Ultrasound Guidelines: Emergency, Point-of-Care, and Clinical Ultrasound Guidelines in Medicine

Dobutamine-induced alterations in internal carotid artery blood flow and cerebral blood flow in healthy adults

PURPOSE

Dobutamine, a sympathomimetic agent, is widely used clinically, influencing cardiac output, heart rate (HR), and blood pressure (BP), which may impact cerebral blood flow (CBF), critical for brain metabolism. However, the effects of dobutamine on CBF and internal carotid artery (ICA) blood flow remain unclear, with contradictory reported in both clinical and animal studies. It is necessary to investigate the effects of dobutamine on cervical and cerebral hemodynamics. This study aimed to evaluate the effects of dobutamine infusion on ICA blood flow and CBF, explore their relationship, and identify factors influencing CBF to facilitate timely monitoring in clinical practice.

METHODS

Forty-eight healthy volunteers underwent physiological assessment, ICA ultrasound, and brain magnetic resonance imaging (MRI) data before and after the administration of dobutamine. Paired t and Wilcoxon signed-rank tests were used to analyze changes, while logistic regression explored associations between hemodynamic factors and CBF.

RESULTS

Dobutamine infusion significantly increased HR, respiration rate, systolic BP (SBP), diastolic BP (DBP), and mean arterial pressure, while blood oxygen remained stable. Compared with those in the resting state, the peak systolic velocity (Vs), resistance index, pulsatility index, and systolic/diastolic ratio (S/D) increased, whereas end-diastolic velocity (Vd) decreased. ICA diameter and mean velocity showed no significant changes. CBF significantly decreased in the anterior and middle cerebral arteries. Logistic regression identified SBP, DBP, and S/D difference as key factors associated with CBF reduction.

CONCLUSIONS

Dobutamine altered ICA hemodynamics and reduced CBF in anterior and middle cerebral arteries. Real-time ICA ultrasound monitoring provides valuable guidance during clinical use.

Point-of-Care Ultrasound Infrastructure

Point-of-care ultrasound (POCUS) infrastructure is the underpinning of a well integrated POCUS program. In order to achieve its full potential and fully integrate into the health care system, a POCUS program requires a robust and resilient infrastructure. The essential components of POCUS infrastructure are hardware, software, and an informed, well-integrated governance structure. This infrastructure can be leveraged for clinical decision-making, education, research, credentialing, documentation, health record integration as well as quality assurance and improvement.

Review of Point-of-Care Diaphragmatic Ultrasound in Emergency Medicine: Background, Techniques, Achieving Competency, Research, and Recommendations

ABSTRACT

The diaphragm is the major muscle of inspiration accounting for approximately 70% of the inspired tidal volume. Point-of-care diaphragmatic ultrasound offers the ability to quantitatively assess diaphragmatic function, perform serial evaluations over time, and visualize structures above and below the diaphragm. Although interest in point-of-care ultrasound (POCUS) of the diaphragm is developing in the emergency medicine, assessment of the diaphragm and its function is not recognized as a core application by national organizations or expert guidelines. As a result, it is infrequently performed, and its potential value in research or clinical practice may not be fully appreciated. The purpose of this review is to describe the developmental aspects of the diaphragm as it pertains to POCUS, discuss the POCUS techniques for evaluating diaphragmatic function, address competency acquisition in this POCUS application, summarize relevant research in the ED, and provide a summary of recommendations for further research and clinical utilization of POCUS in diaphragm evaluation.

Contribution of point-of-care ultrasound in the prehospital management of patients with non-trauma acute dyspnea: a systematic review and meta-analysis

