In line with a remark in the AAP position statement, the ESPR believes non-radiologist point-of-care US should be limited to guiding specific interventions, such as line placement and suprapubic punctures, or to those studies that are performed to promptly answer specific diagnostic yes/no questions [
22]. This approach contrasts the comprehensive US examination performed by paediatric radiologists as an integrated part of an imaging work-up, including a detailed assessment of the actual region, with colour and spectral Doppler, elastography or intravenous contrast added as appropriate. Within Europe, the training should be in line with the European Training Curriculum for Radiology where, preferably for paediatric radiology, subspecialty training has been undertaken [
23,
24]. The question arises of which studies can be performed as non-radiologist point-of-care US after a limited period of training and supervision. All radiologists will have several anecdotal cases in which non-radiologist point-of-care US missed the diagnosis thus leading to a delay in the diagnosis and potential damage to the patient. However, this remains anecdotal as there are no studies into the true extent, if at all present, of this problem. Non-radiologist point-of-care US can be divided into five domains, as specified by the American College of Emergency Physicians, covering a wide range of indications (Table
1). Although this division into domains is useful, it does not prioritize which aspects should be taught to and performed by a non-radiologist. Using the Delphi Technique, an international team of members of the Paediatric Emergency Medicine POCUS Network (P2Network) determined which indications should be incorporated in its fellowship training (Table
2) [
22]. An almost overlapping list of indications can be created by combining the publications from the Society of Hospital Medicine and the Society for Academic Emergency Medicine (Table
3) [
15,
23]. Both these lists, however, go beyond a simple diagnostic yes/no question and require in-depth knowledge of clinical radiology and diagnostic and interventional US. An example is diagnosing appendicitis, which may indeed be straightforward to diagnose if the appendix is easy to visualise but, in daily practice, this is often difficult and can be challenging even for advanced radiology residents. A similar case can be made for the diagnosis of intussusception. In very straightforward cases, which meet all the clinical criteria for the diagnosis, it is a relatively simple diagnosis with well-known false-positive and false-negative findings. However, only about 30% of paediatric cases present with the classic clinical criteria, and the imaging findings are also used to decide the method of treatment; therefore, the use of non-radiologist point-of-care US could even lead to a delay in treatment [
24]. In several domains, including acute abdominal pain in children, age, symptoms and initial US findings will guide the paediatric radiologist to modify the technique, potentially assess other areas like the inguinal canal or the lung bases and pay attention to detail to reach a correct diagnosis. Therefore, in a classic clinical scenario, non-radiologist point-of-care US could also lead to additional costs and potentially delay the diagnostic/treatment process. With respect to interventional procedures, there has been a strong shift toward subspecialisation in this field, exemplified by abscess drainage, where, unless very superficial, the procedure not only requires a dedicated skill set but also a dedicated environment and interventional equipment. Both will not be readily available to paediatricians performing non-radiologist point-of-care US.
Table 1
American College of Emergency Physicians classification of non-radiologist point-of-care ultrasound (US) [
14]
Resuscitative | US used as directly related to an acute resuscitation |
Diagnostic | US used in an emergent diagnostic imaging capacity |
Symptom- or sign-based | US used in a clinical pathway based upon the patient’s symptom or sign (e.g., shortness of breath) |
Procedure guidance | US used as an aid to guide a procedure |
Therapeutic and monitoring | US used in therapeutics or in physiological monitoring |
Table 2
Non-radiologist point-of-care US applications to include in training as presented by the Paediatric Emergency Medicine by Delphi Technique POCUS Network (P2Network) [
22]
Round 1 | |
Identify free peritoneal fluid in trauma | 100 |
Identify non-traumatic pericardial effusion | 100 |
Identify pericardial effusion in trauma | 100 |
Identify haemothorax | 98 |
Identify pleural fluid/effusion | 98 |
Identify pneumothorax | 98 |
Identify cardiac standstill | 96 |
Abscess incision and drainage | 94 |
Identify abscess | 94 |
Central line placement | 91 |
Evaluate cardiac function | 88 |
Identify cellulitis | 88 |
Identify intussusception | 87 |
Identify intrauterine pregnancy | 85 |
Identify soft-tissue foreign body | 85 |
Assess bladder volume | 83 |
Identify lung consolidation | 83 |
Peripheral intravenous access | 81 |
Round 2 | |
Foreign body localizations and removal | 89 |
Identify pulmonary oedema | 84 |
Pericardiocentesis | 84 |
Table 3
Indications for non-radiologist point-of-care US and for paediatric radiologic studies based on the combined position statements of the Society of Hospital Medicine (SHM) and the Society for Academic Emergency Medicine (SAEP) [
15,
23]
Pulmonary | Pleural effusion Pneumothorax | Alveolar syndromes Interstitial syndromes |
Abdominal | Early pregnancy Free fluid Gallbladder—Cholelithiasis Bladder volume Organ size (liver, kidney, spleen) | Appendicitis Gallbladder – Cholecystitis Dilated pelvicalyceal systems (hydronephrosis) Intussusceptiona Pyloric stenosis |
Vascular | | DVT AAAb |
Musculoskeletal | Abscess Cellulitis Joint effusions | Foreign bodies Fracture |
Intervention | Arterial line placement Arthrocentesis CVC placement Lumbar puncture Paracentesis | Abscess drainagec |
Multisystemd | | |
Hypotension and shock | Cardiace Pulmonary Abdominal free fluid | DVT |
Resuscitation | Cardiac Pulmonary | |
Dyspnoea | Cardiac Pulmonary | DVT |
Acute renal failure | Renal Bladder Central venous pressure Pulmonary | |