Diagnostic accuracy, safety and utilisation of respiratory physician-delivered thoracic ultrasound

Thoracic ultrasound use in hospitalized and ambulatory adult patients: a quantitative picture

INTRODUCTION AND OBJECTIVES

Thoracic ultrasound (TUS) has been established as a powerful diagnostic and monitoring tool in the Intensive Care Unit (ICU). However, studies outside the critical care setting are scarce. The aim of this study was to investigate the value of TUS for hospitalized or ambulatory community patients.

MATERIALS AND METHODS

This was a retrospective study conducted from 2016 to 2020 in the TUS clinic at Heraklion University Hospital. TUS examination was performed using a standard ultrasound machine (EUB HITACHI 8500), and a high-frequency microconvex probe (5-8 MHz). Patients had been referred by their primary physician to address a range of different questions. The various respiratory system entities were characterised according to internationally established criteria.

RESULTS

762 TUS studies were performed on 526 patients due to underlying malignancy (n = 376), unexplained symptoms/signs (n = 53), pregnancy related issues (n = 42), evaluation of abnormal findings in X-ray (n = 165), recent surgery/trauma (n = 23), recent onset respiratory failure (n = 12), acute respiratory infection (n = 66) and underlying non-malignant disease (n = 25). Pleural effusion was the commonest pathologic entity (n = 610), followed by consolidation (n = 269), diaphragmatic dysfunction/paradox (n = 174) and interstitial syndrome (n = 53). Discrepancies between chest X-ray and ultrasonographic findings were demonstrated in 96 cases. The TUS findings guided invasive therapeutic management in 448 cases and non-invasive management in 43 cases, while follow-up monitoring was decided in 271 cases.

CONCLUSIONS

This study showed that TUS can identify the most common respiratory pathologic entities encountered in hospitalized and community ambulatory patients, and is especially useful in guiding the decision making process in a diverse group of patients.

From Bedside to the Bench—A Call for Novel Approaches to Prognostic Evaluation and Treatment of Empyema

Empyema, a severe complication of pneumonia, trauma, and surgery is characterized by fibrinopurulent effusions and loculations that can result in lung restriction and resistance to drainage. For decades, efforts have been focused on finding a universal treatment that could be applied to all patients with practice recommendations varying between intrapleural fibrinolytic therapy (IPFT) and surgical drainage. However, despite medical advances, the incidence of empyema has increased, suggesting a gap in our understanding of the pathophysiology of this disease and insufficient crosstalk between clinical practice and preclinical research, which slows the development of innovative, personalized therapies. The recent trend towards less invasive treatments in advanced stage empyema opens new opportunities for pharmacological interventions. Its remarkable efficacy in pediatric empyema makes IPFT the first line treatment. Unfortunately, treatment approaches used in pediatrics cannot be extrapolated to empyema in adults, where there is a high level of failure in IPFT when treating advanced stage disease. The risk of bleeding complications and lack of effective low dose IPFT for patients with contraindications to surgery (up to 30%) promote a debate regarding the choice of fibrinolysin, its dosage and schedule. These challenges, which together with a lack of point of care diagnostics to personalize treatment of empyema, contribute to high (up to 20%) mortality in empyema in adults and should be addressed preclinically using validated animal models. Modern preclinical studies are delivering innovative solutions for evaluation and treatment of empyema in clinical practice: low dose, targeted treatments, novel biomarkers to predict IPFT success or failure, novel delivery methods such as encapsulating fibrinolysin in echogenic liposomal carriers to increase the half-life of plasminogen activator. Translational research focused on understanding the pathophysiological mechanisms that control 1) the transition from acute to advanced-stage, chronic empyema, and 2) differences in outcomes of IPFT between pediatric and adult patients, will identify new molecular targets in empyema. We believe that seamless bidirectional communication between those working at the bedside and the bench would result in novel personalized approaches to improve pharmacological treatment outcomes, thus widening the window for use of IPFT in adult patients with advanced stage empyema.

Volume Balance in Chronic Kidney Disease: Evaluation Methodologies and Innovation Opportunities

BACKGROUND

Patients affected by chronic kidney disease are at a risk of cardiovascular morbidity and mortality. Body fluids unbalance is one of the main characteristics of this condition, as fluid overload is highly prevalent in patients affected by the cardiorenal syndrome.

SUMMARY

We describe the state of the art and new insights into body volume evaluation. The mechanisms behind fluid balance are often complex, mainly because of the interplay of multiple regulatory systems. Consequently, its management may be challenging in clinical practice and even more so out-of-hospital. Availability of novel technologies offer new opportunities to improve the quality of care and patients' outcome. Development and validation of new technologies could provide new tools to reduce costs for the healthcare system, promote personalized medicine, and boost home care. Due to the current COVID-19 pandemic, a proper monitoring of chronic patients suffering from fluid unbalances is extremely relevant. Key Message: We discuss the main mechanisms responsible for fluid overload in different clinical contexts, including hemodialysis, peritoneal dialysis, and heart failure, emphasizing the potential impact provided by the implementation of the new technologies.

