Prehospital emergency medicine research by additional teams on scene - Concepts and lessons learned.

While the initial minutes of acute emergencies significantly influence clinical outcomes, prehospital research often receives inadequate attention due to several challenges. Retrospective chart reviews carry the risk of incomplete and inaccurate data. Furthermore, prehospital intervention trials frequently encounter difficulties related to extensive training requirements, even during the planning phase. Consequently, we have implemented prospective research concepts involving additional paramedics and physicians directly at the scene during major emergency calls. Three concepts were used: (I) Paramedic field supervisor units, (II) a paramedic + physician field supervisor unit, (III) a special physician-based research car. This paper provides insights into our historical perspective, the current situation, and the lessons learned while overcoming certain barriers and using existing and novel facilitators. Our objective is to support other research groups with our experiences in their planning of upcoming prehospital trials.

Prehospital triage optimization of patients with large vessel occlusion by Austrian Prehospital Stroke Scale.

OBJECTIVES: The Austrian Prehospital Stroke Scale (APSS) score was developed to predict large vessel occlusion (LVO) and improve prehospital transportation triage. Its accuracy has been previously analyzed retrospectively. We now aimed to investigate the accuracy, as well as the impact of the implementation of a triage strategy using this score on treatment times and outcome in a prospective study. MATHERIAL & METHODS: Prospective diagnostic test accuracy and before-after interventional study. EMS prospectively evaluated APSS in patients suspected of stroke. Accuracy was compared with other LVO scores. Patients with APSS ≥4 points were brought directly to the comprehensive stroke center. Treatment time frames, neurological, and radiological outcome before and after the APSS implementation were compared. RESULTS: A total of 307 patients with suspected stroke were included from October 2018 to February 2020. Treatable LVO was present in 79 (26%). Sensitivity of APSS to detect those was 90%, specificity 79%, positive predictive value 66%, negative predictive value 95%, and area under the curve 0.87 (95% CI 0.83-0.91). This was similar to in-hospital NIHSS (AUC 0.89 95% CI 0.89-0.92, p = .06) and superior to CPSS (AUC 0.83 95% CI 0.78-0.87, p = .01). Implementation of APSS triage increased direct transportation rate for LVO patients (21% before vs. 52% after; p < .001) with a significant time benefit (alert to groin puncture time benefit: 51 min (95% CI 28-74; p < .001). Neurological and radiological outcome did not differ significantly. CONCLUSIONS: Austrian Prehospital Stroke Scale triage showed an accuracy comparable with in-hospital NIHSS, and lead to a significant optimization of prehospital workflows in patients with potential LVO.

Management of EMS on-scene time during advanced life support in out-of-hospital cardiac arrest: a retrospective observational trial.

OBJECTIVE: Most western emergency medical services provide advanced life support in out-of-hospital cardiac arrest aiming for a return of spontaneous circulation at the scene. Little attention is given to prehospital time management in the case of out-of-hospital cardiac arrest with regard to early coronary angiography or to the start of extracorporeal cardiopulmonary resuscitation treatment within 60 minutes after out-of-hospital cardiac arrest onset. We investigated the emergency medical services on-scene time, defined as emergency medical services arrival at the scene until departure to the hospital, and its association with 30-day survival with favourable neurological outcome after out-of-hospital cardiac arrest. METHODS: All patients of over 18 years of age with non-traumatic, non-emergency medical services witnessed out-of-hospital cardiac arrest between July 2013 and August 2015 from the Vienna Cardiac Arrest Registry were included in this retrospective observational study. RESULTS: Out of 2149 out-of-hospital cardiac arrest patients, a total of 1687 (79%) patients were eligible for analyses. These patients were stratified into groups according to the on-scene time (<35 minutes, 35-45 minutes, 45-60 minutes, >60 minutes). Within short on-scene time groups, out-of-hospital cardiac arrest occurred more often in public and bystander cardiopulmonary resuscitation was more common (both P<0.001). Patients who did not achieve return of spontaneous circulation at the scene showed higher rates of 30-day survival with favourable neurological outcome with an on-scene time of less than 35 minutes (adjusted odds ratio 5.00, 95% confidence interval 1.39-17.96). CONCLUSION: An emergency medical services on-scene time of less than 35 minutes was associated with higher rates of survival and favourable outcomes. It seems to be reasonable to develop time optimised advance life support protocols to minimise the on-scene time in view of further treatments such as early coronary angiography as part of post-resuscitation care or extracorporeal cardiopulmonary resuscitation in refractory out-of-hospital cardiac arrest.

Out of hospital cardiac arrest in Vienna: incidence and outcome.

AIM OF THE STUDY: To determine the incidence of out-of-hospital cardiac arrest and the survival rate of those patients who received CPR in the city of Vienna. METHODS: A cohort of patients with out-of-hospital cardiac arrests and who were treated by the Vienna Ambulance Service between January 1, 2009, and December 31, 2010, were followed up until either death or hospital discharge. The associations of survival and neurological outcome with their potential predictors were analysed using simple logistic regression models. Odds ratios were estimated for each factor. RESULTS: During the observation period, a total of 7030 (206.8/100,000 inhabitants/year) patients without signs of circulation were assessed by teams of the Vienna Ambulance Service, and 1448 adult patients were resuscitated by emergency medical service personnel. A sustained return of spontaneous circulation was reported in 361 (24.9%) of the treated patients, and in all 479 (33.0%) of the patients were taken to the emergency department. A total of 164 (11.3%) of the patients were discharged from the hospital alive, and 126 (8.7%) of the patients showed cerebral performance categories of 1 or 2 at the time of discharge. Younger age, an arrest in a public area, a witnessed arrest and a shockable rhythm were associated with a higher probability of survival to hospital discharge. CONCLUSION: Survival rates for out-of-hospital cardiac arrests remain low. Efforts should be focused on rapidly initiating basic life support, early defibrillation, and high-quality CPR by emergency medical services and state-of-the art post-resuscitation care.