Evaluation of the impact of artificial intelligence-assisted image interpretation on the diagnostic performance of clinicians in identifying pneumothoraces on plain chest X-ray: a multi-case multi-reader study.

BACKGROUND: Artificial intelligence (AI)-assisted image interpretation is a fast-developing area of clinical innovation. Most research to date has focused on the performance of AI-assisted algorithms in comparison with that of radiologists rather than evaluating the algorithms' impact on the clinicians who often undertake initial image interpretation in routine clinical practice. This study assessed the impact of AI-assisted image interpretation on the diagnostic performance of frontline acute care clinicians for the detection of pneumothoraces (PTX). METHODS: A multicentre blinded multi-case multi-reader study was conducted between October 2021 and January 2022. The online study recruited 18 clinician readers from six different clinical specialties, with differing levels of seniority, across four English hospitals. The study included 395 plain CXR images, 189 positive for PTX and 206 negative. The reference standard was the consensus opinion of two thoracic radiologists with a third acting as arbitrator. General Electric Healthcare Critical Care Suite (GEHC CCS) PTX algorithm was applied to the final dataset. Readers individually interpreted the dataset without AI assistance, recording the presence or absence of a PTX and a confidence rating. Following a 'washout' period, this process was repeated including the AI output. RESULTS: Analysis of the performance of the algorithm for detecting or ruling out a PTX revealed an overall AUROC of 0.939. Overall reader sensitivity increased by 11.4% (95% CI 4.8, 18.0, p=0.002) from 66.8% (95% CI 57.3, 76.2) unaided to 78.1% aided (95% CI 72.2, 84.0, p=0.002), specificity 93.9% (95% CI 90.9, 97.0) without AI to 95.8% (95% CI 93.7, 97.9, p=0.247). The junior reader subgroup showed the largest improvement at 21.7% (95% CI 10.9, 32.6), increasing from 56.0% (95% CI 37.7, 74.3) to 77.7% (95% CI 65.8, 89.7, p<0.01). CONCLUSION: The study indicates that AI-assisted image interpretation significantly enhances the diagnostic accuracy of clinicians in detecting PTX, particularly benefiting less experienced practitioners. While overall interpretation time remained unchanged, the use of AI improved diagnostic confidence and sensitivity, especially among junior clinicians. These findings underscore the potential of AI to support less skilled clinicians in acute care settings.

COVID-19-Related Pleural Diseases.

Coronavirus disease 2019 (COVID-19)-related pleural diseases are now well recognized. Since the beginning of the pandemic, increasing cases of pleural diseases including pneumothorax, pneumomediastinum, and pleural effusion with severe COVID-19 infection have attracted the attention of physicians and are not incidental or due to barotrauma. The complicated course of COVID-19 illness highlights the complex pathophysiological underpinnings of pleural complications. The management of patients with pneumothorax and pneumomediastinum is challenging as the majority require assisted ventilation; physicians therefore appear to have a low threshold to intervene. Conversely, pleural effusion cases, although sharing some similar patient characteristics with pneumothorax and pneumomediastinum, are in general managed more conservatively. The evidence suggests that patients with COVID-19-related pleural diseases, either due to air leak or effusion, have more severe disease with a worse prognosis. This implies that prompt recognition of these complications and targeted management are key to improve outcomes.

Cost-effectiveness of ambulatory care management of primary spontaneous pneumothorax: an open-label, randomised controlled trial.

BACKGROUND: Ambulatory management of primary spontaneous pneumothorax has been shown to reduce initial hospitalisation, but at the expense of increase adverse events. As a result, questions remain about the cost-effectiveness of this option. OBJECTIVES: A within-trial economic evaluation alongside a randomised controlled trial was performed to assess the cost-effectiveness of ambulatory care when compared with standard guideline-based management. METHODS: Patients were randomly assigned to treatment with either an ambulatory device or standard guideline-based management (aspiration, standard chest tube insertion or both). Follow-up was 12 months. Outcomes included healthcare resource use and costs, quality of life, quality-adjusted life-years (QALYs) and cost-effectiveness. RESULTS: 236 patients were recruited and randomly assigned to ambulatory care (n=117) and standard care (n=119). After multiple imputation for missing data, patients in the ambulatory care group had significantly lower National Health Service healthcare costs (-£788, 95% CI difference: -1527 to -50; p=0.037) than those in the standard care group. There were no differences in the number of QALYs gained (mean difference: -0.001, 95% CI difference: -0.032 to 0.030; p=0.95). When standard care was compared with ambulatory care, the incremental cost-effectiveness ratio was £799 066 per QALY gained, well above current thresholds of cost-effectiveness. As a result, the probability of ambulatory care being cost-effective was 0.93. CONCLUSION: Outpatient ambulatory management is highly likely to be a cost-effective option in the management of primary pneumothorax. TRIAL REGISTRATION NUMBER: ISRCTN79151659.