Is Bigger Really Better? Comparison of Ultraportable Handheld Ultrasound with Standard Point-of-Care Ultrasound for Evaluating Safe Site Identification and Image Quality prior to Pleurocentesis

BACKGROUND

Pleural effusions remain a common medical problem which often requires diagnostic pleurocentesis to determine the underlying cause. Pleurocentesis is a frequently performed procedure worldwide with improved safety using ultrasound (US) technology.

OBJECTIVES

This prospective, single-center study evaluated the use of an ultraportable handheld (UPHH) US compared with standard point-of-care (SPOC) US in determining a safe site for pleurocentesis. In addition, US image quality and factors impacting on image quality were assessed using both UPHH and SPOC US.

METHODS

Paired US assessments were performed by thoracic physicians using UPHH and SPOC US on patients with unilateral pleural effusions to determine a safe site for pleurocentesis (defined as >2 cm of pleural fluid, >2 cm from a solid organ/diaphragm, and <7 cm chest wall depth). Distance measurements for key structures and image quality scores (using a 5-point Likert rating scale) were obtained at the time of US assessment. Factors affecting image quality were analyzed using univariate analysis.

RESULTS

In 52 of the 54 included patients (96.3%), UPHH US was able to identify a safe site for pleurocentesis. Distance measurements between UPHH and SPOC US were not statistically different (all <0.5 cm with values of p > 0.05), but image quality was reduced in UPHH compared with SPOC US by 1 point on a 5-point Likert rating scale (p < 0.002). Increasing body mass index was associated with a reduction in image quality in both UPHH and SPOC US (all p < 0.01).

CONCLUSIONS

Although image quality was lower in UPHH than SPOC US, a safe site was found in 96.3% of patients, which suggests that UPHH US may be a useful tool for diagnostic pleuro-centesis when SPOC US is not available (http://www.anzctr.org.au/, Australia New Zealand Clinical Trials Registry, No. ACTRN12618001592235).

Intercostal vessel screening prior to pleural interventions by the respiratory physician: a prospective study of real world practice

INTRODUCTION

The rising incidence of pleural disease is seeing an international growth of pleural services, with physicians performing an ever-increasing volume of pleural interventions. These are frequently conducted at sites without immediate access to thoracic surgery or interventional radiology and serious complications such as pleural bleeding are likely to be under-reported.

AIM

To assess whether intercostal vessel screening can be performed by respiratory physicians at the time of pleural intervention, as an additional step that could potentially enhance safe practice.

METHODS

This was a prospective, observational study of 596 ultrasound-guided pleural procedures conducted by respiratory physicians and trainees in a tertiary centre. Operators did not have additional formal radiology training. Intercostal vessel screening was performed using a low frequency probe and the colour Doppler feature.

RESULTS

The intercostal vessels were screened in 95% of procedures and the intercostal artery (ICA) was successfully identified in 53% of cases. Screening resulted in an overall site alteration rate of 16% in all procedures, which increased to 30% when the ICA was successfully identified. This resulted in procedure abandonment in 2% of cases due to absence of a suitable entry site. Intercostal vessel screening was shown to be of particular value in the context of image-guided pleural biopsy.

CONCLUSION

Intercostal vessel screening is a simple and potentially important additional step that can be performed by respiratory physicians at the time of pleural intervention without advanced ultrasound expertise. Whether the widespread use of this technique can improve safety requires further evaluation in a multi-centre setting with a robust prospective study.

Outcomes of an initiative to improve inpatient safety of small bore thoracostomy tube insertion

Background

Intercostal chest catheter (ICC) insertion is a common hospital procedure with attendant risks including life‐threatening complications such as pneumothorax and visceral damage.

Aim

To investigate the effect of a quality improvement (QI) initiative on complications associated with inpatient thoracostomy tube insertion.

Methods

Following an audit of ICC complications in inpatients over a 2‐year period we implemented a comprehensive QI programme. This involved formal training in and mandatory use of thoracic ultrasound, standardisation of the procedure and documentation, a dedicated procedure room with nurses trained in assisting ICC insertion and senior supervision for medical staff. An audit over 2 years post‐implementation of the QI protocol was compared with pre‐implementation results.

Results

A total of 103 cases were reviewed pre‐implementation and 105 cases were reviewed post‐implementation of the QI programme. All procedures following the QI initiative were image guided compared to 23.3% of cases pre‐implementation. The rate of developing a pneumothorax requiring intervention post‐implementation was less than pre‐implementation (1.9% vs 5.8% (P = 0.023). Post‐implementation, there were no instances of dry taps, viscera perforation, clinically significant bleeding or wrong side ICC insertion and documentation improved.

