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1.  Elimination of daily routine chest radiographs in a mixed medical–surgical intensive care unit 
Intensive Care Medicine  2007;33(4):639-644.
Objective
To determine the impact of elimination of daily routine chest radiographs (CXRs) in a mixed medical–surgical intensive care unit (ICU) on utility of on demand CXRs, length of stay (LOS) in ICU, readmission rate, and mortality rate.
Design and setting
Prospective, nonrandomized, controlled study in a 28-bed ICU. Analysis included data of all admitted ICU patients during 5 months before and after elimination of daily routine CXRs.
Results
Before elimination, 2457 daily routine CXRs and 1437 on demand CXRs were obtained from 754 patients. After elimination, 1267 CXRs were obtained from 622 patients. The ratio of CXRs/patient day decreased from 1.1 ± 0.3 to 0.6 ± 0.4 (p < 0.05). Elimination did not result in a change in utility and timing of on demand CXRs. The absolute diagnostic and therapeutic value of on demand CXRs increased with elimination of daily routine CXRs: before intervention, 147 unexpected predefined abnormalities were found (10.2% of all on demand CXRs in 15.9% of all patients), of which 57 (3.9%) in 6.4% of all patients led to a change in therapy. After intervention, 156 unexpected predefined abnormalities were found (11.6%; p < 0.05), of which 61 (4.8%) in 9.5% of all patients (p < 0.05) led to a change in therapy. The LOS in ICU, readmission rate and ICU, and hospital mortality rate were not influenced by the change in strategy.
Conclusions
Elimination of daily routine CXRs reduced the number of CXRs in a mixed medical–surgical ICU, while not affecting readmission rate and ICU and hospital mortality rates.
Electronic supplementary material
The online version of this article (doi:10.1007/s00134-007-0542-1) contains supplementary material, which is available to authorized users
doi:10.1007/s00134-007-0542-1
PMCID: PMC1915596  PMID: 17333118
Daily routine; On demand; Chest radiograph; ICU; Critical care
2.  Are daily routine chest radiographs necessary after pulmonary surgery in adult patients? 
A best evidence topic was constructed according to a structured protocol. The question addressed was whether daily routine (DR) chest radiographs (CXRs) are necessary after pulmonary surgery in adult patients. Of the 66 papers found using a report search, seven presented the best evidence to answer the clinical question. Four of these seven studies specifically addressed post-cardiothoracic adult patients. Three of these seven studies addressed intensive care unit (ICU) patients and included post-cardiothoracic adult patients in well-designed studies. Six of these seven studies compared the DR CXRs strategy to the clinically indicated, on-demand (OD) CXRs strategy. Another study analysed the clinical impact of ceasing to perform the DR, postoperative, post-chest tubes removal CXRs. The authors, journal, date and country of publication, study type, group studied, relevant outcomes and results of these papers are given. We conclude that, on the whole, the seven studies are unanimously in favour of forgoing DR CXRs after lung resection and advocate OD CXRs. One study suggested that hypoxic patients could benefit from a DR CXRs strategy, while other studies failed to identify any subgroup for whom performing DR CXRs was beneficial. Indeed, DR CXRs, commonly taken after thoracic surgery, have poor diagnostic and therapeutic value. Eliminating them for adult patients having undergone thoracic surgery significantly decreases the number of CXRs per patient without increasing mortality rates, length of hospital stays (LOSs), readmission rates and adverse events. Hence, current evidence shows that DR CXRs could be forgone after lung resection because OD CXRs, recommended by clinical monitoring, have a better impact on management and have not been proved to negatively affect patient outcomes. Moreover, an OD CXRs strategy lowers the cost of care. Nevertheless, an OD CXRs strategy requires close clinical monitoring by experienced surgeons and dedicated intensivists. However, given the published studies' low level of evidence, prospective and randomized trials, specifically after thoracic surgery, are necessary in order to confirm these results.
doi:10.1093/icvts/ivt352
PMCID: PMC3829488  PMID: 23956264
Thoracic surgery; Chest radiography; Outcomes; Cost of care
3.  The clinical value of daily routine chest radiographs in a mixed medical–surgical intensive care unit is low 
Critical Care  2005;10(1):R11.