Pneumothorax management: current state of practice in the UK.

BACKGROUND AND OBJECTIVE: Spontaneous pneumothorax is a common pathology but optimal initial treatment regime is not well defined. Treatment options including conservative management, needle aspiration (NA) or insertion of a small-bore chest drain. Recent large randomised controlled trials may change the treatment paradigm: comparing conservative and ambulatory management to standard care, but current guidelines need to be updated. The aim of this study was to assess the current "state of play" in the management of pneumothorax in the UK. METHODS: Physicians and respiratory healthcare staff were invited to complete an online survey on the initial and subsequent management of pneumothorax. RESULTS: This study is the first survey of pneumothorax practice across the UK, which highlights variation in practice: 50% would manage a large primary pneumothorax with minimal symptoms conservatively, compared to only 3% if there were significant symptoms; 64% use suction if the pneumothorax had not resolved after > 2 days, 15% always clamp the chest drain prior to removal; whereas 30% never do. NICE guidance recommends the use of digital suction but this has not translated into widespread usage: only 23% use digital suction to check for resolution of air leak). CONCLUSION: Whilst there has always been allowance for individual clinician preference in guidelines, there needs to be consensus on the optimum management strategy. The challenge the new guidelines face is to design a simple and pragmatic approach, using this new evidence base.

Ambulatory management of primary spontaneous pneumothorax: an open-label, randomised controlled trial.

BACKGROUND: Primary spontaneous pneumothorax occurs in otherwise healthy young patients. Optimal management is not defined and often results in prolonged hospitalisation. Data on efficacy of ambulatory options are poor. We aimed to describe the duration of hospitalisation and safety of ambulatory management compared with standard care. METHODS: In this open-label, randomised controlled trial, adults (aged 16-55 years) with symptomatic primary spontaneous pneumothorax were recruited from 24 UK hospitals during a period of 3 years. Patients were randomly assigned (1:1) to treatment with either an ambulatory device or standard guideline-based management (aspiration, standard chest tube insertion, or both). The primary outcome was total length of hospital stay including re-admission up to 30 days after randomisation. Patients with available data were included in the primary analysis and all assigned patients were included in the safety analysis. The trial was prospectively registered with the International Standard Randomised Clinical Trials Number, ISRCTN79151659. FINDINGS: Of 776 patients screened between July, 2015, and March, 2019, 236 (30%) were randomly assigned to ambulatory care (n=117) and standard care (n=119). At day 30, the median hospitalisation was significantly shorter in the 114 patients with available data who received ambulatory treatment (0 days [IQR 0-3]) than in the 113 with available data who received standard care (4 days [IQR 0-8]; p<0·0001; median difference 2 days [95% CI 1-3]). 110 (47%) of 236 patients had adverse events, including 64 (55%) of 117 patients in the ambulatory care arm and 46 (39%) of 119 in the standard care arm. All 14 serious adverse events occurred in patients who received ambulatory care, eight (57%) of which were related to the intervention, including an enlarging pneumothorax, asymptomatic pulmonary oedema, and the device malfunctioning, leaking, or dislodging. INTERPRETATION: Ambulatory management of primary spontaneous pneumothorax significantly reduced the duration of hospitalisation including re-admissions in the first 30 days, but at the expense of increased adverse events. This data suggests that primary spontaneous pneumothorax can be managed for outpatients, using ambulatory devices in those who require intervention. FUNDING: UK National Institute for Health Research.

European Respiratory Society statement on thoracic ultrasound.

Thoracic ultrasound is increasingly considered to be an essential tool for the pulmonologist. It is used in diverse clinical scenarios, including as an adjunct to clinical decision making for diagnosis, a real-time guide to procedures and a predictor or measurement of treatment response. The aim of this European Respiratory Society task force was to produce a statement on thoracic ultrasound for pulmonologists using thoracic ultrasound within the field of respiratory medicine. The multidisciplinary panel performed a review of the literature, addressing major areas of thoracic ultrasound practice and application. The selected major areas include equipment and technique, assessment of the chest wall, parietal pleura, pleural effusion, pneumothorax, interstitial syndrome, lung consolidation, diaphragm assessment, intervention guidance, training and the patient perspective. Despite the growing evidence supporting the use of thoracic ultrasound, the published literature still contains a paucity of data in some important fields. Key research questions for each of the major areas were identified, which serve to facilitate future multicentre collaborations and research to further consolidate an evidence-based use of thoracic ultrasound, for the benefit of the many patients being exposed to clinicians using thoracic ultrasound.

