patient's side may be substantial, particularly in urban areas with high-rise buildings or other barriers to access.

Pediatric Prehospital Evaluation of NYC Cardiac Arrest Survival (PHENYCS)

“…This ''vertical time'' may be a considerable proportion of total response time. 14 The frequency of ventricular cardiac rhythms (VF, ventricular tachycardia [VT]) was only 2.0% (95% CI, 1%Y6%). Other studies of pediatric CA report frequencies of VF/VT 4% to 8% 4,6Y9 to about 10%.…”

Factors affecting the ambulance response times of trauma incidents in Singapore

“…The entire process will include time components such as the scene-time interval (Shin et al, 2014) and scene-to-hospital conveyance times. Another important time component for an urbanized environment with high density housing and commercial settings, such as that of Singapore, is the vertical response times required to reach the patient (Campbell et al, 1993;Morrison et al, 2005;Silverman et al, 2007) Minimizing the delays at each of the time components in the service-delivery of EMS systems is evidently a more complete approach towards the improvement of patient outcomes as compared to the specific focus on ART.…”

A Quantile Regression Analysis of Ambulance Response Time

“…3,13,14 Patient-level factors, such as the patient's age, ethnicity, gender, socioeconomic status, severity of illness, and distance from emergency departments, were found to be associated with ambulance transport interval delays. 3,[15][16][17][18] For example, neighborhoods with high socioeconomic status were found to have shorter out-of-hospital transport intervals for patients with chest pain than neighborhoods with low socioeconomic status. 17 Studies on system-level factors, on the other hand, involved existing EMS infrastructures (e.g., distribution of call centers, capacity for addressing call volumes and volume of concurrent calls, and concentration and availability of ambulance units).…”