Introduction
The clinical value of daily routine chest radiographs (CXRs) in critically ill patients is unknown. We conducted this study to evaluate how frequently unexpected predefined major abnormalities are identified with daily routine CXRs, and how often these findings lead to a change in care for intensive care unit (ICU) patients.
Method
This was a prospective observational study conducted in a 28-bed, mixed medical–surgical ICU of a university hospital.
Results
Over a 5-month period, 2,457 daily routine CXRs were done in 754 consecutive ICU patients. The majority of these CXRs did not reveal any new predefined major finding. In only 5.8% of daily routine CXRs (14.3% of patients) was one or more new and unexpected abnormality encountered, including large atelectases (24 times in 20 patients), large infiltrates (23 in 22), severe pulmonary congestion (29 in 25), severe pleural effusion (13 in 13), pneumothorax/pneumomediastinum (14 in 13), and malposition of the orotracheal tube (32 in 26). Fewer than half of the CXRs with a new and unexpected finding were ultimately clinically relevant; in only 2.2% of all daily routine CXRs (6.4% of patients) did these radiologic abnormalities result in a change to therapy. Subgroup analysis revealed no differences between medical and surgical patients with regard to the incidence of new and unexpected findings on daily routine CXRs and the effect of new and unexpected CXR findings on daily care.
Conclusion
In the ICU, daily routine CXRs seldom reveal unexpected, clinically relevant abnormalities, and they rarely prompt action. We propose that this diagnostic examination be abandoned in ICU patients.
doi:10.1186/cc3955
PMCID: PMC1550788  PMID: 16420655
4.  Routine chest x-rays in intensive care units: a systematic review and meta-analysis 
Critical Care  2012;16(2):R68.
Introduction
Chest x-rays (CXRs) are the most frequent radiological tests performed in the intensive care unit (ICU). However, the utility of performing daily routine CXRs is unclear.
Methods
We searched Medline and Embase (1948 to March 2011) for randomized and quasi-randomized controlled trials (RCTs) and before-after observational studies comparing a strategy of routine CXRs to a more restrictive approach with CXRs performed to investigate clinical changes among critically ill adults or children. In duplicate, we extracted data on the CXR strategy, study quality and clinical outcomes (ICU and hospital mortality; duration of mechanical ventilation and ICU and hospital stay).
Results
Nine studies (39,358 CXRs; 9,611 patients) were included in the meta-analysis. Three trials (N = 870) of moderate to good quality provided information on the safety of a restrictive routine CXR strategy; only one trial systematically assessed for missed findings. Pooled data from trials showed no evidence of effect of a restrictive approach on ICU mortality (risk ratio [RR] 1.04, 95% confidence interval [CI] 0.84 to 1.28, P = 0.72; two trials, N = 776), hospital mortality (RR 0.98, 95% CI 0.68 to 1.41, P = 0.91; two trials, N = 259), ICU length of stay (weighted mean difference [WMD] -0.86 days, 95% CI -2.38 to 0.66 days, P = 0.27; three trials, N = 870), hospital length of stay (WMD -2.50 days, 95% CI -6.62 to 1.61 days, P = 0.23; two trials, N = 259), or duration of mechanical ventilation (WMD -0.30 days, 95% CI -1.48 to 0.89 days, P = 0.62; three trials, N = 705). Adding data from six observational studies, one of which systematically screened for missed findings, gave similar results.
Conclusions
This meta-analysis did not detect any harm associated with a restrictive chest radiograph strategy. However, confidence intervals were wide and harm was not rigorously assessed. Therefore, the safety of abandoning routine CXRs in patients admitted to the ICU remains uncertain.
doi:10.1186/cc11321
PMCID: PMC3681397  PMID: 22541022
5.  Significant changes in the practice of chest radiography in Dutch intensive care units: a web-based survey 
Background
ICU patients frequently undergo chest radiographs (CXRs). The diagnostic and therapeutic efficacy of routine CXRs are now known to be low, but the discussion regarding specific indications for CXRs in critically ill patients and the safety of abandoning routine CXRs is still ongoing. We performed a survey of Dutch intensivists on the current practice of chest radiography in their departments.
Methods
Web-based questionnaires, containing questions regarding ICU characteristics, ICU patients, daily CXR strategies, indications for routine CXRs and the practice of radiologic evaluation, were sent to the medical directors of all adult ICUs in the Netherlands. CXR strategies were compared between all academic and non-academic hospitals and between ICUs of different sizes. A comparison was made between the survey results obtained in 2006 and 2013.