Conclusion

QI initiative applied to thoracostomy tube insertion in hospital inpatients can reduce complications and improve procedure documentation.

Application of Lung Ultrasound in Critical Care Setting: A Review

This article reviews the use of thoracic ultrasound in the intensive care unit (ICU). The focus of this article is to review the basic terminology and clinical applications of thoracic ultrasound. The diagnostic approach to a breathless patient, the blue protocol, is presented in a simplified flow chart. The diagnostic application of thoracic ultrasound in lung parenchymal and pleural diseases, role in bedside procedures, diaphragmatic assessment, and lung recruitment are described. Recent updates discussed in this review help support its increasingly indispensable role in the emergent and critical care setting.

Sonographic Indicators for Treatment Choice and Follow-Up in Patients with Pleural Effusion

Aim

The aim of this study was to evaluate the role of thoracic sonography in treatment of pleural effusions and to identify sonographic indicators for surgical intervention.

Materials and Methods

This study included 378 patients with pleural effusions. US characteristics of effusions as the echo structure and pleural thickening were analyzed. Regarding the US finding, the diagnostic or therapeutic procedure was performed.

Results

The study included 267 male and 111 female patients, an average of 56.7 years. Infection was the most frequent cause of effusion. Two hundred sixty-nine patients had loculated and 109 free pleural effusion. Most frequent echo structure of loculated effusion was complex septate, whereas free effusion was mostly anechoic. Successful obtaining of the pleural fluid without real-time guidance was in 88% and under real-time guidance in 99% patients (p < 0.012). There was no significant difference in success rate between free and loculated effusion and regarding the echo structure (p=0.710 and 0.126, respectively). Complete fluid removal after serial thoracentesis or drainage was achieved in 86% patients. Forty-five patients with significantly thicker pleural peel and impairment of the diaphragmatic function than remaining of the group (p < 0.001) underwent surgery. Open thoracotomy and decortication was more frequently performed in patients with completely fixed diaphragm and complex, dominantly septated effusions. There is no significant difference in US parameters comparing to patients underwent VATS, but the number of VATS is too small for valid conclusion.

Conclusion

Thoracic sonography is a very useful tool in the evaluation of clinical course and treatment options in patients with pleural effusions of a different origin.

The Benefit of Ultrasound in Deciding Between Tube Thoracostomy and Observative Management in Hemothorax Resulting from Blunt Chest Trauma

BACKGROUND

Hemothorax is most commonly resulted from a closed chest trauma, while a tube thoracostomy (TT) is usually the first procedure attempted to treat it. However, TT may lead to unexpected results and complications in some cases. The advantage of thoracic ultrasound (TUS) over a physical examination combined with chest radiograph (CXR) for diagnosing hemothorax¹ has been proposed previously. However, its benefits in terms of avoiding non-therapeutic TT have not yet been confirmed. Therefore, this study is aimed to evaluate the severity of hemothorax in blunt chest trauma patients by using TUS in order to avoid non-therapeutic TT in stable cases.

METHODS

The data from 46,036 consecutive patient visits to our trauma center over a four-year period were collected, and those with blunt chest trauma were identified. Patients who met any of the following criteria were excluded: transferred from another facility, with an abbreviated injury scale (AIS) score ≥ 2 for any region except the chest region, with a documented finding of tension pneumothorax or pneumothorax >10%, younger than 16 years old and with indications requiring any non-thoracic major operation. The decision to perform TT for those patients in the non-TUS group was made on the basis of CXR findings and clinical symptoms. The continuous data were analyzed by using the two-tailed Student's t test, and the discrete data were analyzed by Chi-square test.

RESULTS

A total of 84 patients met the criteria for inclusion in the final analysis, with TT having been performed on 42 (50%) of those patients. The mean volume of the drainage amount was 860 ml after TT. The TT drainage was less than 500 ml in 12 patients in the non-TUS group (40%), while none was less than 500 ml in the TUS group (p = 0.036, Fisher's exact test). In terms of the positive rate of subsequent effective TT, the sensitivity of TUS was 90% and the specificity was 100%. There were 3 patients with delayed hemothorax: 2 of the 58 (3.6%) in the non-TUS group and 1 of 26 (4.5%) in the TUS group (p > 0.05, Fisher's exact test). The hospital length of stay in the non-TUS group with non-therapeutic TT was significantly longer than in the TUS group without TT (8.2 vs. 5.4 days, p = 0.018). There were no other major complications or deaths in either group during the 90-day follow-up period.

