Variation of availability and frequency of emergency physician-performed ultrasonography between adult and pediatric patients in the academic emergency department in Korea

Impact of Insurance Benefits and Education on Point-of-Care Ultrasound Use in a Single Emergency Department: An Interrupted Time Series Analysis

Background and Objectives: Point-of-care ultrasound (POCUS) is a useful tool that helps clinicians properly treat patients in emergency department (ED). This study aimed to evaluate the impact of specific interventions on the use of POCUS in the ED. Materials and Methods: This retrospective study used an interrupted time series analysis to assess how interventions changed the use of POCUS in the emergency department of a tertiary medical institute in South Korea from October 2016 to February 2021. We chose two main interventions—expansion of benefit coverage of the National Health Insurance (NHI) for emergency ultrasound (EUS) and annual ultrasound educational workshops. The primary variable was the EUS rate, defined as the number of EUS scans per 1000 eligible patients per month. We compared the level and slope of EUS rates before and after interventions. Results: A total of 5188 scanned records were included. Before interventions, the EUS rate had increased gradually. After interventions, except for the first workshop, the EUS rate immediately increased significantly (p < 0.05). The difference in the EUS rate according to the expansion of the NHI was estimated to be the largest (p < 0.001). However, the change in slope significantly decreased after the third workshop during the coronavirus disease 2019 pandemic (p = 0.004). The EUS rate increased significantly in the presence of physicians participating in intensive POCUS training (p < 0.001). Conclusion: This study found that expansion of insurance coverage for EUS and ultrasound education led to a significant and immediate increase in the use of POCUS, suggesting that POCUS use can be increased by improving education and insurance benefits.

Assessing the validity of two-dimensional carotid ultrasound to detect the presence and absence of a pulse

BACKGROUND

Traditional assessment of return of cardiac output in cardiac arrest by manual palpation has poor accuracy. Point of care ultrasound of a major artery has been suggested as an alternative. We conducted a diagnostic accuracy study of two-dimensional carotid ultrasound to detect the presence or absence of a pulse, using cardiopulmonary bypass patients for pulse and pulseless states.

METHODS

A cross-sectional multi-patient, multi-reader repeated measures diagnostic study was conducted. For patients undergoing routine cardiopulmonary bypass, a portable ultrasound was used to record four 10-s videos the common carotid artery, three aimed for a pulse in high (>90 mmHg), medium (70-90 mmHg) and low (<70 mmHg) systolic blood pressure (SBP) ranges, and a pulseless video was recorded on cardiopulmonary bypass. Critical care physicians viewed the videos and were asked to nominate within 10 s if a pulse was present. True pulse-status was determined via the arterial-line waveform.

RESULTS

Twenty-three patients had all four videos collected. Median patient age was 64 (IQR 14), sixteen were male (70%) and median BMI was 27. The median SBP in high-, medium- and low-SBP groups were 120 mmHg, 83 mmHg and 69 mmHg respectively. Forty-six physicians reviewed a subset of 24 videos. Overall sensitivity was 0.91 (95% confidence interval 0.89-0.93) and specificity 0.90 (95% CI 0.86-0.93). Sensitivity was highest in the high-SBP group (0.96, 95% CI 0.93-0.98) and lowest in the low-SBP group (0.83, 95% CI 0.78-0.87).

CONCLUSION

2D ultrasound of the common carotid artery is both sensitive and specific for detection of the presence or absence of a pulse.

Point-of-Care Ultrasound Could Streamline the Emergency Department Workflow of Clinically Nonspecific Intussusception

OBJECTIVES

The aim of this study was to evaluate whether point-of-care ultrasound (POCUS) for intussusception screening streamlines the workflow of clinically nonspecific intussusception (CNI), an intussusception presenting with only 1 manifestation of the classic triad, and/or vomiting.

METHODS

We reviewed 274 consecutive children with intussusception, aged 6 years or younger, who visited a tertiary care hospital emergency department between May 2012 and April 2016. This period was dichotomized by May 2014 (the "PRE" and "POST" groups), starting point of implementation of the POCUS protocol for intussusception screening. All children with CNI who had positive results on or forwent POCUS underwent radiologist-performed ultrasound (US). We measured and compared emergency department length of stay (EDLOS), the sum of door-to-reduction and observation times, and the frequency of POCUS and positive US results between the 2 groups.

RESULTS

Of 160 children with CNI, 93 visited the emergency department since May 2014. The POST group showed a shorter median EDLOS (856 vs 630 minutes, P < 0.001), door-to-reduction time (137 vs 111 minutes, P = 0.002), and observation time (700 vs 532 minutes, P < 0.001). The POST group had a higher frequency of POCUS (12% vs 60%, P < 0.001) with positive US results (33% vs 59%, P < 0.001). The PRE group had a higher frequency of severe bowel edema (16% vs 1%, P < 0.001). No significant differences were found in the severity, recurrence, admission, and surgery. One child had a false-negative result on POCUS.

CONCLUSIONS

Point-of-care ultrasound could streamline the workflow of CNI via decrease in EDLOS and unnecessary referrals for US.

