A review of diagnostic accuracy and clinical impact from the focused use of perioperative ultrasound

A Soft-Reference Breast Ultrasound Image Quality Assessment Method That Considers the Local Lesion Area

The quality of breast ultrasound images has a significant impact on the accuracy of disease diagnosis. Existing image quality assessment (IQA) methods usually use pixel-level feature statistical methods or end-to-end deep learning methods, which focus on the global image quality but ignore the image quality of the lesion region. However, in clinical practice, doctors' evaluation of ultrasound image quality relies more on the local area of the lesion, which determines the diagnostic value of ultrasound images. In this study, a global-local integrated IQA framework for breast ultrasound images was proposed to learn doctors' clinical evaluation standards. In this study, 1285 breast ultrasound images were collected and scored by experienced doctors. After being classified as either images with lesions or images without lesions, they were evaluated using soft-reference IQA or bilinear CNN IQA, respectively. Experiments showed that for ultrasound images with lesions, our proposed soft-reference IQA achieved PLCC 0.8418 with doctors' annotation, while the existing end-to-end deep learning method that did not consider the local lesion features only achieved PLCC 0.6606. Due to the accuracy improvement for the images with lesions, our proposed global-local integrated IQA framework had better performance in the IQA task than the existing end-to-end deep learning method, with PLCC improving from 0.8306 to 0.8851.

Competence of anesthesiology residents following a longitudinal point-of-care ultrasound curriculum

PURPOSE

Point-of-care ultrasound (POCUS) facilitates diagnostic, procedural, and resuscitative applications in anesthesiology. Structured POCUS curricula improve learner satisfaction, test scores, and clinical management, but the learning curve towards competency and retention of skills over time remain unknown.

METHODS

We conducted a prospective observational study to determine when anesthesiology trainees enrolled in a POCUS curriculum achieve competency in POCUS skills. We also investigated the learning curve of trainees' competency using a POCUS-specific competency-based medical education assessment. The structured, longitudinal POCUS curriculum included online lectures, journal articles, live model scanning sessions, video review of cases, and a portfolio of supervised scans. Point-of-care ultrasound scanning sessions on standardized patients were conducted in the simulation lab for 2.5 hr a week and each resident completed eight sessions (20 hr) per academic year. At each scanning session, timed image acquisition scores were collected and POCUS skills entrustment scale evaluations were conducted. The primary outcome was the number of supervised scans and sessions required to achieve a mean entrustment score of 4 ("may use independently"). Secondary outcomes included image acquisition scores and retention of skills after six months.

RESULTS

The mean (standard deviation) number of supervised scans required for trainees (n = 29) to reach a mean entrustment score of ≥ 4 was 36 (10) scans over nine sessions for rescue echo. A mean entrustment score of ≥ 4 was observed for lung ultrasound after a mean (SD) of 8 (3) scans over two sessions.

CONCLUSIONS

Our study shows that anesthesiology residents can achieve competence in rescue echo and lung ultrasound through participation in a structured, longitudinal POCUS curriculum, and outlines the learning curve for progression towards competency.

A Comparison of Lung Ultrasound and Computed Tomography in the Diagnosis of Patients with COVID-19: A Systematic Review and Meta-Analysis

Background Lung ultrasound (LUS) and computed tomography (CT) can both be used for diagnosis of interstitial pneumonia caused by coronavirus disease 2019 (COVID-19), but the agreement between LUS and CT is unknown. Purpose to compare the agreement of LUS and CT in the diagnosis of interstitial pneumonia caused by COVID-19. Materials and Methods We searched PubMed, Cochrane library, Embase, Chinese Biomedicine Literature, and WHO COVID-19 databases to identify studies that compared LUS with CT in the diagnosis of interstitial pneumonia caused by COVID-19. We calculated the pooled overall, positive and negative percent agreements, diagnostic odds ratio (DOR) and the area under the standard receiver operating curve (SROC) for LUS in the diagnosis of COVID-19 compared with CT. Results We identified 1896 records, of which nine studies involving 531 patients were finally included. The pooled overall, positive and negative percentage agreements of LUS for the diagnosis of interstitial pneumonia caused by COVID-19 compared with CT were 81% (95% confidence interval [CI] 43–99%), 96% (95% CI, 80–99%, I² = 92.15%) and 80% (95%CI, 60–92%, I² = 92.85%), respectively. DOR was 37.41 (95% CI, 9.43–148.49, I² = 63.9%), and the area under the SROC curve was 0.94 (95% CI, 0.92–0.96). The quality of evidence for both specificity and sensitivity was low because of heterogeneity and risk of bias. Conclusion The level of diagnostic agreement between LUS and CT in the diagnosis of interstitial pneumonia caused by COVID-19 is high. LUS can be therefore considered as an equally accurate alternative for CT in situations where molecular tests are not available.

