Emergency ultrasound is performed at the point of care to quickly answer focused clinical questions. Over the last 25 years, the use of this technique has expanded rapidly. The use of emergency ultrasound in the pediatric setting is increasing because it does not expose the patient to ionizing radiation, as compared to computed tomography (CT). Utilizing diagnostic point-of-care ultrasound (POCUS) for pediatric trauma patients in the emergency department (ED) can facilitate diagnosis at the bedside rather than sending the patient out of the department for another study. This supplement focuses on some of the common indications for diagnostic POCUS that may be useful in the setting of trauma, as found in the pediatric literature, or extrapolated from adult literature where pediatric evidence is scarce.
The use of ultrasound at the point of care by emergency clinicians, as well as by other specialists, has become increasingly common over the last 25 years. Emergency POCUS can be used as a diagnostic test and also to visualize anatomy for procedural guidance. It allows the emergency clinician to rapidly rule in or rule out disease processes and guide ongoing investigation and management of patients in the ED. POCUS is a skill required by the Accreditation Council for Graduate Medical Education for emergency medicine residency training,1 and it is supported by many organizations, including the American Medical Association, the American Academy of Pediatrics, the American College of Emergency Physicians, the American Board of Emergency Medicine, and the American Institute for Ultrasound in Medicine.
Pediatric emergency ultrasound has been slower to progress than adult emergency ultrasound. Of the more than 120 emergency ultrasound fellowships currently listed on the Society for Clinical Ultrasound Fellowships website, only 14 are pediatric-specific. However, the use of emergency ultrasound for pediatric patients has recently begun to formalize. The American Academy of Pediatrics, along with several emergency medicine and ultrasound societies, released a policy statement in 2015 that supported the use of POCUS by pediatric emergency physicians.2 In 2016, a review was published that reported guidelines and training objectives for pediatric-specific POCUS applications.3 Most pediatric emergency medicine fellowship directors now consider POCUS to be an essential skill and many include formal POCUS training in their curricula.4
The pediatric patient is arguably more suited for emergency ultrasound than the adult patient. Children generally have a smaller body habitus than adults and, therefore, less tissue for the ultrasound beams to penetrate. This often leads to clearer images of the different organ systems, which should yield better diagnostic accuracy. There has been sparse data to support this assumption, due to a lack of comparative studies of the populations. The largest meta-analyses pooled together adult and pediatric patients without separately assessing the diagnostic accuracy of this testing in adults and children, even for the most basic emergency ultrasound technique, the focused assessment with sonography for trauma (FAST) examination.5-10
Children are an ideal target population in which to increase the use of emergency ultrasound. Exposure to ionizing radiation from CT scans may lead to an increased incidence of cancer.11-13 Pediatric cells divide at a faster rate than adult cells, so pediatric patients have a greater risk of harm from ionizing radiation compared to adults. The number of CT scans performed overall has increased 5-fold over the last 20 years, and it is widely believed that an increased incidence of cancer directly linked to medical imaging will be seen.14 One large retrospective epidemiological study found a small, but significant, increase in cancer related to CT scanning in the first decade of life. The study predicted that, among patients aged < 10 years who received a CT scan, there would be 2 cases of excess cancer (cancer that would not have occurred without the CT scans) per 10,000 CT scans in the decade following the scan.15 With an estimated 4 million CT scans being performed annually in pediatric patients,16 it is incumbent on healthcare providers to find alternate diagnostic methods for these patients. Ultrasound has been shown to have a high diagnostic accuracy for many pathologies, without the associated risks of ionizing radiation.
Diagnostic ultrasound for pediatric patients has traditionally been in the domain of pediatric radiologists and technicians who are skilled in the interpretation of ultrasound for pediatric-specific pathologies. Many centers do not have access to pediatric radiologists or do not have access to pediatric ultrasound during evening and night hours. These centers generally transfer pediatric patients who need medical and surgical care to tertiary care centers with pediatricians and pediatric surgeons. However, ultrasound technology has improved to include portable ultrasound machines and ultrasound transducers that can be attached to smartphones. If the emergency clinician can make or rule out a diagnosis at the bedside, transfer to the appropriate facility can be expedited and unnecessary transfers avoided.