Diagnostic value of a power Doppler ultrasound-based malignancy index for differentiating malignant and benign solid breast lesions

BACKGROUND

Power Doppler ultrasound (PDUS) can provide useful information regarding the vascularity of breast lesions. The aim of this study was to investigate the diagnostic performance of a new PDUS-driven malignancy index in differentiating between malignant and benign causes of solid breast lesions.

MATERIALS AND METHODS

Patients with solid breast lesions were enrolled consecutively and evaluated first by PDUS and subsequently by histopathologic assessment after undergoing surgical biopsy. A custom-made software was used to extract data from images for calculating malignancy index formula.

RESULTS

A total of 87 patients with solid breast lesions were enrolled. Histopathologic evaluation identified 49 patients as benign and 38 patients as malignant. Malignancy index was significantly higher in the malignant group as compared to benign tumors (6.31 vs 0.30,P < 0.001). Area under the receiver operating characteristics (ROC) curve (AUC) was 0.98 (95% confidence interval (CI) 0.95-1.00). According to the ROC curve analysis, the cut-off point of 1.23 for malignancy index had a sensitivity and specificity of 94.7% (95% CI 82.2-99.3) and 94.0% (95% CI 83.1-98.7), respectively.

CONCLUSION

Comparing with the histopathologic evaluation as the gold standard for diagnosing breast lesions, PDUS-driven malignancy index was shown to have a high discriminative performance in identifying malignant lesions with high sensitivity, specificity, and diagnostic accuracy. The noninvasive nature of PDUS is an important advantage that could prevent unnecessary biopsies.

Point-of-care ultrasound in primary care: a systematic review of generalist performed point-of-care ultrasound in unselected populations

BACKGROUND

Both the interest and actual extent of use of point-of-care ultrasound, PoCUS, among general practitioners or family physicians are increasing and training is also increasingly implemented in residency programs. However, the amount of research within the field is still rather limited compared to what is seen within other specialties in which it has become more established, such as in the specialty of emergency medicine. An assumption is made that what is relevant for emergency medicine physicians and their populations is also relevant to the general practitioner, as both groups are generalists working in unselected populations. This systematic review aims to examine the extent of use and to identify clinical studies on the use of PoCUS by either general practitioners or emergency physicians on indications that are relevant for the former, both in their daily practice and in out-of-hours services.

METHODS

Systematic searches were done in PubMed/MEDLINE using terms related to general practice, emergency medicine, and ultrasound.

RESULTS

On the extent of use, we identified 19 articles, as well as 26 meta-analyses and 168 primary studies on the clinical use of PoCUS. We found variable, but generally low, use among general practitioners, while it seems to be thoroughly established in emergency medicine in North America, and increasingly also in the rest of the world. In terms of clinical studies, most were on diagnostic accuracy, and most organ systems were studied; the heart, lungs/thorax, vessels, abdominal and pelvic organs, obstetric ultrasound, the eye, soft tissue, and the musculoskeletal system. The studies found in general either high sensitivity or high specificity for the particular test studied, and in some cases high total accuracy and superiority to other established diagnostic imaging modalities. PoCUS also showed faster time to diagnosis and change in management in some studies.

CONCLUSION

Our review shows that generalists can, given a certain level of pre-test probability, safely use PoCUS in a wide range of clinical settings to aid diagnosis and better the care of their patients.

A Feasibility Study of Smartphone-Based Telesonography for Evaluating Cardiac Dynamic Function and Diagnosing Acute Appendicitis with Control of the Image Quality of the Transmitted Videos

Our aim was to prove the feasibility of the remote interpretation of real-time transmitted ultrasound videos of dynamic and static organs using a smartphone with control of the image quality given a limited internet connection speed. For this study, 100 cases of echocardiography videos (dynamic organ)-50 with an ejection fraction (EF) of ≥50 s and 50 with EF <50 %-and 100 cases of suspected pediatric appendicitis (static organ)-50 with signs of acute appendicitis and 50 with no findings of appendicitis-were consecutively selected. Twelve reviewers reviewed the original videos using the liquid crystal display (LCD) monitor of an ultrasound machine and using a smartphone, to which the images were transmitted from the ultrasound machine. The resolution of the transmitted echocardiography videos was reduced by approximately 20 % to increase the frame rate of transmission given the limited internet speed. The differences in diagnostic performance between the two devices when evaluating left ventricular (LV) systolic function by measuring the EF and when evaluating the presence of acute appendicitis were investigated using a five-point Likert scale. The average areas under the receiver operating characteristic curves for each reviewer's interpretations using the LCD monitor and smartphone were respectively 0.968 (0.949-0.986) and 0.963 (0.945-0.982) (P = 0.548) for echocardiography and 0.972 (0.954-0.989) and 0.966 (0.947-0.984) (P = 0.175) for abdominal ultrasonography. We confirmed the feasibility of remotely interpreting ultrasound images using smartphones, specifically for evaluating LV function and diagnosing pediatric acute appendicitis; the images were transferred from the ultrasound machine using image quality-controlled telesonography.