Acute dyspnea is a common symptom whose management is challenging in prehospital settings. Point-of-care ultrasound (POCUS) is increasingly accessible because of device miniaturization. To assess the contribution of POCUS in the prehospital management of patients with acute nontraumatic dyspnea, we performed a systematic review on nontrauma patients of any age managed in the prehospital setting for acute dyspnea and receiving a POCUS examination. We searched seven databases and gray literature for English-language studies published from January 1995 to November 2023. Two independent reviewers completed the study selection, data extraction, and risk of bias assessment. The primary outcome was the assessment of the contribution of POCUS to feasibility, diagnostic, therapeutic, prognosis, patient referral, and transport vector modification. Twenty-three studies were included. The risk of bias assessment identified 3 intermediate-risk, 18 serious-risk, and 2 critical-risk studies. Three studies reported moderate to excellent feasibility for lung POCUS, and three studies reported poor to mediocre feasibility for cardiac POCUS. The median duration of the POCUS examination was less than 5 minutes (six studies). POCUS improved diagnostic identification (seven studies). The diagnostic accuracy of POCUS was excellent for pneumothorax (sensitivity = 100%, specificity = 100%, two studies), very good for acute heart failure (sensitivity = 71-100%, specificity = 72-95%, eight studies), good for pneumonia (sensitivity = 88%, specificity = 59%, one study), and moderate for pleural effusion (sensitivity = 26-53%, specificity = 83-92%, two studies). Treatment was modified in 11 to 54% of the patients (seven studies). POCUS had no significant effect on patient prognosis (two studies). POCUS contributed to patient referrals and transport vectors in 51% (four studies) and 25% (three studies) of patients, respectively. The evidence supports the use of POCUS for managing acute nontraumatic dyspnea in the prehospital setting in terms of feasibility, overall diagnostic contribution, and, particularly, lung ultrasound for acute heart failure diagnosis. Moreover, POCUS seems to have a therapeutic contribution. There is not enough evidence supporting the use of POCUS for pneumonia, pleural effusion, pneumothorax, chronic obstructive pulmonary disease, or asthma exacerbation diagnosis, nor does it support prognostic, patient referral, and transport vector contribution. A high level of evidence is lacking and needed.

Rare Cause of Pediatric Abdominal Pain Diagnosed on Point of Care Ultrasound (POCUS)

An 11-year-old postmenarchal female presented to the pediatric emergency department (ED) with 2 days of periumbilical and right lower abdominal pain. Radiology-performed ultrasound (RADUS) did not visualize the appendix, and there was a plan for surgical consultation to decide between serial abdominal exams versus computed tomography (CT) scan. While awaiting consultation and to help further narrow the differential diagnosis, the emergency provider performed a point of care ultrasound (POCUS) of the urinary tract. This revealed several anomalies including a solitary left kidney with hydronephrosis, and a well-circumscribed, fluid-filled structure with mixed echogenicity posterior to the bladder and inferior to the uterus. Given these findings on POCUS, further imaging was pursued, including a RADUS of the pelvis followed by a magnetic resonance imaging (MRI) of the abdomen. Further imaging ultimately diagnosed a bicornuate uterus, septate vagina with hematocolpos and solitary left kidney consistent with Obstructed Hemivagina and Ipsilateral Renal Anomaly (OHVIRA) syndrome. This case is an illustration of how POCUS is an invaluable tool to narrow the differential diagnosis and guide advanced imaging or consultation for both common and rare causes of pediatric abdominal pain.

Ultrasound Administration and Reimbursement

One cannot successfully employ point-of-care ultrasound (POCUS) without a process to provide support and guidance. POCUS administration is a multifaceted topic that demands the utmost attention from those responsible for program implementation and long-term execution. This article delves into POCUS administration and is meant to serve as a guide for the practitioner seeking to start, maintain, or augment their POCUS program.

Common Ultrasound-Guided Procedures

Ultrasound guidance is fundamental to procedural safety and success. For many emergency department (ED) procedures, the use of ultrasound improves first-pass success rate, time-to-completion, and complication rate when compared with traditional landmark-based techniques. Once learned, the general principles of ultrasound guidance may be adapted across a broad range of bedside procedures.

Clinical Ultrasound in Obstetrics and Gynecology

Point-of-care ultrasound is a useful tool in the evaluation of women with pelvic complaints in the emergency department. Transabdominal and transvaginal approaches may be employed to assess a variety of obstetric or gynecologic pathologies.

Cardiac Point-Of-Care Ultrasound: An Emergency Medicine Review

Cardiac point-of-care ultrasound (POCUS) can make critical diagnoses and monitor the response to interventions. In contrast with consultative echocardiography, cardiac POCUS serves to answer a specific clinical question. This imaging modality can be used to evaluate for left ventricular systolic and diastolic dysfunction, pericardial effusion and tamponade, acute and chronic right ventricular dysfunction, valvular dysfunction, and cardiac activity in cardiac arrest.

POCUS literature primer: key papers on cardiac and lung POCUS

OBJECTIVE

Although point of care ultrasound (POCUS) use has become prevalent in medicine, clinicians may not be familiar with the evidence supporting its utility in patient care. The objective of this study is to identify the top five most influential papers published on the use of cardiac POCUS and lung POCUS in adult patients.

METHODS

A 14-member expert panel from the Canadian Association of Emergency Physicians (CAEP) Emergency Ultrasound Committee and the Canadian Ultrasound Fellowship Collaborative used a modified Delphi process. Panel members are ultrasound fellowship trained or equivalent, are engaged in POCUS scholarship, and are leaders in POCUS locally and nationally in Canada. The modified Delphi process consisted of three rounds of sequential surveys and discussion to achieve consensus on the top five most influential papers on cardiac POCUS and lung POCUS.

