Background
Methods
Eligibility criteria
Outcome measures
Information sources
Search strategy and study selection
Data collection
Assessment of quality of evidence
Results
First author, year | n | Study type | Aim | US types, providers | Main results | Rating |
---|---|---|---|---|---|---|
Cardiac arrest only | ||||||
Aichinger, 2012 | 42 | Prospective, observational (cohort) | To evaluate the ability of heart US to predict outcome in cardiac arrest | Heart (cardiac standstill y/n) Novice physicians | Feasibility 100%. 1/32 patients with cardiac standstill vs. 4/10 patients with cardiac movement survived to hospital discharge (p = 0,008). Cardiac standstill 97.1% PPV for death at scene. | + |
Reed, 2017 | 45 | Prospective, observational (cohort) | To evaluate the ability of paramedics to perform heart US during pulse check | Heart Extensively trained paramedics | Adequate view in first attempt in 80% of patients, but prolonged pauses in compressions – median 17 s (IQR 13–20). | + |
Rooney, 2016 | 19 | Cohort | To determine if paramedics could perform cardiac ultrasound in the field and correctly identify cardiac activity/standstill | Heart Novice paramedics | A total of 17/19 (89, 95% CI 67–99) exams were adequate for clinical decision-making. Correct identification of 17/17 cases of cardiac activity and 2/2 cases of cardiac standstill. | + |
Chest pain | ||||||
No studies | ||||||
Suspected stroke | ||||||
Herzberg, 2014 | 102 | Diagnostic accuracy | To evaluate the accuracy of transcranial US for neurovascular emergency diagnostics | Transcranial color-coded US in combination with clinical examination Experienced neurologists | Any stroke: sensitivity 94%, specificity 48% Major stroke: sensitivity 78%, specificity 98% | 0 |
Breathing difficulties | ||||||
Neesse, 2012 | 56 | Diagnostic accuracy | To evaluate the feasibility and diagnostic value of a chest ultrasound algorithm in dyspnea | Heart, anterior lungs, dorsolateral pleura Certified physicians | US helpful tool in 38/56 (68%) patients, additional therapeutic consequences drawn in 14/56 (25%). Pleural effusion found to be a 100% sensitive marker for congestive heart failure. | + |
Laursen, 2016 | 40 | Diagnostic accuracy | To assess feasibility, time-use and diagnostic accuracy of lung ultrasound for cardiogenic pulmonary edema | Anterior and lateral part of the lungs (4 regions, B-lines only) Novice physicians | Feasibility 100%. Median time used 3 min. Sensitivity 94% (CI 73–100), specificity 77% (CI 55–92), PPV 77% (CI 55–92), NPV 94% (CI 73–100) | + |
Strnad, 2016 | 20 | Prospective, observational (cohort) | To determine the usefulness of lung ultrasound in treatment monitoring with CPAP vs standard treatment in CHF | Anterior and lateral part of the lungs (15 regions), B-lines only. Physicians | Lower total number of B-lines after than before CPAP (p < 0.001). Percentage of positive US lung scans significantly reduced in several regions in the CPAP group. Changes in B-lines correlated with improved vital signs. | 0 |
Trauma | ||||||
Brun, 2014 | 98 | Cluster-randomized (controlled) | To compare the feasibility and efficiency of eFAST on-site, during transfer, or both | Lungs, heart, abdomen (PTX, tamponade, hemothorax, hemoperitoneum y/n) Physicians, heterogenous experience | On-site: feasibility 95.4%, efficiency 95% During transfer: feasibility 93.9%, efficiency 97% Both: feasibility 95.2%, efficiency 100% No difference between groups (w = 0.68) | – |
Press, 2014 | 293 | Diagnostic accuracy | To determine the accuracy of each component of trauma ultrasound performed by HEMS providers | Lungs, heart, abdomen (PTX, tamponade, hemothorax, hemoperitoneum y/n) Flight nurses/paramedics | Hemoperitoneum: sensitivity 46% (CI 27–94), specificity 94% (CI 89–97). Laparotomy: sensitivity 65% (CI 39–85), specificity 94%(CI 89–97). Pneumothorax: sensitivity 19% (CI 9–34), specificity 99.5% (CI 98.2–99.9). Thoracostomy: sensitivity 50% (CI 22–59), specificity 99.8% (CI 98.6–100) | + |
Yates, 2017 | 190 | Observational, controlled | To correlate prehospital trauma ultrasound findings to inhospital trauma team findings | Lungs, heart, abdomen (PTX, tamponade, hemothorax, hemoperitoneum y/n). Flight nurses/paramedics | PPV 100% NPV 98.3% Equivalent to in-hospital trauma team ultrasound | 0 |