The reliability of carotid ultrasound in determining the return of pulsatile flow: A pilot study

Manual palpation of pulses is unreliable in detecting pulsatile flow in human participants, complicating the assessment of return of spontaneous circulation after cardiac arrest. Ultrasound may offer an alternative. This study's objective was to investigate whether return of pulsatile flow in humans can be reliably assessed by common carotid artery ultrasound. We conducted a single-blinded randomised study of common carotid artery ultrasound using 20 cardiopulmonary bypass patients to model the return of pulsatile flow. Synchronised time-stamped videos of radial artery invasive blood pressure and 10 two-dimensional or 10 colour Doppler ultrasounds were recorded. Three independent reviewers recorded the timestamp where they considered pulsatile flow was first visible on ultrasound. Ultrasound times were compared to the onset of arterial line pulsatile flow and reliability assessed by intraclass correlation coefficient. The median difference between radial artery and ultrasound flow time (interquartile range (range)) was 24 seconds (5-40 (0-93)) for two-dimensional and 5 seconds (2-17 (-28 to 188)) for colour Doppler. The intraclass correlation coefficient for two-dimensional ultrasound was 0.86 (95%CI 0.63-0.96) and 0.32 (95%CI -0.01 to 0.71) for colour Doppler. The median (interquartile range (range)) mean arterial pressure where ultrasound flow occurred for two-dimensional ultrasound was 62 mmHg (49-74 (33-82)) and 56 mmHg (52-73 (43-83)) for colour Doppler. In our pilot study, two-dimensional ultrasound was reliable in detecting the return of pulsatile flow. Colour Doppler detected pulsatile flow earlier and at lower mean arterial pressure but was not reliable, although a larger study is needed to determine colour Doppler's utility.

Comparison of internal jugular vein dilation between Valsalva maneuver and proximal internal jugular vein compression

Objective

The Valsalva maneuver is recognized as an effective method to dilate the internal jugular vein (IJV). However, this maneuver cannot be performed in many cases, such as children and unconscious patients. The aim of this study was to evaluate the effectiveness of proximal IJV compression, which can easily be performed, regardless of patient cooperation.

Methods

Healthy adult volunteers were recruited from tertiary hospital employees. Basic anatomic and physiologic data were collected. The subjects lay down as if they were undergoing IJV catheter insertion, in the supine position with their necks turned 30 degrees to the left. The main outcome was the cross-sectional area (CSA) of the distal IJV as measured by ultrasound in four stages. The first stage was sham without any maneuver. The second was Valsalva maneuver, the third was digital IJV compression, and the fourth was digital compression accompanied by simultaneous Valsalva maneuver.

Results

A total of 41 volunteers were enrolled. Twenty-six (63.41%) were male with an average age of 28.15±2.85 years. Mean height was 170.74±8.66 cm and mean neck circumference was 35.28±3.87 cm. The mean CSA-IJV was 1.06±0.36 cm² without any maneuver. It increased to 1.34±0.45 cm² with Valsalva maneuver (P<0.001), to 1.26±0.41 cm² with digital compression (P<0.001), and to 1.41±0.47 cm² with the two maneuvers combined (P=0.01).

Conclusion

Digital proximal IJV compression effectively dilates the distal IJV. When performed simultaneously with the Valsalva maneuver, the effect was enhanced.

Clinical application of real-time tele-ultrasonography in diagnosing pediatric acute appendicitis in the ED

PURPOSE

We investigated the effectiveness of tele-mentored ultrasonography between emergency medicine (EM) residents and remote experts in diagnosing acute appendicitis.

METHODS

This prospective observational study was performed in an academic emergency department. Beginning in June 2014, the EM residents performed the initial ultrasonography for suspected pediatric acute appendicitis; then, the remote experts observed/mentored the residents' practice using the tele-ultrasonography system; and finally, an onsite expert verified the diagnosis. The diagnostic confidence of each examiner (resident, remote expert, and onsite expert) was rated on a 5-point Likert scale. The appendix identification rate and the diagnostic values; sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) for each type of examination were calculated.

RESULTS

A total of 115 pediatric cases with suspected acute appendicitis, including 36 with pathology-confirmed acute appendicitis, between June 2014 and February 2015 were enrolled in this study. In 9 of the 115 (7.8%) cases, a non-appendicitis diagnosis was determined in the absence of the successful identification of a normal appendix upon resident examination. Of these, seven appendices were identified upon expert tele-ultrasonography. The diagnostic values for expert tele-ultrasonography were higher (sensitivity: 1.000, specificity: 0.975, PPV: 0.947, NPV: 1.000) than those for resident-performed ultrasonography (sensitivity: 0.917, specificity: 0.899, PPV: 0.805, NPV: 0.959) and similar to those for onsite expert-performed ultrasonography (sensitivity: 1.000, specificity: 0.987, PPV: 0.973, NPV: 1.000).

CONCLUSION

Tele-ultrasonography with tele-mentoring between EM residents and experienced mentors was effectively applied in diagnosing pediatric acute appendicitis in an emergency clinical setting.