Performance of Intra-arrest Echocardiography: A Systematic Review.

Introduction: Intra-arrest transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) have been introduced in adult patients with cardiac arrest (CA). Whether the diagnostic performance of TTE or TEE is superior during resuscitation is unclear. We conducted a systematic review following PRISMA guidelines. Methods: We searched databases from PubMed, Embase, and Google Scholar and evaluated articles with intra-arrest TTE and TEE in adult patients with non-traumatic CA. Two authors independently screened and selected articles for inclusion; they then dual-extracted study characteristics and target conditions (pericardial effusion, aortic dissection, pulmonary embolism, myocardial infarction, hypovolemia, left ventricular dysfunction, and sonographic cardiac activity). We performed quality assessment using the Quality Assessment of Diagnostic Accuracy Studies Version 2 criteria. Results: A total of 27 studies were included: 14 studies with 2,145 patients assessed TTE; and 16 with 556 patients assessed TEE. A high risk of bias or applicability concerns in at least one domain was present in 20 studies (74%). Both TTE and TEE found positive findings in nearly one-half of the patients. The etiology of CA was identified in 13% (271/2,145), and intervention was performed in 38% (102/271) of patients in the TTE group. In patients who received TEE, the etiology was identified in 43% (239/556), and intervention was performed in 28% (68/239). In the TEE group, a higher incidence regarding the etiology of CA was observed, particularly for those with aortic dissection. However, the outcome of those with aortic dissection in the TEE group was poor. Conclusion: While TEE could identify more causes of CA than TTE, sonographic cardiac activity was reported much more in the TTE group. The impact of TTE and TEE on the return of spontaneous circulation and further survival was still inconclusive in the current dataset.

Ultrasound during Advanced Life Support-Help or Harm?

Ultrasound is used in cardiopulmonary resuscitation (CPR) and advanced life support (ALS). However, there is divergence between the recommendations of many emergency and critical care societies who support its use and the recommendations of many international resuscitation organizations who either recommend against its use or recommend it only in limited circumstances. Ultrasound offers potential benefits of detecting reversable causes of cardiac arrest, allowing specific interventions. However, it also risks interfering with ALS protocols and increasing unhelpful interventions. As with many interventions in ALS, the evidence base for ultrasound use is weak, and well-designed randomized trials are needed. This paper reviews the current theory and evidence for harms and benefits.

A feasibility study of a handmade ultrasound-guided phantom for paracentesis.

BACKGROUND: Simulation-based training is effective for ultrasound (US)-guided procedures. However, commercially developed simulators are costly. This study aims to evaluate the feasibility of a hand-made phantom for US-guided paracentesis. METHODS: We described the recipe to prepare an agar phantom. We collected the US performance data of 50 novices, including 22 postgraduate-year (PGY) residents and 28 undergraduate-year (UGY) students, who used the phantom for training, as well as 12 emergency residents with prior US-guided experience. We obtained the feedback after using the phantom with the Likert 5-point scale. The data were presented with medians and interquartile ranges (IQRs) and analyzed by the Wilcoxon rank sum test. RESULTS: While emergency residents demonstrated superior performance compared to trainees, all trainees exhibited acceptable proficiency (global rating of ≥ 3, 50/50 vs. 12/12, p = 1.000) and comparable needle steadiness [5 (5) vs. 5 (5), p = 0.223]. No significant difference in performance was observed between PGYs [5 (4-5)] and UGYs [5 (4-5), p = 0.825]. No significant differences were observed in terms of image stimulation, puncture texture, needle visualization, drainage simulation, and endurance of the phantom between emergency residents and trainees. However, experienced residents rated puncture texture and draining fluid as "neutral" (3/5 on the Likert scale). The cost of the paracentesis phantom is US$16.00 for at least 30 simulations, reducing it to US$6.00 without a container. CONCLUSIONS: The paracentesis phantom proves to be a practical and cost-effective training tool. It enables novices to acquire paracentesis skills, enhances their US proficiency, and boosts their confidence. Nevertheless, further investigation is needed to assess its long-term impact on clinical performance in real patients. TRIAL REGISTRATION: NCT04792203 at the ClinicalTrials.gov.