CONCLUSION

In the case of blunt trauma, TUS can rapidly and accurately evaluate hemothorax to avoid TT in patients who may not benefit much from it. As a result, the rate of non-therapeutic TT can be decreased, and the influence on shortening hospital length of stay may be further evaluated with prospective controlled study.

Providing safe and effective pleural medicine services in the UK: an aspirational statement from UK pleural physicians

Physicians face considerable challenges in ensuring safe and effective care for patients admitted to hospital with pleural disease. While subspecialty development has driven up standards of care, this has been tempered by the resulting loss of procedural experience in general medical teams tasked with managing acute pleural disease. This review aims to define a framework though which a minimum standard of care might be implemented. This review has been written by pleural clinicians from across the UK representing all types of secondary care hospital. Its content has been formed on the basis of literature review, national guidelines, National Health Service England policy and consensus opinion following a round table discussion. Recommendations have been provided in the broad themes of procedural training, out-of-hours management and pleural service specification. Procedural competences have been defined into descriptive categories: emergency, basic, intermediate and advanced. Provision of emergency level operators at all times in all trusts is the cornerstone of out-of-hours recommendations, alongside readily available escalation pathways. A proposal for minimum standards to ensure the safe delivery of pleural medicine have been described with the aim of driving local conversations and providing a framework for service development, review and risk assessment.

Point-of-Care Lung Sonography: An Audit of 1150 Examinations

OBJECTIVES

Point-of-care lung sonography has theoretical usefulness in numerous diseases; however clinical indications and the impact of this technique have not been fully investigated. We aimed to describe the current use of point-of-care lung sonography.

METHODS

A 2-year prospective observational study was performed by pulmonologists in an Italian university hospital. Techniques, indications, consequences of lung sonography, and barriers to the examination were analyzed.

RESULTS

A total of 1150 lung sonographic examinations were performed on 951 patients. The most common indications were diagnosis and follow-up of pleural effusion in 361 cases (31%), evaluation of lung consolidation (322 [28%]), acute heart failure (195 [17%]), guide to pleural procedures (117 [10%]), pneumothorax (54 [5%]) and acute exacerbations of chronic obstructive pulmonary disease (30 [3%]). The mean duration of the examination ± SD was 6 ± 4 minutes. The transducers most frequently used were convex (746 [65%]) and linear (161 [14%]), whereas in 205 examinations (18%), both transducers were used. According to the judgment of the caring clinician, 51% of the examinations were clinically relevant.

CONCLUSIONS

Point-of-care lung sonography performed by pulmonologists is quick and feasible and could be widely used for different clinical indications with a potentially high clinical impact. The widespread use of this technique may have a relevant clinical impact in several indications.

A prospective cohort study of thoracic ultrasound in acute respiratory failure: the C3PO protocol

OBJECTIVES

This study was performed to assess the clinical utility of a standardised thoracic ultrasound examination when added to standard care in patients with acute respiratory failure admitted to an intermediate care unit. This study aimed to assess the impact on clinical diagnosis, clinician confidence and management. Ultrasound has been shown to have utility in patients admitted to intensive care and emergency; however, utility in a ward setting is unknown.

DESIGN

Prospective cohort study.

SETTING

Tertiary hospital in Melbourne, Australia.

PARTICIPANTS

50 patients with acute respiratory failure requiring admission to an intermediate care unit.

MAIN OUTCOME MEASURES

(1) Change in clinical diagnosis or additional clinical diagnosis following thoracic ultrasound. (2) Change in diagnostic confidence following thoracic ultrasound. (3) Change to management following thoracic ultrasound.

RESULTS

In 34% of patients, ultrasound detected unexpected findings that changed or added to the clinical diagnosis. Diagnostic confidence was increased in 44%, and the treating clinician altered the management plan in 30% as a result of the ultrasound. Ultrasound was particularly useful in clarifying the diagnosis in patients with multiple initial diagnoses, reducing to a single diagnosis in 69%.

CONCLUSIONS

Thoracic ultrasound has clinical utility in non-intubated adults with acute respiratory failure managed outside intensive care settings. It changed aetiological diagnosis, increases diagnostic confidence and altered clinical management in one out of three patients scanned. Our results suggest extended utility of thoracic ultrasound in acute respiratory failure to a broader context outside the intensive care unit population.