First author, year | n | Study type | Aim | US types, providers | Main results | Rating |
---|---|---|---|---|---|---|
Mixed populations | ||||||
Quick, 2016 | 149 patients | Controlled (prehospital paramedics vs in-hospital physicians) | To evaluate the ability of ability of in-flight thoracic US to identify pneumothorax (trauma and medical patients) | Lung (PTX), paramedics compared to ED physicians | Gold standard chest CT (n = 116). Prehospital sensitivity of 68% (95% CI 46–85), specificity 96% (95% CI 90–98), accuracy 91% (95% CI 85–95). Physician-based ED US; sensitivity 84% (95% CI 62–94), specificity 98% (95% CI 93–99), accuracy 96% (95% CI 90–98). | + |
O’Dochertaigh, 2017 | 455 missions | Cohort | To describe the use of US to support interventions when used by physicians and non-physicians (trauma and medical patients) | Trauma ultrasound and IVC, highly trained physicians and non-physicians (paramedics) | Interventions was supported in US in 26% (95% CI 18–34) of cases when used by non-physicians, and in 45% (95% CI 34–56) when used by physicians (p < 0.006) | 0 |
Roline, 2013 | 71 (41 scans) | Cohort | To evaluate the feasibility of bedside thoracic US (trauma and medical patients) | Lung (PTX), prehospital care providers (paramedics?) | In 71 eligible patients, 41 (58%) scans were completed. Level of agreement between flight crew and expert substantial with a kappa of 0.67, (95% CI 0.44–0.90). 54% of images were rated “good”. Causes for not completing US were lack of time or space limitation in aircraft. | + |
Ketelaars, 2013 | 281 patients, 326 exams | Cohort | To evaluate the impact of US chest examinations on the care of patients in a HEMS service (trauma and cardiac arrest patients) | Heart, lung (PTX), abdomen, experienced physicians | PTX sensitivity 38%, specificity 97%, PPV 90%, NPV 69%. Treatment plan changed in 60 (21%) patients; in 10 (4%) a chest tube was abandoned; in 10 (4%) the destination for definitive care was changed, in 9 (3%) cardiopulmonary resuscitation was stopped and in 31 (11%) there were other changes. | + |
Procedural guidance | ||||||
Chenaita, 2012 | 130 patients | Diagnostic accuracy | To estimate the diagnostic accuracy of US confirmation of gastric tube placement | Abdominal (gastric), experienced physicians | Sensitivity 98.3% (95% CI 94–99.5), specificity 100% (95% CI 75.7–100). PPV 100%, NPV 85.7%. Correlation between gastric tube size and visualization (larger tubes easier to see) | + |
Brun, 2014 | 32 | Controlled study (2-point US vs syringe test) | To estimate the diagnostic accuracy of 2-point US to confirm gastric tube placement | Esophageal, abdominal, physicians | 100% visualization of gastric tube in the esophagus, 62.5% in the stomach. X-ray confirmed 28/32 in correct position. US higher diagnostic accuracy than syringe test. | 0 |
Zadel, 2015 | 124 patients | Diagnostic accuracy | To assess the sensitivity and specificity of US for confirming endotracheal intubation | Lung (lung sliding and diaphragm excursion), certified physicians | Gold standard, capnography. US sensitivity 100%, specificity 100%, PPV 100%, NPV 100%. Median US time 30 s. | 0 |
First author, year | n | Study type | Aim | Education program | Main results | Rating |
---|---|---|---|---|---|---|
Short course | ||||||
Chin, 2012 | 20 paramedics | Cohort | To determine if paramedics can acquire and interpret US for pneumothorax, pericardial effusion and cardiac activity | 2-h session – 1 h lecture and 1 h hands-on session | After-test only: All subjects could identify the pleural line and 19/20 could obtain a cardiac view suitable for interpretation. Test score results were 9.1 out of a possible 10 (95% CI 8.6–9.6). | 0 |
West, 2014 | 10 paramedics | Diagnostic accuracy | Not specified, but tested diagnostic accuracy for free fluid in abdominal trauma ultrasound | 4 h course with lectures and hands-on training | Detecting of free fluid after course (peritoneal dialysis patients). Sensitivity 67%, specificity 56%. Higher false-positive rate than false-negative rate (59% vs 41%, p < 0.01) | 0 |