A literature search was performed in PubMed to identify relevant articles pertaining to each of the modalities discussed, utilizing combinations of the following search terms: diagnostic emergency ultrasound, pediatric, cardiac, pericardial effusion, tamponade, cardiac arrest, ejection fraction, focused assessment with sonography in trauma, FAST, pelvic trauma, extended focused assessment sonography in trauma, E-FAST, skull, forearm, lung, and testicular torsion. Original research, systematic reviews, and meta-analyses were the primary literature reviewed. If there was a lack of original research, case reports and case series were evaluated and presented. Additionally, previous reviews were used to identify relevant literature. Critical appraisal for specific indications will be discussed in the relevant sections.
Before pediatric data became available, most of the evidence for the utility of pediatric emergency ultrasound was derived from adult literature. However, there are important differences in the efficacy of pediatric emergency ultrasound compared to adult emergency ultrasound. While the FAST examination is the most widely used and accepted emergency ultrasound modality in adults, its diagnostic accuracy in children has been shown to be poor.5,17 Fortunately, the emergency ultrasound field is expanding very rapidly, and more emergency ultrasound research is being conducted than ever before. It is, therefore, expected that more pediatric emergency ultrasound data will be available in the near future. This supplement will focus on the pediatric-specific emergency ultrasound literature. Where there is a paucity of pediatric data in the emergency setting, adult emergency ultrasound data or pediatric radiology data will be presented.
Ultrasound has been investigated for use in the prehospital setting. It is used widely in Europe,18 but is less often used in this setting in North America.19 In a recent survey of emergency medical services (EMS) directors in the United States and Canada, the most common reasons for not implementing prehospital ultrasound were equipment and training costs, as well as a lack of evidence that it reduces patient morbidity and mortality.19 Two systematic reviews, 1 for trauma and 1 for nontrauma, concluded that there was insufficient evidence that prehospital ultrasound improves patient outcomes.20,21 There are no randomized controlled trials in this area, and there are no studies in the pediatric setting in particular. Most of the studies are from the trauma setting and assessed patients of all ages, while some excluded pediatric patients.
Despite the lack of evidence on patient outcomes, there is evidence that ultrasound is feasible and accurate in the prehospital setting when performed either by physicians or nonphysician clinicians, especially in the context of trauma.21 Studies evaluating the feasibility of ultrasound included adult patients, and, therefore, may not reflect feasibility in pediatric patients. A prospective multicenter British study looked at FAST performed by EMS personnel and physicians on adults and children with suspected blunt or penetrating abdominal trauma. For the 202 patients completing the protocol, they found a sensitivity of 93% and a specificity of 99% as confirmed by hospital ultrasound or CT. Furthermore, prehospital management was altered in 30% of cases and the choice of admitting to the hospital changed in 22% of cases.22 Of note, because FAST has been shown to be less accurate in pediatric patients as compared to adult patients and because the results of this study were not separated between pediatric patients and adult patients, the accuracy of FAST in this study cannot be extrapolated to the pediatric population. In a Korean study, FAST performed by EMS personnel was found to have a similar diagnostic accuracy compared to FAST performed by physicians.23 Lyon et al randomized a cadaver to tracheal or esophageal intubations to assess prehospital critical care clinician accuracy in the diagnosis of lung sliding on ultrasound. After a 9-month period without additional teaching, the prehospital clinicians maintained a sensitivity and specificity of 100%.24
Retrospective studies and case series have evaluated the use of prehospital ultrasound in the mass casualty setting, both for earthquakes and war zones. These reports use ultrasound as an adjunct to the simple triage and rapid treatment (START) protocol in the prehospital setting and as an adjunct to clinical care in the hospital setting.25-29 In a report on casualty management of victims of an earthquake in China, patient statuses were successfully upgraded from yellow to red based on the FAST.28 Whether or not ultrasound changes outcomes in this setting requires further study.
For a detailed review of additional diagnostic ultrasound applications for pediatric patients, including assessment for pneumonia, appendicitis, intussusception, pyloric stenosis, and pregnancy in the first trimester, see the January 2016 issue of Pediatric Emergency Medicine Practice titled, “Diagnostic Emergency Ultrasound: Assessment Techniques In The Pediatric Patient.”