RESULTS

A total of 66 relevant papers on cardiac POCUS and 68 relevant papers on lung POCUS were nominated by the panel. There was 100% participation by the panel members in all three rounds of the modified Delphi process. At the end of this process, we identified the top five most influential papers on cardiac POCUS and lung POCUS. Papers include studies supporting the use of POCUS for accurately assessing left ventricular systolic function, diagnosing pericardial effusion, clarifying its test characteristics for pulmonary embolism, identifying pulmonary edema and pneumonia, as well as consensus statements on the use of cardiac and lung POCUS in clinical practice.

CONCLUSION

We have created a list of the top five influential papers on cardiac POCUS and lung POCUS as an evidence-based resource for trainees, clinicians, and researchers. This will help trainees and clinicians better understand how to use POCUS when scanning the heart and lungs, and it will also help researchers better understand where to direct their scholarly efforts with future research.

Current trends in emergency airway management: a clinical review

Airway management is a fundamental and complex process that involves a sequence of integrated tasks. Situations requiring emergency airway management may occur in the emergency department, intensive care units, and various other clinical spaces. A variety of challenges can arise during emergency airway preparation, intubation, and postintubation, which may result in significant complications for patients. Therefore, many countries are establishing step-by-step systemization and detailed guidelines and/or updating their content based on the latest research. This clinical review introduces the current trends in emergency airway management, such as emergency airway management algorithms, comparison of video and direct laryngoscopy, rapid sequence intubation, pediatric airway management, prehospital airway management, surgical airway management, and airway management education.

Revolutionizing Bladder Health: Artificial-Intelligence-Powered Automatic Measurement of Bladder Volume Using Two-Dimensional Ultrasound

INTRODUCTION

Measuring elevated post-void residual volume is important for diagnosing urinary outflow tract obstruction and cauda equina syndrome. Catheter placement is exact but painful, invasive, and may cause infection, whereas an ultrasound is accurate, painless, and safe.

AIM

The purpose of this single-center study is to evaluate the accuracy of a module for artificial-intelligence (AI)-based fully automated bladder volume (BV) prospective measurement using two-dimensional ultrasound images, as compared with manual measurement by expert sonographers.

METHODS

Pairs of transverse and longitudinal bladder images were obtained from patients evaluated in an urgent care clinic. The scans were prospectively analyzed by the automated module using the prolate ellipsoid method. The same examinations were manually measured by a blinded expert sonographer. The two methods were compared using the Pearson correlation, kappa coefficients, and the Bland-Altman method.

RESULTS

A total of 111 pairs of transverse and longitudinal views were included. A very strong correlation was found between the manual BV measurements and the AI-based module with r = 0.97 [95% CI: 0.96-0.98]. The specificity and sensitivity for the diagnosis of an elevated post-void residual volume using a threshold ≥200 mL were 1.00 and 0.82, respectively. An almost-perfect agreement between manual and automated methods was obtained (kappa = 0.85). Perfect reproducibility was found for both inter- and intra-observer agreements.

CONCLUSION

This AI-based module provides an accurate automated measurement of the BV based on ultrasound images. This novel method demonstrates a very strong correlation with the gold standard, making it a potentially valuable decision-support tool for non-experts in acute settings.

Pediatric ultrasound practice in Italy: an exploratory survey

BACKGROUND

The aim of this exploratory survey is to describe the current state of US (ultrasound) technique across different pediatric settings nationwide.

METHODS

A questionnaire was emailed to all members of the Italian Society of Pediatrics, including pediatric residents. The survey was open from December 2021 to March 2022.

RESULTS

There were 1098 respondents. Seven hundred and seven pediatricians (84.1%) reported any use of US, while 51 (44.3%) residents denied it. The majority of participants (n = 956, 87.1%) reported to have a US machine available within the department, mostly cart-based (n = 516, 66.9%) and provided from 1 to 5 years prior to the survey (n = 330, 42.8%). Lung and neonatal cerebral regions were the most frequently scanned (n = 289, 18.7% and n = 218, 14.1%, respectively). The suspicion of pneumonia or respiratory distress represented the main reasons for performing US in emergency room (n = 390, 78% and n = 330, 66%, respectively). The majority of family pediatricians reported to scan lung and kidney/urinary tract regions (n = 30, 16.9%, and n = 23,12.9%, respectively). Regarding US training, the majority of respondents (n = 358, 34.6%) declared an experience-based education, with a deficient certification enabling the use of US in 71.6% (n = 552) of cases. The most common barriers included the lack of a well-defined training program (n = 627, 57.1%), unavailability of the US machine (n = 196, 17.9%) and legal responsibility concern (n = 175, 15.9%).