Results
Of the 83 ICUs that were contacted, 69 (83%) responded to the survey. Only 7% of responding ICUs were currently performing daily routine CXRs for all patients, and 61% of the responding ICUs were said never to perform CXRs on a routine basis. A daily meeting with a radiologist is an established practice in 72% of the responding ICUs and is judged to be important or even essential by those ICUs. The therapeutic efficacy of routine CXRs was assumed by intensivists to be lower than 10% or to be between 10 and 20%. The efficacy of ‘on-demand’ CXRs was assumed to be between 10 and 60%. There is a consensus between intensivists to perform a routine CXR after endotracheal intubation, chest tube placement or central venous catheterization.
Conclusion
The strategy of daily routine CXRs for critically ill and mechanically ventilated patients has turned from being a common practice in 2006 to a rare current practice. Other routine strategies and an ‘on-demand only’ strategy have become more popular. Intensivists still assume the value of CXRs to be higher than the efficacy that is reported in the literature.
doi:10.1186/2110-5820-4-10
PMCID: PMC4113284  PMID: 24708581
Chest radiography; Imaging; Intensive care
6.  An integrated approach for prescribing fewer chest x-rays in the ICU 
Chest x-rays (CXRs) are the main imaging tool in intensive care units (ICUs). CXRs also are associated with concerns inherent to their use, considering both healthcare organization and patient perspectives. In recent years, several studies have focussed on the feasibility of lowering the number of bedside CXRs performed in the ICU. Such a decrease may result from two independent and complementary processes: a raw reduction of CXRs due to the elimination of unnecessary investigations, and replacement of the CXR by an alternative technique. The goal of this review is to outline emblematic examples corresponding to these two processes. The first part of the review concerns the accumulation of evidence-based data for abandoning daily routine CXRs in mechanically ventilated patients and adopting an on-demand prescription strategy. The second part of the review addresses the use of alternative techniques to CXRs. This part begins with the presentation of ultrasonography or capnography combined with epigastric auscultation for ensuring the correct position of enteral feeding tubes. Ultrasonography is then also presented as an alternative to CXR for diagnosing and monitoring pneumothoraces, as well as a valuable post-procedural technique after central venous catheter insertion. The combination of the emblematic examples presented in this review supports an integrated global approach for decreasing the number of CXRs ordered in the ICU.
doi:10.1186/2110-5820-1-4
PMCID: PMC3159900  PMID: 21906323
7.  Chest radiography in general practice: indications, diagnostic yield and consequences for patient management 
Background
Chest radiography (CXR) is frequently performed in Western societies. There is insufficient knowledge of its diagnostic value in terms of changes in patient management decisions in primary care.
Aim
To assess the influence of CXR on patient management in general practice.
Design of study
Prospective cohort study.
Setting
Seventy-eight GPs and three general hospitals in the Netherlands.
Method
Patients (n = 792) aged ≥18 years referred by their GPs for CXR were included. The main outcome was change in patient management assessed by means of questionnaires filled in by GPs before and after CXR.
Results
Mean age of the patients was 57.3±16.2 years and 53% were male. Clinically relevant abnormalities were found in 24% of the CXRs. Patient management changed in 60% of the patients following CXR. Main changes included: fewer referrals to a medical specialist (from 26 to 12%); reduction in initiation or change in therapy (from 24 to 15%); and more frequent reassurance (from 25 to 46%). However, this reassurance was not perceived as such in a quarter of these patients. A change in patient management occurred significantly more frequently in patients with complaints of cough (67%), those who exhibited abnormalities during physical examination (69%), or those with a suspected diagnosis of pneumonia (68%).
Conclusion
Patient management by the GP changed in 60% of patients following CXR. CXR substantially reduced the number of referrals and initiation or change in therapy, and more patients were reassured by their GP. Thus, CXR is an important diagnostic tool for GPs and seems a cost-effective diagnostic test.
PMCID: PMC1874520  PMID: 16882374
chest radiography; general practice; patient care management
8.  Utilization Effect of Integrating a Chest Radiography Room into a Thoracic Surgery Ward 
PURPOSE
Bedside chest radiography (bCXR) represents a substantial fraction of the volume of medical imaging for inpatient healthcare facilities. However, its image quality is limited compared to posterior-anterior/lateral (PA/LAT) acquisitions taken radiographic rooms. We evaluated utilization of bCXR and other chest imaging modalities before and after placing a radiography room within our thoracic surgical inpatient ward.