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.

The effect of point-of-care ultrasound on length of stay and mortality in patients with chest pain/dyspnea.

PURPOSE: This study aims to investigate the effects of point-of-care ultrasound (PoCUS) on length of stay (LOS) and mortality in hemodynamically stable patients with chest pain/dyspnea. MATERIALS AND METHODS: The prospective study was conducted from June 2020 to May 2021. A convenience sample of adult non-traumatic patients with chest pain/dyspnea was included and evaluated by PoCUS. The primary outcome was the relationship between the door-to-PoCUS time and LOS/mortality categorized by the ST-segment elevation (STE) and non-STE on the initial electrocardiogram. The diagnostic accuracy of PoCUS was computed, compared to the final diagnosis. RESULTS: A total of 465 patients were included. 3 of 18 patients with STE had unexpected cardiac tamponade and 1 had myocarditis with pulmonary edema. PoCUS had a minimal effect on LOS and mortality in patients with STE. In the non-STE group, the shorter door-to-PoCUS time was associated with a shorter LOS (coefficient, 1.26±0.47, p=0.008). After categorizing the timing of PoCUS as 30, 60, 90, and 120 minutes, PoCUS had a positive effect, especially when performed within 90 minutes of arrival, on LOS of less than 360 minutes (OR, 2.42, 95% CI, 1.61-3.64) and patient survival (OR, 3.32, 95% CI, 1.14-9.71). The overall diagnostic performance of PoCUS was 96.6% (95% CI, 94.9-98.2%), but lower efficacy occurred in pulmonary embolism and myocardial infarction. CONCLUSION: The use of PoCUS was associated with a shorter LOS and less mortality in patients with non-STE, especially when performed within 90 minutes of arrival. Although the effect on patients with STE was minimal, PoCUS played a role in discovering unexpected diagnoses.

Colonic Diverticulitis Location Affects the Diagnostic Accuracy of Point-of-Care Ultrasound: A Multicenter, 10-Year Study.

OBJECTIVE: Point-of-care ultrasound (PoCUS) has high sensitivity and specificity in diagnosing uncomplicated colonic diverticulitis in Western patients. Evidence regarding the accuracy of PoCUS in Asian patients in which diverticulitis frequently occurs in the right-side colon is lacking. This multicenter, 10-y study was aimed at evaluating the diagnostic accuracy of PoCUS in various locations of uncomplicated diverticulitis among Asians. METHODS: A convenience sample of patients with suspected colonic diverticulitis who had undergone computed tomography (CT) were eligible. Patients undergoing PoCUS before CT were included. The primary outcome was the diagnostic accuracy of PoCUS in the various locations, compared with the final diagnosis made by the expert physicians. The sensitivity, specificity, positive predictive value and negative predictive value were computed. The logistic regression model was used to investigate the possible factors related to the accuracy of PoCUS. RESULTS: A total of 326 patients were included. The overall accuracy of PoCUS was 92% (95% confidence interval [CI]: 89.1%-95.0%) and was lower in the cecum (84.3%, 95% CI: 77.8%-90.8%), compared with other locations (p < 0.0001). Nine of 10 false positives had the final diagnosis of appendicitis: 5 had an outpouching structure whose origin in the cecum could not be traced and 4 had elongated "diverticula." Moreover, body mass index was negatively associated with the accuracy of PoCUS in cecal diverticulitis (odds ratio: 0.79, 95% CI: 0.64-0.97) after adjusting for other covariates. CONCLUSION: Point-of-care ultrasound exhibits high diagnostic accuracy in diagnosing uncomplicated diverticulitis in the Asian population. However, the accuracy varies according to location, and was relatively low in the cecum.