Bhat, 2015 | 57 EMTs, paramedics and students | Controlled (before-and-after) | To assess the ability of EMS providers and students to accurately interpret heart and lung US images | 1 h lecture on PTX, pericardial effusion and cardiac standstill | Theoretical test before and after: Test score 62.7% vs 91.1%. 95% CI for change 22–30%, p < 0.001). New post test in 19 subjects after one week: 93.1%. | + |
Rooney, 2016 | 4 paramedics, 19 patients | Cohort | To determine if paramedics could perform cardiac ultrasound in the field and correctly identify cardiac activity/standstill | 3 h course with 2 h theory and 1 h hands-on training | A total of 17/19 (89, 95% CI 67–99) exams were adequate for clinical decision-making. Correct identification of 17/17 cases of cardiac activity and 2/2 cases of cardiac standstill. | + |
1- or 2-day course | ||||||
Charron, 2015 | 100 exams | Diagnostic accuracy | To assess the ability of emergency physicians to obtain and interpret heart and inferior vena cava views using portable US | 2-day course | Parasternal short axis, long axis and subcostal views were adequate in 44, 46 and 46%, respectively. Apical 4-chamber was adequate in 67%. Agreement with experts was weak for LVF, RV size and pericardial effusion and very weak for IVC. | + |
Paddock, 2015 | 36 paramedics, nurses and physicians | Randomized controlled study | To compare the effectiveness of training using an ultrasound simulator to traditional trauma ultrasound training | Group A: Traditional training. Group B: US simulator training. Group C: Both | No difference between groups on neither image acquisition skills nor theoretical knowledge scores. | + |
Booth, 2015 | 11 paramedics (4 long-term) | Controlled (before-and-after) | To determine if paramedics can be trained to perform and interpret US of the heart in cardiac arrest | 1-day course with 2 h theory and 4 h hands-on training. | Theoretical test before and after: Improved theoretical knowledge (test score 54% before vs 89% after, p < 0.001). Practical test only after: 88% success in image acquisition during 10-min pulse-check window. Reduced to 75% (3/4) after 10 weeks. | – |
Krogh, 2016 | 40 physicians | Controlled (before-and-after) | To evaluate the effect of e-learning and a hands-on US course of the lungs, heart, and abdomen | 1-day course with 120 min e-learning + 4 h hands-on course | Improvement in theoretical knowledge after e-learning compared to before (51.3 (SD 5.9) vs 37.5 (SD 10.0), p < 0.001). Improvement in practical US performance and image interpretation after hands-on compared to before (p < 0.001). | + |
Longer program | ||||||
Press, 2013 | 33 paramedics and nurses | Controlled (before-and after) | To evaluate the effectiveness of a trauma US training curriculum and to determine if demographic factors predicted successful completion | 1-day course with 2 h lectures, 4 h hands-on training + proctored session (4 exams) during 6 weeks + 60–120 min e-learning + unsupervised real-life exams | Theoretical test: none passed pre-test, 28/33 passed post-test with 78% score (p > 0.001 for difference). 27/33 passed structured clinical examination – only demographic factor predicting passing structured clinical exam was passing theoretical post-test. | + |
Bobbia, 2015 | 14 physicians, 85 patients | Controlled (on experience-level) | To evaluate the interpretability of prehospital heart US based on physician experience | Experienced and non-experienced physicians defined by more or less than 50 exams after initial training (theory, 25 supervised exams) | Eight (57%) experienced physicians performed 51 (60%) exams and 6 (43%) novice physicians performed 34 (40%) exams. In multivariate analysis, only physicians experience was associated with the number of interpretable items (96% vs 56% for LVF, 98% vs 29% for PE, 92% vs 26% for RVD, and 67% vs 21% for IVC) | + |
Botker, 2017 | 24 physicians | Controlled (before-and-after) | To evaluate the effect of a systematical education program in US of the heart and pleura on image acquisition skills, use and barriers | 4 h e-learning + 1-day hands-on course + 10 supervised examinations + 3 months unsupervised exams | Proportion of images useful for interpretation increased from 0.70 (95% CI 0.65–0.75) to 0.98 (95% CI 0.95–0.99), p < 0.001. Used by 21/21 (100%) of prehospital providers after 4 years. Barriers for prehospital use comprised image quality in difficult patients and equipment | + |