CONCLUSIONS

Despite the growing interest on pediatric US nationally, significant barriers still limit widespread adoption. These obstacles may be addressed through the dissemination of a specific US education plan and providing additional resources.

Incorporating implementation science principles into curricular design

Implementation science (IS) is an approach focused on increasing the application of evidence-based health interventions into practice, through purposive and thoughtful planning to maximize uptake, scalability, and sustainability. Many of these principles can be readily applied to medical education, to help augment traditional approaches to curriculum design. In this paper, we summarize key components of IS with an emphasis on application to the medical educator.

Best Practices for Point of Care Ultrasound: An Interdisciplinary Expert Consensus

Despite the growing use of point of care ultrasound (POCUS) in contemporary medical practice and the existence of clinical guidelines addressing its specific applications, there remains a lack of standardization and agreement on optimal practices for several areas of POCUS use. The Society of Point of Care Ultrasound (SPOCUS) formed a working group in 2022 to establish a set of recommended best practices for POCUS, applicable to clinicians regardless of their training, specialty, resource setting, or scope of practice. Using a three-round modified Delphi process, a multi-disciplinary panel of 22 POCUS experts based in the United States reached consensus on 57 statements in domains including: (1) The definition and clinical role of POCUS; (2) Training pathways; (3) Credentialing; (4) Cleaning and maintenance of POCUS devices; (5) Consent and education; (6) Security, storage, and sharing of POCUS studies; (7) Uploading, archiving, and reviewing POCUS studies; and (8) Documenting POCUS studies. The consensus statements are provided here. While not intended to establish a standard of care or supersede more targeted guidelines, this document may serve as a useful baseline to guide clinicians, leaders, and systems considering initiation or enhancement of POCUS programs.

Blood or Fat? Differentiating Hemopericardium versus Epicardial Fat Using Focused Cardiac Ultrasound

Basic point-of-care ultrasound of the heart-also known as Focused Cardiac Ultrasound (FoCUS)-has emerged as a powerful bedside tool to narrow the differential diagnosis of causes of hypotension. The list of causes of hypotension that a FoCUS provider is expected to be able to recognize includes a compressive pericardial effusion due to hemopericardium (blood in the pericardial sac). But hemopericardium can be difficult to distinguish from a more common condition that is not immediately life-threatening: epicardial fat. This paper reviews illustrative images of both epicardial fat and hemopericardium to provide practice guidance to the FoCUS user on how to differentiate these two phenomena.

Diagnostic performance of ultrasound in acute cholecystitis: a systematic review and meta-analysis

BACKGROUND

An updated overview of ultrasound (US) for diagnosis of acute cholecystitis (AC) remains lacking. This systematic review was conducted to evaluate the diagnostic performance of US for AC.

METHODS

A systematic review was conducted following PRISMA guidelines. We meticulously screened articles from MEDLINE, Embase, and the Cochrane Library, spanning from inception to August 2023. We employed the search strategy combining the keywords "bedside US", "emergency US" or "point-of-care US" with "AC". Two reviewers independently screened the titles and abstracts of the retrieved articles to identify suitable studies. The inclusion criteria encompassed articles investigating the diagnostic performance of US for AC. Data regarding diagnostic performance, sonographers, and sonographic findings including the presence of gallstone, gallbladder (GB) wall thickness, peri-GB fluid, or sonographic Murphy sign were extracted, and a meta-analysis was executed. Case reports, editorials, and review articles were excluded, as well as studies focused on acalculous cholecystitis. The study quality was assessed with the Quality Assessment of Diagnostic Accuracy Studies-2 (QUADAS-2) tool.

RESULTS

Forty studies with 8,652 patients were included. The majority of studies had a low risk of bias and applicability concerns. US had a pooled sensitivity of 71% (95% CI, 69-72%), a specificity of 85% (95% CI, 84-86%), and an accuracy of 0.83 (95% CI, 0.82-0.83) for the diagnosis of AC. The pooled sensitivity and specificity were 71% (95% CI, 67-74%) and 92% (95% CI, 90-93%) performed by emergency physicians (EPs), 79% (95% CI, 71-85%) and 76% (95% CI, 69-81%) performed by surgeons, and 68% (95% CI 66-71%) and 87% (95% CI, 86-88%) performed by radiologists, respectively. There were no statistically significant differences among the three groups.

CONCLUSION

US is a good imaging modality for the diagnosis of AC. EP-performed US has a similar diagnostic performance to radiologist-performed US. Further investigations would be needed to investigate the impact of US on expediting the management process and improving patient-centered outcomes.