Quality of focused thoracic ultrasound performed by emergency medical technicians and paramedics in a prehospital setting: a feasibility study

Abstract

Background In a prehospital setting, the severity of respiratory symptoms in patients calling for an ambulance differ. The initial evaluation, diagnosing, and thereby management can be challenging because respiratory symptoms can be caused by disease in many organs. Ultrasound examinations can contribute with important information and support the clinical decision-making. However, ultrasound is user-dependent and requires sufficient knowledge and training. The aim of this study was to explore the quality of thoracic ultrasound examinations performed on patients by emergency medical technicians and paramedics in a prehospital, clinical setting. Methods From November 2018 – April 2020, Danish emergency medical technicians and paramedics (n = 100) performed thoracic ultrasound examinations on patients with respiratory symptoms using a portable ultrasound device. The ultrasound examinations were stored and retrospectively assessed by a reviewer blinded to the patients’ symptoms and history, as well as the emergency medical technicians’ and paramedics’ findings. The image quality was scored from 1 to 5. The findings determined by the reviewer was then correlated with a questionnaire filled out by the emergency medical technicians and paramedics regarding ultrasonic findings and potential change in treatment or management of the patient. The agreement in percentage and as Cohen’s kappa was explored. Results A total of 590 ultrasound examinations were assessed, resulting in a median image quality score of 3 (IQ1 = 4, IQ3 = 3). The overall agreement in percentage between the emergency medical technicians and paramedics and reviewer was high (87.7% for a normal scan, 89.9% for interstitial syndrome, 97.3% for possible pneumothorax, and 96.3% for pleural effusion). Cohen’s kappa varied from 0.01 for possible pneumothorax to 0.69 for pleural effusion. Based on the questionnaires (n = 406), the ultrasound examination entailed a change in treatment or visitation in 48 cases (11.7%) which in this study population encompasses a number-needed-to-scan of 8.5. Conclusion Emergency medical technicians and paramedics perform focused thoracic ultrasound examinations with adequate image quality sufficient to determine if pathology is present or not. The emergency medical technicians’ and paramedics’ assessment correlates to some extent with an experienced reviewer and their findings are most reliable for the inclusion of a normal scan or inclusion of pleural effusion. Implementation could possibly impact the number of patients receiving correct prehospital treatment and optimal choice of receiving facility.

Patients’ perspectives on point-of-care diagnostics and treatment by emergency medical technicians in acute COPD exacerbations: A qualitative study

“…Results from a study with evaluation of the diagnostic quality of point of care focused thoracic ultrasound, Pietersen et al [ 12 ], showed that the EMTs should complete an educational program including a theoretical part and a practical part to be able to obtain the images, interpret the images, and can put the findings into context with other investigations. Our study supports this knowledge as our informants expressed the importance of EMT to appear experienced with the technical equipment in order to instill confidence in the patient.…”

“…Although an elaborate selection process resulted in very few patients being eligible for the study, almost half of the patients that were included in the study were released following treatment. This study was carried out in a prehospital setting in the Region of Southern Denmark from October 1st, 2018 to May 31st, 2019 [ 11 , 12 ]. An overview of the main study is presented with permission in Fig.…”

“…A recent feasibility study from our research group assessed an organisational set-up allowing the EMTs to perform point-of-care diagnostics (lung ultrasound, blood analysis) and initiate treatment when an emergency ambulance was called to the home of a patient with possible COPD exacerbation. The set-up was found to be practically feasible and hospital admission could be avoided in nearly half of the included patients [ 11 , 12 ].…”

“…Furthermore, we aimed to investigate the patients’ attitude towards potentially avoidable admissions to hospitals as well as patients’ experience of stress during point-of-care diagnostics in their own homes. Patients enrolled in this study were drawn from the group of participants who had entered into a previous study [ 11 , 12 ].…”

Remote Real-Time Supervision of Prehospital Point-of-Care Ultrasound: A Feasibility Study

“…[4] [19] Especially in a prehospital setting, lung ultrasound in combination with echocardiography can help to differentiate between cardiac and pulmonary causes of the very common symptom of acute dyspnea in emergency medicine. [4,7,15,20] Limitations:…”