The efficacy of bedside chest ultrasound: from accuracy to outcomes

For many respiratory physicians, point-of-care chest ultrasound is now an integral part of clinical practice. The diagnostic accuracy of ultrasound to detect abnormalities of the pleura, the lung parenchyma and the thoracic musculoskeletal system is well described. However, the efficacy of a test extends beyond just diagnostic accuracy. The true value of a test depends on the degree to which diagnostic accuracy efficacy influences decision-making efficacy, and the subsequent extent to which this impacts health outcome efficacy. We therefore reviewed the demonstrable levels of test efficacy for bedside ultrasound of the pleura, lung parenchyma and thoracic musculoskeletal system.For bedside ultrasound of the pleura, there is evidence supporting diagnostic accuracy efficacy, decision-making efficacy and health outcome efficacy, predominantly in guiding pleural interventions. For the lung parenchyma, chest ultrasound has an impact on diagnostic accuracy and decision-making for patients presenting with acute respiratory failure or breathlessness, but there are no data as yet on actual health outcomes. For ultrasound of the thoracic musculoskeletal system, there is robust evidence only for diagnostic accuracy efficacy.We therefore outline avenues to further validate bedside chest ultrasound beyond diagnostic accuracy, with an emphasis on confirming enhanced health outcomes.

Ultrasound in the management of pleural disease

INTRODUCTION

Pleural disease encompasses a large range of conditions, is a common presentation to the acute medical take and often requires comprehensive investigation and treatment. Ultrasound is well recognised as a useful investigative tool in pleural disease especially in the field of pleural effusion, pleural thickening and interventional procedures. Thoracic ultrasound (TUS) has gained widespread use by physicians as evidence has shown a reduced rate of complications when performing pleural procedures with ultrasound guidance. Areas covered: This article will review studies assessing the role of TUS in the management of pleural disease and examine ongoing research into how TUS could advance our knowledge and understanding over the next decade. Expert commentary: Physician lead thoracic ultrasound has become commonplace over the last decade, and now represents a minimum standard of safety in conducting the majority of 'bedside' pleural procedures. The current evidence points to important diagnostic and procedural roles of the use of bedside thoracic ultrasound. In the future, research developments are likely to lead to the use of thoracic ultrasound in prognostication, targeted treatment and understanding pathogenesis in pleural disease.

Thoracic Ultrasound: What Non-radiologists Need to Know

Purpose of review

The aim of this review is to provide the theoretical and practical knowledge essential for non-radiologists to develop the skills necessary to apply thoracic ultrasound as an extension of clinical assessment and intervention.

Recent findings

Issues relating to training and competence are discussed and a library of thoracic ultrasound videos is provided to illustrate artefacts, pleural, parenchymal and pneumothorax pathology as well as important pitfalls to consider. Novel and future diagnostic applications of thoracic ultrasound in the setting of acute cardiorespiratory pathology including consolidation, acute interstitial syndromes and pulmonary embolism are explored.

Summary

Thoracic ultrasound requires an understanding of imaging artefact specific to lung and pleura and a working knowledge of machine knobology for image optimisation and interpretation. Ultrasound is a valuable tool for the practicing chest clinician providing diagnostic information for the assessment of pleural and parenchymal disease and increased safety and cost effectiveness of thoracic interventions.

Electronic supplementary material

The online version of this article (doi:10.1007/s13665-017-0164-1) contains supplementary material, which is available to authorized users.

Accuracy and safety of ward based pleural ultrasound in the Australian healthcare system

BACKGROUND AND OBJECTIVE

Ultrasound has been shown to improve the accuracy and safety of pleural procedures. Studies to date have been performed in large, specialized units, where pleural procedures are performed by a small number of highly specialized physicians. There are no studies examining the safety and accuracy of ultrasound in the Australian healthcare system where procedures are performed by junior doctors with a high staff turnover.

METHODS

We performed a retrospective review of the ultrasound database in the Respiratory Department at the Royal Melbourne Hospital to determine accuracy and complications associated pleural procedures.

RESULTS

A total of 357 ultrasounds were performed between October 2010 and June 2013. Accuracy of pleural procedures was 350 of 356 (98.3%). Aspiration of pleural fluid was successful in 121 of 126 (96%) of patients. Two (0.9%) patients required chest tube insertion for management of pneumothorax. There were no recorded pleural infections, haemorrhage or viscera puncture.

CONCLUSION

Ward-based ultrasound for pleural procedures is safe and accurate when performed by appropriately trained and supported junior medical officers. Our findings support this model of pleural service care in the Australian healthcare system.

Pleural infection: past, present, and future directions

Pleural space infections are increasing in incidence and continue to have high associated morbidity, mortality, and need for invasive treatments such as thoracic surgery. The mechanisms of progression from a non-infected, pneumonia-related effusion to a confirmed pleural infection have been well described in the scientific literature, but the route by which pathogenic organisms access the pleural space is poorly understood. Data suggests that not all pleural infections can be related to lung parenchymal infection. Studies examining the microbiological profile of pleural infection inform antibiotic choice and can help to delineate the source and pathogenesis of infection. The development of radiological methods and use of clinical indices to predict which patients with pleural infection will have a poor outcome, as well as inform patient selection for more invasive treatments, is particularly important. Randomised clinical trial and case series data have shown that the combination of an intrapleural tissue plasminogen activator and deoxyribonuclease therapy can potentially improve outcomes, but the use of this treatment as compared with surgical options has not been precisely defined, particularly in terms of when and in which patients it should be used.