Ambulatory management of secondary spontaneous pneumothorax: a randomised controlled trial.

Secondary spontaneous pneumothorax (SSP) is traditionally managed with an intercostal chest tube attached to an underwater seal. We investigated whether use of a one-way flutter valve shortened patients' length of stay (LoS).This open-label randomised controlled trial enrolled patients presenting with SSP and randomised to either a chest tube and underwater seal (standard care: SC) or ambulatory care (AC) with a flutter valve. The type of flutter valve used depended on whether at randomisation the patient already had a chest tube in place: in those without a chest tube a pleural vent (PV) was used; in those with a chest tube in situ, an Atrium Pneumostat (AP) valve was attached. The primary end-point was LoS.Between March 2017 and March 2020, 41 patients underwent randomisation: 20 to SC and 21 to AC (13=PV, 8=AP). There was no difference in LoS in the first 30 days following treatment intervention: AC (median=6 days, IQR 14.5) and SC (median=6 days, IQR 13.3). In patients treated with PV there was a high rate of early treatment failure (6/13; 46%), compared to patients receiving SC (3/20; 15%) (p=0.11) Patients treated with AP had no (0/8 0%) early treatment failures and a median LoS of 1.5 days (IQR 23.8).There was no difference in LoS between ambulatory and standard care. Pleural Vents had high rates of treatment failure and should not be used in SSP. Atrium Pneumostats are a safer alternative, with a trend towards lower LoS.

Patient-derived malignant pleural mesothelioma cell cultures: a tool to advance biomarker-driven treatments.

Malignant pleural mesothelioma (MPM) is an aggressive cancer, associated with poor prognosis. We assessed the feasibility of patient-derived cell cultures to serve as an ex vivo model of MPM. Patient-derived MPM cell cultures (n=16) exhibited stemness features and reflected intratumour and interpatient heterogeneity. A subset of the cells were subjected to high-throughput drug screening and coculture assays with cancer-specific cytotoxic T cells and showed diverse responses. Some of the biphasic MPM cells were capable of processing and presenting the neoantigen SSX-2 endogenously. In conclusion, patient-derived MPM cell cultures are a promising and faithful ex vivo model of MPM.

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.

Prospective validation of the RAPID clinical risk prediction score in adult patients with pleural infection: the PILOT study.

BACKGROUND: Over 30% of adult patients with pleural infection either die and/or require surgery. There is no robust means of predicting at baseline presentation which patients will suffer a poor clinical outcome. A validated risk prediction score would allow early identification of high-risk patients, potentially directing more aggressive treatment thereafter. OBJECTIVES: To prospectively assess a previously described risk score (the RAPID (Renal (urea), Age, fluid Purulence, Infection source, Dietary (albumin)) score) in adults with pleural infection. METHODS: Prospective observational cohort study that recruited patients undergoing treatment for pleural infection. RAPID score and risk category were calculated at baseline presentation. The primary outcome was mortality at 3 months; secondary outcomes were mortality at 12 months, length of hospital stay, need for thoracic surgery, failure of medical treatment and lung function at 3 months. RESULTS: Mortality data were available in 542 out of 546 patients recruited (99.3%). Overall mortality was 10% at 3 months (54 out of 542) and 19% at 12 months (102 out of 542). The RAPID risk category predicted mortality at 3 months. Low-risk mortality (RAPID score 0-2): five out of 222 (2.3%, 95% CI 0.9 to 5.7%); medium-risk mortality (RAPID score 3-4): 21 out of 228 (9.2%, 95% CI 6.0 to 13.7%); and high-risk mortality (RAPID score 5-7): 27 out of 92 (29.3%, 95% CI 21.0 to 39.2%). C-statistics for the scores at 3 months and 12 months were 0.78 (95% CI 0.71-0.83) and 0.77 (95% CI 0.72-0.82), respectively. CONCLUSIONS: The RAPID score stratifies adults with pleural infection according to increasing risk of mortality and should inform future research directed at improving outcomes in this patient population.

Predicting outcomes in primary spontaneous pneumothorax using air leak measurements.

The initial treatment regime for primary spontaneous pneumothorax (PSP) is generic and non-personalised, often involving a long hospital stay waiting for air leak to cease. This prospective study of 81 patients with PSP, who required drain insertion, captured daily digital air leak measurements and assessed failure of medical management against prespecified criteria. Patients with higher air leak at day 1 or 2 had significantly longer hospital stay. If air leak was ≥100 mL/min on day 1, the adjusted OR of treatment failure was 5.2 (95% CI 1.2 to 22.6, p=0.03), demonstrating that early digital air leak measurements could potentially predict future medical treatment failure. TRIAL REGISTRATION NUMBER: ISRCTN79151659.