METHODS
Institutional review board approval was obtained for this HIPAA-compliant. We retrospectively identified all patient admissions (3,852) to the thoracic surgical units between April 1, 2007 and December 31, 2010. All chest imaging tests performed for these patients including computed tomography (CT) scans, magnetic resonance imaging (MRI), ultrasound (US), bedside and PA/LAT radiographs were counted. Our primary outcome measure was chest imaging utilization, defined as the number of chest examinations per admission, pre- and post-establishment of the digital radiography room on January, 10th 2010. Statistical analysis was performed using an independent-samples t-test to evaluate changes in chest imaging utilization.
RESULTS
We observed a 2.61 fold increase in the number of PA/LAT CXR per admission (p<0.01) and a 1.96 fold decrease in the number of bCXR per admission (p<0.01) post radiography room implementation. The number of chest CT, MRI and US per admission did not change significantly.
CONCLUSION
Establishing a radiography room physically within thoracic surgery units or in close proximity can significantly shift CXR utilization from bedside to PA/LAT acquisitions, which may enable opportunities for improvement in efficiency, quality, and safety in patient care.
doi:10.1016/j.jacr.2011.12.025
PMCID: PMC3361677  PMID: 22632669
Chest imaging; workflow improvement; imaging utilization; radiography room; radiology resource optimization
9.  Children with pneumonia: how do they present and how are they managed? 
Archives of Disease in Childhood  2007;92(5):394-398.
Objective
To describe the spectrum of clinical features and management of community acquired pneumonia in the UK.
Design
Prospectively recorded clinical details for all children with possible pneumonia and chest x ray (CXR) changes in 13 hospitals in the North of England between 2001 and 2002.
Results
89% of 711 children presenting to hospital with pneumonia were admitted; 96% received antibiotics, 70% intravenously. 20% had lobar CXR changes, 3% empyema and 4% required intensive care. Respiratory rate (RR), hypoxia and dyspnoea all correlated with each other and prompted appropriate interventions. Admission in children, not infants, was independently associated with RR, oxygen saturation, lobar CXR changes and pyrexia. Neither C‐reactive protein, lobar CXR changes or pyrexia were associated with severity. Children over 1 year old with perihilar CXR changes more often had severe disease (p = 0.001). Initial intravenous antibiotics were associated with lobar CXR changes in infants and children and with dyspnoea, pyrexia and pleural effusion in children. The presence of pleural effusion increased duration of antibiotic treatment (p<0.001). Cefuroxime was the most often used intravenous antibiotic in 61%. Oral antibiotics included a penicillin in 258 (46%), a macrolide in 192 (34%) and a cephalosporin in 117 (21%). Infants stayed significantly longer (p<0.001) as did children with severe disease (p<0.01), effusions (p = 0.005) or lobar CXR changes (p⩽0.001).
Conclusions
There is a high rate of intravenous antibiotic administration in hospital admissions for pneumonia. Despite lobar CXR changes not being independently associated with severe disease, initial lobar CXR changes and clinical assessment in children independently influenced management decisions, including admission and route of antibiotics.
doi:10.1136/adc.2006.097402
PMCID: PMC2083747  PMID: 17261579
community acquired pneumonia; childhood pneumonia; lobar pneumonia; severity; antibiotics
10.  The value of routine chest radiographs after minimally invasive cardiac surgery: an observational cohort study 
Background
Chest radiographs (CXRs) are obtained frequently in postoperative cardiac surgery patients. The diagnostic and therapeutic efficacy of routine CXRs is known to be low and the discussion regarding the safety of abandoning these CXRs after cardiac surgery is still ongoing. We investigated the value of routine CXRs directly after minimally invasive cardiac surgery.
Methods
We prospectively included all patients who underwent minimally invasive cardiac surgery by port access, ministernotomy or bilateral video-assisted thoracoscopy (VATS) in the year 2012. A direct postoperative CXR was performed on all patients at ICU arrival. All CXR findings were noted, including whether they led to an intervention or not. The results were compared to the postoperative CXR results in patients who underwent conventional cardiac surgery by full median sternotomy over the same period.