Creating thoracic phantoms for diagnostic and procedural ultrasound training

The use of pleural and lung ultrasound is being performed increasingly by respiratory and critical care clinicians around the world. This article describes how to create cheap and reliable lung and pleural phantoms for teaching. The phantoms described replicate the appearance of normal ventilating lung, pneumothorax (including the contact or lung point), pulmonary oedema, pleural effusion and empyema. The pleural effusion phantom can be used to teach procedural ultrasound (pleurocentesis).

Pleural procedural complications: prevention and management

Pleural disease is common with a rising case frequency. Many of these patients will be symptomatic and require diagnostic and/or therapeutic procedures. Patients with pleural disease present to a number of different medical specialties, and an equally broad range of clinicians are therefore required to have practical knowledge of these procedures. There is often underestimation of the morbidity and mortality associated with pleural interventions, even those regarded as being relatively straightforward, with potentially significant implications for processes relating to patient safety and informed consent. The advent of thoracic ultrasound (TUS) has had a major influence on patient safety and the number of physicians with the necessary skill set to perform pleural procedures. As the variety and complexity of pleural interventions increases, there is increasing recognition that early specialist input can reduce the risk of complications and number of procedures a patient requires. This review looks at the means by which complications of pleural procedures arise, along with how they can be managed or ideally prevented.

Can ultrasound guidance reduce the risk of pneumothorax following thoracentesis?

OBJECTIVE:

Thoracentesis is one of the bedside procedures most commonly associated with iatrogenic complications, particularly pneumothorax. Various risk factors for complications associated with thoracentesis have recently been identified, including an inexperienced operator; an inadequate or inexperienced support team; the lack of a standardized protocol; and the lack of ultrasound guidance. We sought to determine whether ultrasound-guided thoracentesis can reduce the risk of pneumothorax and improve outcomes (fewer procedures without fluid removal and greater volumes of fluid removed during the procedures). In our comparison of thoracentesis with and without ultrasound guidance, all procedures were performed by a team of expert pulmonologists, using the same standardized protocol in both conditions.

METHODS:

A total of 160 participants were randomly allocated to undergo thoracentesis with or without ultrasound guidance (n = 80 per group). The primary outcome was pneumothorax following thoracentesis. Secondary outcomes included the number of procedures without fluid removal and the volume of fluid drained during the procedure.

RESULTS:

Pneumothorax occurred in 1 of the 80 patients who underwent ultrasound-guided thoracentesis and in 10 of the 80 patients who underwent thoracentesis without ultrasound guidance, the difference being statistically significant (p = 0.009). Fluid was removed in 79 of the 80 procedures performed with ultrasound guidance and in 72 of the 80 procedures performed without it. The mean volume of fluid drained was larger during the former than during the latter (960 ± 500 mL vs. 770 ± 480 mL), the difference being statistically significant (p = 0.03).

CONCLUSIONS:

Ultrasound guidance increases the yield of thoracentesis and reduces the risk of post-procedure pneumothorax. (Chinese Clinical Trial Registry identifier: ChiCTR-TRC-12002174 [http://www.chictr.org/en/])

Direct ultrasound localisation for pleural aspiration: translating evidence into action

BACKGROUND

There is strong evidence that direct ultrasound localisation for pleural aspiration reduces complications, but this practice is not universal in Australia and New Zealand.

AIMS

To describe the current utilisation and logistical barriers to the use of direct ultrasound localisation for pleural aspiration by respiratory physicians from Australia and New Zealand, and to determine the cost benefits of procuring equipment and training resources in chest ultrasound.

METHODS

We surveyed all adult respiratory physician members of the Thoracic Society of Australia and New Zealand regarding their use of direct ultrasound localisation for pleural aspiration. We performed a cost-benefit analysis for acquiring bedside ultrasound equipment and estimated the capacity of available ultrasound training.

RESULTS

One hundred and forty-six of 275 respiratory physicians responded (53% response). One-third (33.6%) of respondents do not undertake direct ultrasound localisation. Lack of training/expertise (44.6%) and lack of access to ultrasound equipment (41%) were the most frequently reported barriers to performing direct ultrasound localisation. An average delay of 2 or more days to obtain an ultrasound performed in radiology was reported in 42.7% of respondents. Decision-tree analysis demonstrated that clinician-performed direct ultrasound localisation for pleural aspiration is cost-beneficial, with recovery of initial capital expenditure within 6 months. Ultrasound training infrastructure is already available to up-skill all respiratory physicians within 2 years and is cost-neutral.