The Effectiveness of Online-Only Blended Cardiopulmonary Resuscitation Training: Static-Group Comparison Study.

BACKGROUND: Basic life support (BLS) education is essential for improving bystander cardiopulmonary resuscitation (CPR) rates, but the imparting of such education faces obstacles during the outbreak of emerging infectious diseases, such as COVID-19. When face-to-face teaching is limited, distance learning-blended learning (BL) or an online-only model-is encouraged. However, evidence regarding the effect of online-only CPR training is scarce, and comparative studies on classroom-based BL (CBL) are lacking. While other strategies have recommended self-directed learning and deliberate practice to enhance CPR education, no previous studies have incorporated all of these instructional methods into a BLS course. OBJECTIVE: This study aimed to demonstrate a novel BLS training model-remote practice BL (RBL)-and compare its educational outcomes with those of the conventional CBL model. METHODS: A static-group comparison study was conducted. It included RBL and CBL courses that shared the same paradigm, comprising online lectures, a deliberate practice session with Little Anne quality CPR (QCPR) manikin feedback, and a final assessment session. In the main intervention, the RBL group was required to perform distant self-directed deliberate practice and complete the final assessment via an online video conference. Manikin-rated CPR scores were measured as the primary outcome; the number of retakes of the final examination was the secondary outcome. RESULTS: A total of 52 and 104 participants from the RBL and CBL groups, respectively, were eligible for data analysis. A comparison of the 2 groups revealed that there were more women in the RBL group than the CBL group (36/52, 69.2% vs 51/104, 49%, respectively; P=.02). After adjustment, there were no significant differences in scores for QCPR release (96.9 vs 96.4, respectively; P=.61), QCPR depth (99.2 vs 99.5, respectively; P=.27), or QCPR rate (94.9 vs 95.5, respectively; P=.83). The RBL group spent more days practicing before the final assessment (12.4 vs 8.9 days, respectively; P<.001) and also had a higher number of retakes (1.4 vs 1.1 times, respectively; P<.001). CONCLUSIONS: We developed a remote practice BL-based method for online-only distant BLS CPR training. In terms of CPR performance, using remote self-directed deliberate practice was not inferior to the conventional classroom-based instructor-led method, although it tended to take more time to achieve the same effect. TRIAL REGISTRATION: Not applicable.

Impact of Ultrasonography on Chest Compression Fraction and Survival in Patients with Out-of-hospital Cardiac Arrest.

INTRODUCTION: Whether ultrasonography (US) contributes to delays in chest compressions and hence a negative impact on survival is uncertain. In this study we aimed to investigate the impact of US on chest compression fraction (CCF) and patient survival. METHODS: We retrospectively analyzed video recordings of the resuscitation process in a convenience sample of adult patients with non-traumatic, out-of-hospital cardiac arrest. Patients receiving US once or more during resuscitation were categorized as the US group, while the patients who did not receive US were categorized as the non-US group. The primary outcome was CCF, and the secondary outcomes were the rates of return of spontaneous circulation (ROSC), survival to admission and discharge, and survival to discharge with a favorable neurological outcome between the two groups. We also evaluated the individual pause duration and the percentage of prolonged pauses associated with US. RESULTS: A total of 236 patients with 3,386 pauses were included. Of these patients, 190 received US and 284 pauses were related to US. Longer resuscitation duration was observed in the US group (median, 30.3 vs 9.7 minutes, P<.001). The US group had comparable CCF (93.0% vs 94.3%, P=0.29) with the non-US group. Although the non-US group had a better rate of ROSC (36% vs 52%, P=0.04), the rates of survival to admission (36% vs 48%, P=0.13), survival to discharge (11% vs 15%, P=0.37), and survival with favorable neurological outcome (5% vs 9%, P=0.23) did not differ between the two groups. The pause duration of pulse checks with US was longer than pulse checks alone (median, 8 vs 6 seconds, P=0.02). The percentage of prolonged pauses was similar between the two groups (16% vs 14%, P=0.49). CONCLUSION: When compared to the non-ultrasound group, patients receiving US had comparable chest compression fractions and rates of survival to admission and discharge, and survival to discharge with a favorable neurological outcome. The individual pause was lengthened related to US. However, patients without US had a shorter resuscitation duration and a better rate of ROSC. The trend toward poorer results in the US group was possibly due to confounding variables and nonprobability sampling. It should be better investigated in further randomized studies.