Simplified Algorithm for Evaluation of Perioperative Hypoxia and Hypotension (SALVATION): A Practical Echo-guided Approach Proposal

Despite the valuable use of modern applications of perioperative ultrasound across multiple disciplines, there have been limitations to its implementation, restricting its impact on patient-based clinical outcomes. Point-of-care ultrasound evaluation of hypoxia and hypotension is an important tool to assess the underlying undifferentiated etiologies in a timely manner. However, there is a lack of consensus on the formal role of ultrasound during evaluation of perioperative hypoxia or hypotension. The previous ultrasound algorithms have adopted a complex technique that possibly ignore the pathophysiologic mechanisms underlying the conditions presenting in a similar fashion. The authors here propose a simple, sequential and focused multiorgan approach, applicable for the evaluation of perioperative hypotension and hypoxia in emergency scenarios. The authors believe this approach will enhance the care provided in the postanesthesia care unit, operating room, and intensive care unit.

Perioperative echocardiography-guided hemodynamic therapy in high-risk patients: a practical expert approach of hemodynamically focused echocardiography

The number of high-risk patients undergoing surgery is growing. To maintain adequate hemodynamic functioning as well as oxygen delivery to the vital organs (DO2) amongst this patient population, a rapid assessment of cardiac functioning is essential for the anesthesiologist. Pinpointing any underlying cardiovascular pathophysiology can be decisive to guide interventions in the intraoperative setting. Various techniques are available to monitor the hemodynamic status of the patient, however due to intrinsic limitations, many of these methods may not be able to directly identify the underlying cause of cardiovascular impairment. Hemodynamic focused echocardiography, as a rapid diagnostic method, offers an excellent opportunity to examine signs of filling impairment, cardiac preload, myocardial contractility and the function of the heart valves. We thus propose a 6-step-echocardiographic approach to assess high-risk patients in order to improve and maintain perioperative DO2. The summary of all echocardiographic based findings allows a differentiated assessment of the patient's cardiovascular function and can thus help guide a (patho)physiological-orientated and individualized hemodynamic therapy.

[Perioperative optimization using hemodynamically focused echocardiography in high-risk patients-A practice guide]

BACKGROUND

The number of high-risk patients undergoing surgery is steadily increasing. In order to maintain and, if necessary, optimize perioperative hemodynamics as well as the oxygen supply to the organs (DO₂) in this patient population, a timely assessment of cardiac function and the underlying pathophysiological causes of hemodynamic instability is essential for the anesthesiologist. A variety of hemodynamic monitoring procedures are available for this purpose; however, due to method-immanent limitations they are often not able to directly identify the underlying cause of cardiovascular impairment.

OBJECTIVE

To present a stepwise algorithm for a perioperative echocardiography-based hemodynamic optimization in noncardiac surgery high-risk patients. In this context, echocardiography on demand according to international guidelines can be performed under certain conditions (hemodynamic instability, nonresponse to hemodynamic treatment) as well as in the context of a planned intraoperative procedure, mostly as a transesophageal echocardiography.

METHODS AND RESULTS

Hemodynamically focused echocardiography as a rapidly available bedside method, enables the timely diagnosis and assessment of cardiac filling obstructions, volume status and volume response, right and left heart function, and the function of the heart valves.

CONCLUSION

Integrating all echocardiographic findings in a differentiated assessment of the patient's cardiovascular function enables a (patho)physiologically oriented and individualized hemodynamic treatment.

The use of lung ultrasound compared to chest X-ray to diagnose pneumothorax following the Nuss procedure for pectus excavatum repair in children

BACKGROUND

Pectus Excavatum is the most common deformation of the skeletal chest wall, and the Nuss procedure is used to correct this deformation. Residual pneumothorax is a frequent postoperative complication after thoracoscopy. Primary aim of this prospective observational study was to compare the level of agreement among readers using lung ultrasound and chest X-ray.

METHODS

This was an inter-reader single-center prospective observational agreement study for lung ultrasound and chest X-ray. Three lung ultrasound evaluations were performed at the end of surgery in the operating room by two Consultant Anesthesiologist (A1 and A2) and by a medical student (A3). Chest X-ray was interpreted by a consultant Radiologist (R1) and a pool of 11 radiologists (collectively named R2). Cohen's kappa was used to evaluate the level of agreement between the two imaging techniques.