CONCLUSION

Many respiratory physicians have not adopted direct ultrasound localisation for pleural aspiration because they lack equipment and expertise. However, purchase of ultrasound equipment is cost-beneficial, and there is already sufficient capacity to deliver accredited ultrasound training through existing services.

Physician-performed ultrasound can accurately screen for a vulnerable intercostal artery prior to chest drainage procedures

BACKGROUND AND OBJECTIVE

Laceration of the intercostal artery during pleural procedures is a rare but serious complication. This study evaluates the utility of thoracic ultrasound (US) to screen for a vulnerable vessel compared with the gold standard computed tomography (CT).

METHODS

Before undergoing contrast-enhanced CT chest, thoracic US was performed on 50 patients with a high-end and portable machine, and an attempt made to visualize the vessel at three positions across the back to the axilla. These positions were labelled with radio-opaque fiducial markers. On both US and CT images, the location of the vessel at each position, relative to the overlying rib, was calculated and compared.

RESULTS

The vessel was unshielded by a rib according to CT in 114 of the 133 positions. The sensitivity, specificity and negative predictive value of portable US to image the vessel, when it was within the intercostal space on CT, was 0.86, 0.30 and 0.27 respectively. The performance of a high-end machine was not significantly different. The median time required for a pulmonologist to locate the vessel was 42 s and 18 s for the portable and high-end US respectively.

CONCLUSIONS

US can be used to screen for a vulnerable vessel prior to pleural procedures, in a time amenable to use in clinical practice. Further, it is achievable by a pulmonologist using a portable US machine. If thoracentesis or chest tube insertion is being performed on a patient at increased risk of bleeding, screening for a vulnerable vessel with US prior to beginning the procedure is recommended.

A new instrument to assess physician skill at thoracic ultrasound, including pleural effusion markup

BACKGROUND

To reduce complications and increase success, thoracic ultrasound is recommended to guide all chest drainage procedures. Despite this, no tools currently exist to assess proceduralist training or competence. This study aims to validate an instrument to assess physician skill at performing thoracic ultrasound, including effusion markup, and examine its validity.

METHODS

We developed an 11-domain, 100-point assessment sheet in line with British Thoracic Society guidelines: the Ultrasound-Guided Thoracentesis Skills and Tasks Assessment Test (UGSTAT). The test was used to assess 22 participants (eight novices, seven intermediates, seven advanced) on two occasions while performing thoracic ultrasound on a pleural effusion phantom. Each test was scored by two blinded expert examiners. Validity was examined by assessing the ability of the test to stratify participants according to expected skill level (analysis of variance) and demonstrating test-retest and intertester reproducibility by comparison of repeated scores (mean difference [95% CI] and paired t test) and the intraclass correlation coefficient.

RESULTS

Mean scores for the novice, intermediate, and advanced groups were 49.3, 73.0, and 91.5 respectively, which were all significantly different (P &lt; .0001). There were no significant differences between repeated scores.

CONCLUSIONS

Procedural training on mannequins prior to unsupervised performance on patients is rapidly becoming the standard in medical education. This study has validated the UGSTAT, which can now be used to determine the adequacy of thoracic ultrasound training prior to clinical practice. It is likely that its role could be extended to live patients, providing a way to document ongoing procedural competence.

Pulmonary ultrasound examination for edema, effusion, and thromboembolism

Bedside, or point-of-care, ultrasound (US) has increasingly been used in various clinical settings to provide clinicians with rapid clinical information without the use of ionizing radiation. Lung US has been demonstrated as a valuable tool in the diagnosis and evaluation of pulmonary edema, pleural effusions, and pulmonary thromboembolism. Lung US enables the clinician to more quickly identify and initiate treatment for these potentially life-threatening conditions without the need for patient transportation to the radiology suite. Additionally, lung US can repeatedly be implemented to assess clinical changes without concern for repeated radiation exposure and is cost-effective given its ability to decrease the need for additional radiological and laboratory testing to confirm a suspected diagnosis. This review focuses on the application of lung US in the evaluation and management of pulmonary edema, pleural effusions, and pulmonary thromboembolism.

Current and future options for the diagnosis of malignant pleural effusion

INTRODUCTION

Malignant pleural effusion (MPE) is a frequent problem faced by clinicians, but tumor pleural involvement can be seen without effusion.

AREAS COVERED

Imaging, pleural fluid analysis, biomarkers for MPE, needle pleural biopsy and thoracoscopy. To prepare this review, we performed a search using keywords: 'diagnosis' + 'malignant' + 'pleural' + 'effusion' (all fields) in PubMed, and found 4106 articles overall (until 16 January 2013, 881 in the last 5 years).

