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.
Application of mild hypothermia (32–33°C) has been shown to improve neurological outcome in patients with cardiac arrest, and is therefore a class IIa recommendation in the treatment of those patients. However, hypothermia affects haemostasis, and even mild hypothermia has been found to be associated with bleeding and increased transfusion requirements in patients undergoing surgery [1]. On the other hand, crystalloid hemodilution has been shown to enhance the coagulation onset [2]. Currently, it is unknown in which way the induction of mild therapeutic hypothermia by a bolus infusion of cold crystalloids affects the coagulation system of patients with cardiac arrest.
Laypersons' efforts to initiate basic life support (BLS) in witnessed Out-of-Hospital Cardiac Arrest (OHCA) remain comparably low within western society. Therefore, in order to shorten no-flow times in cardiac arrest, several police-based first responder systems equipped with automated external defibrillators (Pol-AED) were established in urban areas, which subsequently allow early BLS and AED administration by police officers. However, data on the quality of BLS and AED use in such a system and its impact on patient outcome remain scarce and inconclusive.A total of 85 Pol-AED cases were randomly assigned to a gender, age and first rhythm matched non-Pol-AED control group (n = 170) in a 1:2 ratio. Data on quality of BLS were extracted via trans-thoracic impedance tracings of used AED devices.Comparing Pol-AED cases and the control group, we observed a similar compression rate per minute (p = 0.677) and compression ratio (p = 0.651), mirroring an overall high quality of BLS administered by police officers. Time to the first shock was significantly shorter in Pol-AED cases (6 minutes [IQR: 2-10] vs. 12 minutes [IQR: 8-17]; p<0.001). While Pol-AED was not associated with increased sustained return of spontaneous circulation (p = 0.564), a strong and independent impact on survival until hospital discharge (adj. OR: 1.85 [95%CI: 1.06-3.23; p = 0.030]) and a borderline significance for the association with favorable neurological outcome (adj. OR: 1.58 [95%CI: 0.96-2.89; p = 0.052) were observed.We were able to demonstrate an early start and a high quality of BLS and AED use in Pol-AED assessed OHCA cases. Moreover, the presence of Pol-AED care was associated with better patient survival and borderline significance for favorable neurological outcome.
Cardiac arrest (CA) is still associated with high mortality and morbidity. Data on the changes in management and outcomes over a long period of time are limited. Using data from a single emergency department (ED), we assessed changes over two decades.In this single-center observational study, we prospectively included 4133 patients receiving cardiopulmonary resuscitation and being admitted to the ED of a tertiary care hospital between January 1992 and December 2012.There was a significant improvement in both 6-month survival rates (+10.8%; p < 0.001) and favorable neurological outcome (+4.7%; p < 0.001). While the number of witnessed CA cases decreased (-4.7%; p < 0.001) the proportion of patients receiving bystander basic life support increased (+8.3%; p < 0.001). The proportion of patients with initially shockable ECG rhythms remained unchanged, but cardiovascular causes of CA decreased (-9.6%; p < 0.001). Interestingly, the time from CA until ED admission increased (+0.1 hours; p = 0.024). The use of percutaneous coronary intervention and therapeutic hypothermia were significantly associated with survival.Outcomes of patients with CA treated at a specialized ED have improved significantly within the last 20 years. Improvements in every link in the chain of survival were noted.
While guidelines mentioned supraglottic airway management in the case of out-of- hospital cardiac arrest, robust data of their impact on the patient outcome remain scare and results are inconclusive.To assess the impact of the airway strategy on the patient outcome we prospectively enrolled 2224 individuals suffering cardiac arrest who were treated by the Viennese municipal emergency medical service. To control for potential confounders, propensity score matching was performed. Patients were matched in four groups with a 1:1:1:1 ratio ( n=210/group) according to bag-mask-valve, laryngeal tube, endotracheal intubation and secondary endotracheal intubation after primary laryngeal tube ventilation.The laryngeal tube subgroup showed the lowest 30-day survival rate among all tested devices ( p<0.001). However, in the case of endotracheal intubation after primary laryngeal tube ventilation, survival rates were comparable to the primary endotracheal tube subgroup. The use of a laryngeal tube was independently and directly associated with mortality with an adjusted odds ratio of 1.97 (confidence interval: 1.14-3.39; p=0.015). Additionally, patients receiving laryngeal tube ventilation showed the lowest rate of good neurological performance (6.7%; p<0.001) among subgroups. However, if patients received endotracheal intubation after initial laryngeal tube ventilation, the outcome proved to be significantly better (9.5%; p<0.001).We found that the use of a laryngeal tube for airway management in cardiac arrest was significantly associated with poor 30-day survival rates and unfavourable neurological outcome. A primary endotracheal airway management needs to be considered at the scene, or an earliest possible secondary endotracheal intubation during both pre-hospital and in-hospital post-return of spontaneous circulation critical care seems crucial and most beneficial for the patient outcome.