For a detailed review of procedural ultrasound applications for pediatric patients, including the use of ultrasound guidance for peripheral line placement, bladder catheterization, lumbar puncture, and foreign body removal, see the June 2016 issue of Pediatric Emergency Medicine Practice titled, “Procedural Ultrasound In Pediatric Patients: Techniques And Tips For Accuracy And Safety.”
Evidence-based medicine requires a critical appraisal of the literature based upon study methodology and number of subjects. Not all references are equally robust. The findings of a large, prospective, randomized, and blinded trial should carry more weight than a case report.
To help the reader judge the strength of each reference, pertinent information about the study, such as the type of study and the number of patients in the study will be included in bold type following the references, where available.
Joshua Guttman, MD, FRCPC, FAAEM; Bret P. Nelson, MD, RDMS, FACEP
Delia L. Gold, MD; Thomas Mailhot, MD
July 15, 2019
August 14, 2022
4 AMA PRA Category 1 Credits.™ Specialty CME Credits: Included as part of the 4 credits, this CME activity is eligible for 4 Trauma CME credits, subject to your state and institutional approval.
Date of Original Release: July 15, 2019. Date of most recent review: June 15, 2019. Termination date: July 15, 2022.
Accreditation: EB Medicine is accredited by the Accreditation Council for Continuing Medical Education (ACCME) to provide continuing medical education for physicians. This activity has been planned and implemented in accordance with the accreditation requirements and policies of the ACCME.
Credit Designation: EB Medicine designates this enduring material for a maximum of 4 AMA PRA Category 1 Credits™. Physicians should claim only the credit commensurate with the extent of their participation in the activity.
Specialty CME: Included as part of the 4 credits, this CME activity is eligible for 4 Trauma CME credits, subject to your state and institutional requirements.
Needs Assessment: The need for this educational activity was determined by a survey of medical staff, including the editorial board of this publication; review of morbidity and mortality data from the CDC, AHA, NCHS, and ACEP; thorough review of current literature on the topic and practice gap assessment; and evaluation of prior activities for emergency physicians.
Target Audience: This enduring material is designed for emergency medicine physicians, physician assistants, nurse practitioners, and residents.
Goals: Upon completion of this activity, you should be able to: (1) demonstrate medical decision-making based on the strongest clinical evidence; (2) cost-effectively diagnose and treat the most critical presentations; and (3) describe the most common medicolegal pitfalls for each topic covered.
CME Objectives: Upon completion of this activity, you should be able to: (1) use the FAST and E-FAST examinations to assess pediatric patients with abdominal or chest trauma for conditions such as free fluid, pneumothorax, and hemothorax; (2) demonstrate diagnostic ultrasound techniques utilized to assess cardiac conditions, such as pericardial effusion, tamponade, and cardiac arrest, and assess left ventricular ejection fraction; and (3) utilize diagnostic ultrasound to assess for other pediatric conditions, including skull fractures, forearm fractures, and testicular torsion.
Discussion of Investigational Information: As part of the journal, faculty may be presenting investigational information about pharmaceutical products that is outside Food and Drug Administration–approved labeling. Information presented as part of this activity is intended solely as continuing medical education and is not intended to promote off-label use of any pharmaceutical product.
Faculty Disclosures: It is the policy of EB Medicine to ensure objectivity, balance, independence, transparency, and scientific rigor in all CME-sponsored educational activities. All faculty participating in the planning or implementation of a sponsored activity are expected to disclose to the audience any relevant financial relationships and to assist in resolving any conflict of interest that may arise from the relationship. In compliance with all ACCME Essentials, Standards, and Guidelines, all faculty for this CME activity were asked to complete a full disclosure statement. The information received is as follows: Dr. Guttman, Dr. Nelson, Dr. Gold, Dr. Mailhot, and their related parties report no relevant financial interest or other relationship with the manufacturer(s) of any commercial product(s) discussed in this educational presentation.
Commercial Support: This supplement to Pediatric Emergency Medicine Practice did not receive any commercial support.
Earning Credit: Read the PDF and complete the CME test online.
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