EXPERT OPINION

Ultrasound techniques will stay as valuable tools for pleural effusions. Biomarkers in pleural fluid do not currently provide an acceptable yield for MPE. In subjects with past history of asbestos exposure, some serum or plasma markers (soluble mesothelin, fibulin) might help in selecting cases for close follow-up, to detect mesothelioma early. Needle pleural biopsy is justified only if used with image-techniques (ultrasound or CT) guidance, and thoracoscopy is better for both diagnosis and immediate palliative treatment (pleurodesis). Animal models of MPE and 'spheroids' are promising for research involving both pathophysiology and therapy. Considering the possibility of direct pleural delivery of nanotechnology-developed compounds-fit to both diagnosis and therapy purposes ('theranostics')-MPE and mesothelioma in particular are likely to benefit sooner than later from this exciting perspective.

Lung ultrasound in the management of acute decompensated heart failure

Once thought impracticable, lung ultrasound is now used in patients with a variety of pulmonary processes. This review seeks to describe the utility of lung ultrasound in the management of patients with acute decompensated heart failure (ADHF). A literature search was carried out on PubMed/Medline using search terms related to the topic. Over three thousand results were narrowed down via title and/or abstract review. Related articles were downloaded for full review. Case reports, letters, reviews and editorials were excluded. Lung ultrasonographic multiple B-lines are a good indicator of alveolar interstitial syndrome but are not specific for ADHF. The absence of multiple B-lines can be used to rule out ADHF as a causative etiology. In clinical scenarios where the assessment of acute dyspnea boils down to single or dichotomous pathologies, lung ultrasound can help rule in ADHF. For patients being treated for ADHF, lung ultrasound can also be used to monitor response to therapy. Lung ultrasound is an important adjunct in the management of patients with acute dyspnea or ADHF.

Revisiting tuberculous pleurisy: pleural fluid characteristics and diagnostic yield of mycobacterial culture in an endemic area

BACKGROUND

Tuberculous pleurisy is traditionally indicated by extreme lymphocytosis in pleural fluid and low yield of effusion culture. However, there is considerable inconsistency among previous study results. In addition, these data should be updated due to early effusion studies and advances in culture methods.

METHODS

From January 2004 to June 2009, patients with tuberculous pleurisy were retrospectively identified from the mycobacteriology laboratories and the pathology and tuberculosis registration databases of two hospitals in Taiwan where tuberculosis is endemic. Pleural fluid characteristics and yields of mycobacterial cultures using liquid media were evaluated.

RESULTS

A total of 382 patients with tuberculous pleurisy were identified. The median lymphocyte percentage of total cells in pleural fluids was 84% (IQR 64-95%) and 17% of cases had a lymphocyte percentage of <50%. The lymphocyte percentage was negatively associated with the probability of a positive effusion culture (OR 0.97; 95% CI 0.96 to 0.99). The diagnostic yields were 63% for effusion culture, 48% for sputum culture, 79% for the combination of effusion and sputum cultures, and 74% for histological examination of pleural biopsy specimens.

CONCLUSION

The degree of lymphocyte predominance in tuberculous pleurisy was lower than was previously thought. The lymphocyte percentage in pleural fluid was negatively associated with the probability of a positive effusion culture. With the implementation of a liquid culture method, the sensitivity of effusion culture was much higher than has been previously reported, and the combination of effusion and sputum cultures provided a good diagnostic yield.

Thoracic ultrasound demonstrates variable location of the intercostal artery

BACKGROUND

Ultrasound (US) guidance is advocated to reduce complications from thoracocentesis or intercostal catheter (ICC) insertion. Although imaging of the intercostal artery (ICA) with Doppler US has been reported, current thoracic guidelines do not advocate this, and bleeding from a lacerated ICA continues to be a rare but serious complication of thoracocentesis or ICC insertion.

OBJECTIVES

It was the aim of this study to describe a method to visualise the ICA at routine US-guided thoracocentesis and map its course across the posterior chest wall.

METHOD

The ICA was imaged in 22 patients undergoing US-guided thoracocentesis, at 4 positions across the back to the axilla. Its location, relative to the overlying rib, was calculated as the fraction of the intercostal space (ICS) below the inferior border of that rib.

RESULTS

An ICA was identified in 74 of 88 positions examined. The ICA migrated from a central 'vulnerable' location within the ICS near the spine (0.28, range 0.21-0.38; p < 0.001) towards the overlying rib (0.08, range 0.05-0.11; p < 0.001) in the axilla.

CONCLUSIONS

The ICA can be visualised with US and is more exposed centrally within the ICS in more posterior positions; however, there is a marked variation between individuals, such that the ICA may lie exposed in the ICS even as far lateral as the axilla. Future studies need to identify which patients are at risk for a 'low-lying' ICA to further define the role of US imaging of the ICA during thoracocentesis or ICC insertion.