Main results
A total of 249 consecutive patients were included. Most of these patients underwent valve surgery, rhythm surgery or a combination of both. The diagnostic efficacy for minor findings was highest in the port access and bilateral VATS groups (56% and 63% versus 28% and 45%) (p < 0.005). The diagnostic efficacy for major findings was also higher in these groups (8.9% and 11% versus 4.3% and 3.8%) (p = 0.010). The need for an intervention was most common after minimally invasive surgery by port access, although this difference was not statistically significant (p = 0.056).
Conclusions
The diagnostic efficacy of routine CXRs performed after minimally invasive cardiac surgery by port access or bilateral VATS is higher than the efficacy of CXRs performed after conventional cardiac surgery. A routine CXR after these procedures should still be considered.
doi:10.1186/s13019-014-0174-9
PMCID: PMC4232684  PMID: 25385274
Chest radiographs; Cardiac surgery; Intensive care unit
11.  Impact of Post-Intubation Interventions on Mortality in Patients Boarding in the Emergency Department 
Introduction
Emergency physicians frequently perform endotracheal intubation and mechanical ventilation. The impact of instituting early post-intubation interventions on patients boarding in the emergency department (ED) is not well studied. We sought to determine the impact of post-intubation interventions (arterial blood gas sampling, obtaining a chest x-ray (CXR), gastric decompression, early sedation, appropriate initial tidal volume, and quantitative capnography) on outcomes of mortality, ventilator-associated pneumonia (VAP), ventilator days, and intensive care unit (ICU) length-of-stay (LOS).
Methods
This was an observational, retrospective study of patients intubated in the ED at a large tertiary-care teaching hospital and included patients in the ED for greater than two hours post-intubation. We excluded them if they had incomplete data, were designated “do not resuscitate,” were managed primarily by the trauma team, or had surgery within six hours after intubation.
Results
Of 169 patients meeting criteria, 15 died and 10 developed VAP. The mortality odds ratio (OR) in patients receiving CXR was 0.10 (95% CI 0.01 to 0.98), and 0.11 (95% CI 0.03 to 0.46) in patients receiving early sedation. The mortality OR for patients with 3 or fewer interventions was 4.25 (95% CI 1.15 to 15.75) when compared to patients with 5 or more interventions. There was no significant relationship between VAP rate, ventilator days, or ICU LOS and any of the intervention groups.
Conclusion
The performance of a CXR and early sedation as well as performing five or more vs. three or fewer post-intubation interventions in boarding adult ED patients was associated with decreased mortality.
doi:10.5811/westjem.2014.7.22292
PMCID: PMC4162735  PMID: 25247049
12.  The interrelations of radiologic findings and mechanical ventilation in community acquired pneumonia patients admitted to the intensive care unit: a multicentre retrospective study 
Background
We evaluated patients admitted to the intensive care units with the diagnosis of community acquired pneumonia (CAP) regarding initial radiographic findings.
Methods
A multicenter retrospective study was held. Chest x ray (CXR) and computerized tomography (CT) findings and also their associations with the need of ventilator support were evaluated.
Results
A total of 388 patients were enrolled. Consolidation was the main finding on CXR (89%) and CT (80%) examinations. Of all, 45% had multi-lobar involvement. Bilateral involvement was found in 40% and 44% on CXR and CT respectively. Abscesses and cavitations were rarely found. The highest correlation between CT and CXR findings was observed for interstitial involvement. More than 80% of patients needed ventilator support. Noninvasive mechanical ventilation (NIV) requirement was seen to be more common in those with multi-lobar involvement on CXR as 2.4-fold and consolidation on CT as 47-fold compared with those who do not have these findings. Invasive mechanical ventilation (IMV) need increased 8-fold in patients with multi-lobar involvement on CT.
Conclusion
CXR and CT findings correlate up to a limit in terms of interstitial involvement but not in high percentages in other findings. CAP patients who are admitted to the ICU are severe cases frequently requiring ventilator support. Initial CT and CXR findings may indicate the need for ventilator support, but the assumed ongoing real practice is important and the value of radiologic evaluation beyond clinical findings to predict the mechanical ventilation need is subject for further evaluation with large patient series.
doi:10.1186/1476-0711-13-5
PMCID: PMC3898785  PMID: 24400646
Radiography; Thoracic; Pneumoniae; Imaging; Critical care
13.  Automated identification of pneumonia in chest radiograph reports in critically ill patients 
Background
Prior studies demonstrate the suitability of natural language processing (NLP) for identifying pneumonia in chest radiograph (CXR) reports, however, few evaluate this approach in intensive care unit (ICU) patients.