Effects of COVID-19 vaccine type on Guillain-Barré syndrome: Two cases and a literature review.

Guillain-Barré syndrome (GBS) is a rare but severe complication of COVID-19 vaccination. We report two cases of GBS following vaccination with the adenovirus vector vaccine ChAdOx1 nCoV-19 (Vaxzevria, AstraZeneca) and review the relevant literature. Relevant studies published between December 2020 and May 2022 including 881 patients with GBS were reviewed. GBS incidence and the need for mechanical ventilation were reported at a higher level among patients receiving Vaxzevria (n = 400). However, incidence cannot be accurately estimated from case reports. Thus, the true GBS rates following COVID-19 vaccination should be determined by population-based data.

Detecting Hydronephrosis Through Ultrasound Images Using State-of-the-Art Deep Learning Models.

The goal of this study was to assess the feasibility of three models for detecting hydronephrosis through ultrasound images using state-of-the-art deep learning algorithms. The diagnosis of hydronephrosis is challenging because of varying and non-specific presentations. With the characteristics of ready accessibility, no radiation exposure and repeated assessments, point-of-care ultrasound becomes a complementary diagnostic tool for hydronephrosis; however, inter-observer variability still exists after time-consuming training. Artificial intelligence has the potential to overcome the human limitations. A total of 3462 ultrasound frames for 97 patients with hydronephrosis confirmed by the expert nephrologists were included. One thousand six hundred twenty-eight ultrasound frames were also extracted from the 265 controls who had normal renal ultrasonography. We built three deep learning models based on U-Net, Res-UNet and UNet++ and compared their performance. We applied pre-processing techniques including wiping the background to lessen interference by YOLOv4 and standardizing image sizes. Also, post-processing techniques such as adding filter for filtering the small effusion areas were used. The Res-UNet algorithm had the best performance with an accuracy of 94.6% for moderate/severe hydronephrosis with substantial recall rate, specificity, precision, F1 measure and intersection over union. The Res-UNet algorithm has the best performance in detection of moderate/severe hydronephrosis. It would decrease variability among sonographers and improve efficiency under clinical conditions.

The effect of e-learning on point-of-care ultrasound education in novices.

BACKGROUND: Current studies assessed the learning efficacy of e-learning in ultrasound (US) training using questionnaires, or simulation in well-controlled conditions. This study investigates the effect of e-learning on the clinical US performance of the first postgraduate year (PGY-1) residents. METHODS: In this prospective observational study, we enrolled PGY-1 and second postgraduate year (PGY-2) residents. The e-learning was introduced on the first day and each PGY-1 was authorized to access the e-learning platform. The point-of-care ultrasound (PoCUS) curriculum for the focused assessment of sonography for trauma (FAST) was conducted on the 7th day for PGY-1 and the objective structured clinical examination (OSCE) followed. The PGY-2 received bedside one-to-one random learning before the study and did not have the authorization to access the e-learning. The FAST examinations performed by the PGY-1 and PGY-2 were collected on the 30th day. The clinical FAST performance was assessed by the instructor not involved in the curriculum and blinded to the use of e-learning, including numbers, image quality, and diagnostic accuracy between PGY-1 e-learning users, non-users, and the PGY-2. RESULTS: One hundred and seventy PGY-1 with 736 FAST examinations and 53 PGY-2 residents with 134 examinations were included. Seventy PGY-1 used e-learning with a median time spent of 13.2 mins (IQR, 6.5-21.1 mins) at the first access. The PGY-2 had more PoCUS experience than the PGY-1, however, the 70 e-learning users performed more FAST examinations than the PGY-2 (median [IQR], 4 [2-6] vs. 2 [1-3], p = 0.0004) and had better image quality than the PGY-2 (3 [3-3.2] vs. 3 [2.7-3], p = 0.044). There were no significant differences in the diagnostic accuracy between the PGY-1 and PGY-2. CONCLUSIONS: E-learning has a positive effect on US learning. The PGY-1 users had comparable performance with the PGY-2 and even better image acquisition although the PGY-2 had more PoCUS experience. TRIAL REGISTRATION: NCT03738033 at ClinicalTrials.gov.