Pneumothorax-Time for New Guidelines?

Pneumothorax is a common pathology, but optimal management strategies are not yet defined. There are significant differences in international guidelines and therefore variation in clinical practice.There is increasing interest in pneumothorax research, particularly primary spontaneous pneumothorax (PSP), with evidence of lung abnormalities in this group without clinically apparent lung disease and recently completed clinical trials aiming to optimize management. The most robust evidence base is that of the equivalence of needle aspiration and chest tube insertion for initial management of PSP; although, patients with secondary spontaneous pneumothorax may also benefit. A convincing case for surgical intervention or thoracoscopy and talc poudrage to prevent recurrence at first episode in PSP has yet to be made. Clinicians should be vigilant for PSP being the first manifestation of a systemic disease, and should have a low threshold for onward referral. Time to change guidelines? First, chest tube drainage and hospitalization without recurrence prevention should no longer be standard treatment, as this has no advantage over the less invasive manual aspiration, which moreover can be performed on an outpatient basis in an important number of patients. The results of recent trials in conservative and ambulatory management are eagerly awaited. Second, shared decision-making should become more important with the well-informed patient, who may want to avoid a 1 in 3 recurrence rate and therefore will have the possibility to choose treatment including recurrence prevention even after the first episode of PSP. Third, surgical research should urgently make clear if the current practice of resection of emphysema-like changes is routinely necessary, alongside pleurodesis. Future studies should utilize risk stratification by clinical and radiological parameters (e.g., high-resolution computed tomography scanning and digital air leak monitoring) to predict short- and long-term outcomes, and hence personalize management.

Trends in the Incidence and Recurrence of Inpatient-Treated Spontaneous Pneumothorax, 1968-2016.

Importance: Spontaneous pneumothorax is a common disease known to have an unusual epidemiological profile, but there are limited contemporary population-based data. Objective: To estimate the incidence of hospital admissions for spontaneous pneumothorax, its recurrence and trends over time using large, longstanding hospitalization data sets in England. Design, Setting, and Participants: A population-based epidemiological study was conducted using an English national data set and an English regional data set, each spanning 1968 to 2016, and including 170 929 hospital admission records of patients 15 years and older. Final date of the study period was December 31, 2016. Exposures: Calendar year (for incidence) and readmission to hospital for spontaneous pneumothorax (for recurrence). Main Outcomes and Measures: Primary outcomes were rates of hospital admissions for spontaneous pneumothorax and recurrence, defined as a subsequent hospital readmission with spontaneous pneumothorax. Record-linkage was used to identify multiple admissions per person and comorbidity. Risk factors for recurrence over 5 years of follow-up were assessed using cumulative time-to-failure analysis and Cox proportional hazards regression. Results: From 1968 to 2016, there were 170 929 hospital admissions for spontaneous pneumothorax (median age, 44 years [IQR, 26-88]; 73.0% male). In 2016, there were 14.1 spontaneous pneumothorax admissions per 100 000 population 15 years and older (95% CI, 13.7-14.4), a significant increase compared with earlier years, up from 9.1 (95% CI, 8.1-10.1) in 1968. The population-based rate per 100 000 population 15 years and older was higher for males (20.8 [95% CI, 20.2-21.4]) than for females (7.6 [95% CI, 7.2-7.9]). Of patients with spontaneous pneumothorax, 60.8% (95% CI, 59.5%-62.0%) had chronic lung disease. Record-linkage analysis demonstrated that the overall increase in admissions over time could be due in part to an increase in repeat admissions, but there were also significant increases in the annual rate of first-known spontaneous pneumothorax admissions in some population subgroups, for example in women 65 years and older (annual percentage change from 1968 to 2016, 4.08 [95% CI, 3.33-4.82], P < .001). The probability of recurrence within 5 years was similar by sex (25.5% [95% CI, 25.1%-25.9%] for males vs 26.0% [95% CI, 25.3%-26.7%] for females), but there was variation by age group and presence of chronic lung disease. For example, the probability of readmission within 5 years among males aged 15 to 34 years with chronic lung disease was 39.2% (95% CI, 37.7%-40.7%) compared with 19.6% (95% CI, 18.2%-21.1%) in men 65 years and older without chronic lung disease. Conclusions and Relevance: This study provides contemporary information regarding the trends in incidence and recurrence of inpatient-treated spontaneous pneumothorax.