RESULTS

Sixty-eight pediatric patients were included in the study. The overall agreement among (A = Anesthesiologist) A1, A2, A3, (R = Radiologist) R1, and R2 in assessing pneumothorax was fair (k = 0.32; 95% CI 0.21-0.40). The stratified analysis showed moderate inter-reader agreement among lung ultrasound readers A1, A2, and A3 (k 0.58; 95% CI 0.44-0.71), as opposed to the fair agreement found among chest X-ray readers R1 and R2 (k = 0.39; 95% CI 0.18-0.60).

CONCLUSIONS

Our results support the use of lung ultrasound to diagnose pneumothorax after Nuss procedure. We found that the inter-reader accuracy was better with ultrasound compared to X-ray at our institution.

Closing the loop on test results to reduce communication failures: a rapid review of evidence, practice and patient perspectives

Background

Communication failures involving test results contribute to issues of patient harm and sentinel events. This article aims to synthesise review evidence, practice insights and patient perspectives addressing problems encountered in the communication of diagnostic test results.

Methods

The rapid review identified ten systematic reviews and four narrative reviews. Five practitioner interviews identified insights into interventions and implementation, and a citizen panel with 15 participants explored the patient viewpoint.

Results

The rapid review provided support for the role of technology to ensure effective communication; behavioural interventions such as audit and feedback could be effective in changing clinician behaviour; and point-of-care tests (bedside testing) eliminate the communication breakdown problem altogether. The practice interviews highlighted transparency, and clarifying the lines of responsibility as central to improving test result communication. Enabling better information sharing, implementing adequate planning and utilising technology were also identified in the practice interviews as viable strategies to improve test result communication. The citizen panel highlighted technology as critical to improving communication of test results to both health professionals and patients. Patients also highlighted the importance of having different ways of accessing test results, which is particularly pertinent when ensuring suitability for vulnerable populations.

Conclusions

This paper draws together multiple perspectives on the problem of failures in diagnostic test results communication to inform appropriate interventions. Across the three studies, technology was identified as the most feasible option for closing the loop on test result communication. However, the importance of clear, consistent communication and more streamlined processes were also key elements that emerged.

Review registration

The protocol for the rapid review was registered with PROSPERO CRD42018093316.

Use of Handheld Point-of-Care Ultrasound in Emergency Airway Management

Emergency airway management (EAM) is associated with a high rate of complications, morbidity, and mortality. Handheld point-of-care ultrasound shows promise as an emerging technology to facilitate rapid screening for difficult laryngoscopy, identify the cricothyroid membrane for potential cricothyroidotomy, and assess for increased aspiration risk, as well as provide confirmation of proper endotracheal tube positioning. This review summarizes the available evidence for the use of point-of-care ultrasound in EAM, provides an algorithm to facilitate its incorporation into existing EAM practice to improve patient safety, and serves as a framework for future validation studies.

Preoperative Noninvasive Cardiac Testing in Older Adults with Hip Fracture: A Multi-Site Study

BACKGROUND/OBJECTIVES

For older adults with acute hip fracture, use of preoperative noninvasive cardiac testing may lead to delays in surgery, thereby contributing to worse outcomes. Our study objective was to evaluate the preoperative use of pharmacologic stress testing and transthoracic echocardiogram (TTE) in older adults hospitalized with hip fracture.

DESIGN

Retrospective chart review.

SETTING

Seven hospitals (three tertiary, four community) within a large health system.

PARTICIPANTS

Patients, aged 65 years and older, hospitalized with hip fracture (n = 1,079; mean age = 84.2 years; 75% female; 82% white; 36% married).

MEASUREMENTS

Data were extracted from electronic medical records. The study evaluated associations between patient factors as well as clinical outcomes (time to surgery [TTS], length of stay [LOS], and in-hospital mortality) and the use of preoperative noninvasive cardiac testing (pharmacologic stress tests or TTE). Descriptive statistics were calculated. Cox regression was performed for both TTS and LOS (evaluated as time-dependent variable); logistic regression was used for in-hospital mortality.

RESULTS

Although 34.3% (n = 370) had a preoperative TTE, .7% (n = 8) underwent a nuclear stress test and none had a dobutamine stress echocardiogram. Median TTS was 1.1 days (IQR [interquartile range] = .8-1.8 days), median LOS was 5.3 days (IQR = 4.2-7.2 days), and in-hospital mortality was 3% (n = 32). Patients admitted to the medical service had 3.5 times greater odds of undergoing a TTE compared with those on the orthopedic service (P < .001). Community hospitals had almost three times greater odds of preoperative TTE than tertiary centers (P < .001). In multivariable analysis, preoperative TTE was significantly associated with increased TTS (P < .001). No difference in mortality was found between patients with and without a preoperative TTE.