RAPIDEST: A Framework for Obstructive Sleep Apnea Detection.

The traditional polysomnography (PSG) examination for Obstructive Sleep Apnea (OSA) diagnosis needs to measure several signals, such as EEG, ECG, EMG, EOG and the oxygen level in blood, of a patient who may have to wear many sensors during sleep. After the PSG examination, the Apnea-Hypopnea Index (AHI) is calculated based on the measured data to evaluate the severity of apnea and hypopnea for the patient. This process is obviously complicated and inconvenient. In this paper, we propose an AI-based framework, called RAre Pattern Identification and DEtection for Sleep-stage Transitions (RAPIDEST), to detect OSA based on the sequence of sleep stages from which a novel rarity score is defined to capture the unusualness of the sequence of sleep stages. More importantly, under this framework, we only need EEG signals, thus significantly simplifying the signal collection process and reducing the complexity of the severity determination of apnea and hypopnea. We have conducted extensive experiments to verify the relationship between the rarity score and AHI and demonstrate the effectiveness of our proposed approach.

The outcomes of right-sided and left-sided colonic diverticulitis following non-operative management: a systematic review and meta-analysis.

BACKGROUND: There is no sufficient overview of outcomes in right-sided and left-sided colonic diverticulitis (CD) following non-operative management. This systematic review was conducted to evaluate the recurrence/treatment failure in right-sided and left-sided CD. METHODS: A systematic review was conducted following PRISMA guidelines. MEDLINE, Embase, and Cochrane Library from inception to Dec 2021 were searched. The study characteristics, recurrence/treatment failure, and risk factors for recurrence/treatment failure were extracted. Proportional meta-analyses were performed to calculate the pooled recurrent/treatment failure rate of right-sided and left-sided CD using the random effect model. Logistic regression was applied for the factors associated with the recurrence/treatment failure. RESULTS: Thirty-eight studies with 10,129 patients were included, and only two studies comprised both sides of CD. None of the studies had a high risk of bias although significant heterogeneity existed. The pooled recurrence rate was 10% (95% CI 8-13%, I2 = 86%, p < 0.01) in right-sided and 20% (95% CI 16-24%, I2 = 92%, p < 0.01) in left-sided CD. For the uncomplicated CD, the pooled recurrence rate was 9% (95% CI 6-13%, I2 = 77%, p < 0.01) in right-sided and 15% (95% CI 8-27%, I2 = 97%, p < 0.01) in the left-sided. Age and gender were not associated with the recurrence of both sides. The treatment failure rate was 5% (95% CI 2-10%, I2 = 84%, p < 0.01) in right-sided and 4% (95% CI 2-7%, I2 = 80%, p < 0.01) in left-sided CD. The risk factors for recurrence and treatment failure were limited. CONCLUSION: Non-operative management is effective with low rates of recurrence and treatment failure for both right-sided and left-sided CD although left-sided exhibits a higher recurrence. The recurrence rates did not differ between patients receiving antibiotics or not in uncomplicated CD. Age and sex were not associated with the recurrence although other risk factors were dispersing. Further risk factors for recurrence and treatment failure would be investigated for precise clinical decision-making and individualized strategy.