[Use of high-flow oxygen treatment in the emergency medical service: what are the dangers for users from the perspective of occupational and fire protection?] / Anwendung von "High-flow"-Sauerstoff-Therapie im Rettungsdienst: Welche Gefahren ergeben sich für Anwender aus der Perspektive des Arbeits- und Brandschutzes?

INTRODUCTION: The administration of high concentrations of oxygen may harm patients or paramedics by increasing the probability of fire. The presented work investigated the effect of oxygen applied via high flow in different concentrations and flow rates on environmental oxygen concentrations in the patient compartment of an ambulance. RESULTS: Environmental oxygen concentrations increased rapidly over time and oxygen is stored in blankets and clothes over a long period. Simulation in a fire laboratory showed that also in high oxygen concentration settings fire needs a flame or temperatures above 300 °C. Sparks alone were not able to start a fire. CONCLUSION: Ventilation of patient compartment and clothes with ambient air are mandatory to reduce dangerous oxygen concentrations in transport of patients on high-flow oxygen treatment.

Resuscitative endovascular balloon occlusion of the aorta (REBOA) during cardiopulmonary resuscitation: A pilot study.

AIM: Resuscitative endovascular balloon occlusion of the aorta (REBOA) during cardiopulmonary resuscitation (CPR) increases coronary and cerebral perfusion pressure, which might improve neurologically intact survival after refractory cardiac arrest. We investigated the feasibility of REBOA during CPR in the emergency department. METHODS: Patients in refractory cardiac arrest not qualifying for extracorporeal CPR were included in this pilot study. An introducer sheath was placed by ultrasound-guided puncture of the femoral artery, and a REBOA catheter was advanced to the thoracic aorta in 15 patients undergoing CPR. Primary outcome was correct placement within 10 min of skin disinfection. Secondary outcomes included perfusion markers (mean central arterial blood pressure, end-tidal CO2, non-invasively measured cerebral oxygenation) and procedural information (number and duration of attempts, complications, verification of correct position and occlusion). RESULTS: Successful catheter placement was achieved in 9 of the 15 patients (median 9 min 30 s). Median interval from dispatch to start of the procedure was 59 min. A small, albeit significant increase in non-invasively measured cerebral oxygenation was found, but none in blood pressure or end-tidal CO2. However, two patients with pulseless electrical activity of more than 20 min achieved return of spontaneous circulation immediately after REBOA. CONCLUSION: In this pilot trial, REBOA during CPR was successful in 60% of attempts. Long resuscitation times before start of the procedure might explain difficult insertion and missing effects. Nevertheless, insertion of REBOA in patients suffering from non-traumatic cardiac arrest is feasible and might increase coronary and cerebral perfusion pressures and perfusion.

Sonographic patterns of lung consolidation in mechanically ventilated patients with and without ventilator-associated pneumonia: a prospective cohort study.

PURPOSE: Thoracic ultrasound (TUS) has been successfully used in the diagnosis of community-acquired pneumonia. Little is known about its diagnostic potential in ventilator-associated pneumonia (VAP). The purpose of this study was to systematically describe the morphology and temporal changes of sonographic patterns in mechanically ventilated patients and to evaluate the diagnostic performance characteristics of TUS-based VAP diagnoses. MATERIALS AND METHODS: Patients who were placed on invasive ventilation for reasons other than pneumonia and who were considered at risk for the development of VAP received daily TUS examinations while being closely monitored for the development of pneumonia. RESULTS: Fifty-seven patients were studied. The incidence of VAP was 21.1%. Sonographic patterns of reduced or absent lung aeration were found in 64.2% of examinations. The sonographic pattern of lung consolidation with either dynamic or static air bronchograms was 100% sensitive and 60% specific for VAP in those patients who developed clinical signs and symptoms compatible with pneumonia. The pretest and posttest probabilities were 0.38 and 0.6, respectively. CONCLUSIONS: Sonographic patterns of abnormal aeration are frequently observed in mechanically ventilated patients. If sonographic lung consolidation with either static or dynamic air bronchograms is absent, VAP is highly unlikely. The presence of these sonographic patterns in patients with signs and symptoms suggestive of pneumonia significantly increases the probability of VAP.

Current practice of lung ultrasonography (LUS) in the diagnosis of pneumothorax: a survey of physician sonographers in Germany.

BACKGROUND: The purpose of this study was to survey the current practice of the use of lung ultrasonography (LUS) in the diagnosis of pneumothorax. METHODS: Physician sonographers, accredited for diagnostic ultrasonography in surgery, anaesthesia and medicine were studied. Questions addressed the frequency of exposure to patients with suspected pneumothorax, frequency of LUS use, preferences regarding technical aspects of LUS examination, assessment of diagnostic accuracy of LUS and involvement in teaching. RESULTS: Of the respondents, 55.1% used LUS 'always' or 'frequently' for suspected pneumothorax. Also, 35.5% of physicians rated LUS as 'always reliable' in ruling out pneumothorax, and 21.3% of respondents rated LUS as 'always reliable' in ruling in pneumothorax. The mode of performing LUS for pneumothorax was highly variable. Statistically significant differences were found regarding the likelihood of LUS usage, the combined use of M-Mode and B-mode scanning and the confidence to exclude pneumothorax based on LUS findings for physicians with frequent exposure to pneumothorax cases. CONCLUSIONS: Physicians' use of LUS in the diagnosis of pneumothorax is modest. Confidence in diagnostic accuracy is not comprehensive. Further research is required to establish the most efficient way of performing LUS in this scenario to achieve the highest possible diagnostic accuracy and reliable documentation of examination results.