CONCLUSION

This study highlights the high rate of TTE in preoperative assessment of older adults with acute hip fracture. Given the association between TTE and longer TTS, further studies must clarify the role of preoperative TTE in this population. J Am Geriatr Soc 68:1690-1697, 2020.

Impact of point-of-care ultrasound on the hospital length of stay for internal medicine inpatients with cardiopulmonary diagnosis at admission: study protocol of a randomized controlled trial-the IMFCU-1 (Internal Medicine Focused Clinical Ultrasound) study

Background

Point-of-care ultrasound (POCUS) is emerging as a reliable and valid clinical tool that impacts diagnosis and clinical decision-making as well as timely intervention for optimal patient management. This makes its utility in patients admitted to internal medicine wards attractive. However, there is still an evidence gap in all the medical setting of how its use affects clinical variables such as length of stay, morbidity, and mortality.

Methods/design

A prospective randomized controlled trial assessing the effect of a surface POCUS of the heart, lungs, and femoral and popliteal veins performed by an internal medicine physician during the first 24 h of patient admission to the unit with a presumptive cardiopulmonary diagnosis. The University of Melbourne iHeartScan, iLungScan, and two-point venous compression protocols are followed to identify left and right ventricular function, significant valvular heart disease, pericardial and pleural effusion, consolidation, pulmonary edema, pneumothorax, and proximal deep venous thrombosis. Patient management is not commanded by the protocol and is at the discretion of the treating team. A total of 250 patients will be recruited at one tertiary hospital. Participants are randomized to receive POCUS or no POCUS. The primary outcome measured will be hospital length of stay. Secondary outcomes include the change in diagnosis and management, 30-day hospital readmission, and healthcare costs.

Discussion

This study will evaluate the clinical impact of multi-organ POCUS in internal medicine patients admitted with cardiopulmonary diagnosis on the hospital length of stay. Recruitment of participants commenced in September 2018 and is estimated to be completed by March 2020.

Trial registration

Australian and New Zealand Clinical Trial Registry, ACTRN12618001442291. Registered on 28 August 2018.

Transtracheal flow-regulated oxygen insufflation-a simple and safe method for prolonging safe apnoea time in difficult airway management: A report of two cases

In the absence of upper airway patency, supraglottic methods of oxygen delivery become ineffective. We present two semi-elective difficult airway cases where oxygenation via the supraglottic route was deemed impractical due to upper airway obstruction. In order to facilitate safe airway management, apnoeic oxygenation was delivered via a narrow bore transtracheal cannula using a flow-regulated oxygen insufflator. The potential for safely prolonging apnoea time with this technique in both elective and emergency settings is discussed.

Descriptive study of ultrasound images of the upper airway obtained after insertion of laryngeal mask

OBJECTIVE

To evaluate clinical usefulness of ultrasound images of the upper airway in order to check correct laryngeal mask placement.

MATERIAL AND METHODS

A prospective observational study was conducted on patients scheduled for abdominal surgery under general anaesthesia, in whom the patency of the upper airway was ensured using an Ambu^®AuraGain^TM laryngeal mask. An ultrasound scan was performed of the upper-airway in the cranio-caudal direction and with longitudinal scans in the anterior midline and parasagittal axis, in three moments: before, after inserting and after removing the mask. All recorded images were evaluated in a second time by a radiologist-expert in upper airway ultrasound. Subsequently, the ultrasound data were related to the clinical difficulty of the insertion and presence of air leaks.

RESULTS

Data was collected from 30 patients (20 females and 10 males) being operated on for abdominal hysterectomy (15), eventroplasty (6), uterine myomectomy (3), and umbilical (4) and inguinal herniorrhaphy (2). The blind insertion of the masks did not present difficulties in 24 (80%) patients. Air leakage was detected in 8 (26.7%) patients, which was moderate in 7 cases and severe in one of them. The ultrasound findings confirmed good mask placement in 22 (73.3%) patients. Anatomical airway changes after laryngeal mask extraction were only observed in 3 (12%) patients, all of them minor. There was a statistically significant association (P<.05) between difficulty in inserting the device and the level of air leakage.

CONCLUSIONS

Upper airway ultrasound is a useful diagnostic method to evaluate laryngeal mask placement. Laryngeal oedema was not observed after removal of the device.