Methods
From a total of 194,615 ICU reports, we empirically developed a lexicon to categorize pneumonia-relevant terms and uncertainty profiles. We encoded lexicon items into unique queries within an NLP software application and designed an algorithm to assign automated interpretations (‘positive’, ‘possible’, or ‘negative’) based on each report’s query profile. We evaluated algorithm performance in a sample of 2,466 CXR reports interpreted by physician consensus and in two ICU patient subgroups including those admitted for pneumonia and for rheumatologic/endocrine diagnoses.
Results
Most reports were deemed ‘negative’ (51.8%) by physician consensus. Many were ‘possible’ (41.7%); only 6.5% were ‘positive’ for pneumonia. The lexicon included 105 terms and uncertainty profiles that were encoded into 31 NLP queries. Queries identified 534,322 ‘hits’ in the full sample, with 2.7 ± 2.6 ‘hits’ per report. An algorithm, comprised of twenty rules and probability steps, assigned interpretations to reports based on query profiles. In the validation set, the algorithm had 92.7% sensitivity, 91.1% specificity, 93.3% positive predictive value, and 90.3% negative predictive value for differentiating ‘negative’ from ‘positive’/’possible’ reports. In the ICU subgroups, the algorithm also demonstrated good performance, misclassifying few reports (5.8%).
Conclusions
Many CXR reports in ICU patients demonstrate frank uncertainty regarding a pneumonia diagnosis. This electronic tool demonstrates promise for assigning automated interpretations to CXR reports by leveraging both terms and uncertainty profiles.
doi:10.1186/1472-6947-13-90
PMCID: PMC3765332  PMID: 23947340
Pneumonia; Intensive care unit; Natural language processing; Chest imaging; Electronic tool
14.  Is routine chest radiography indicated following chest drain removal after cardiothoracic surgery? 
A best evidence topic was written according to a structured protocol. The question addressed was whether routine chest radiography is indicated following chest drain removal in patients undergoing cardiothoracic surgery. A total of 356 papers were found using the reported searches; of which, 6 represented the best evidence to answer the clinical question. The authors, date, journal, study type, population, main outcome measures and results are tabulated. Reported measures were mean duration of drains left in situ, timing of drain removal, pathology detected on chest radiographs (CXRs), interventions following imaging and clinical assessment, complications in patients not undergoing routine CXRs and the cost saving of omitting routine CXRs. One large cohort study reported the detection of pathology in 79% of clinically indicated CXRs in comparison to 40% of routine CXRs (P = 0.005). Ninety-five per cent of the non-routine CXR cohort remained asymptomatic and required no intervention. One large observational study reported the detection of new pneumothoraces in 9.3% of patients, 70.3% of which were barely perceptible. Intervention following CXR was required in 0.25% and only one medium-sized pneumothorax would have been potentially missed without CXR. Another large observational study reported intervention following CXR in 1.9% and the presence of relevant clinical signs and symptoms to be a significant predictor of major intervention (P < 0.01). A smaller observational study reported no pathology detected or intervention following CXR in 98% and the cost saving of omitting a single CXR at £10 000 per annum. Another small observational study reported only 7% of CXRs to be clinically indicated with a false-positive rate of 100%, and a false-negative rate of 7% in CXRs not clinically indicated. The smallest study reported no complications in the non-CXR cohort and only one patient undergoing intervention in the routine CXR cohort. We conclude that there is evidence that routine post drain removal CXR provides no diagnostic or therapeutic advantage over clinically indicated CXR or simple clinical assessment. The best evidence studies reported the detection of pathology on routine CXR ranging from 2 to 40% compared with 79% in clinically indicated CXRs (P = 0.005). Whilst the rate of intervention following routine CXR was as high as 4% in the smallest study, clinical signs and symptoms suggestive of pathology were a significant predictor of major re-intervention (P < 0.01).
doi:10.1093/icvts/ivs037
PMCID: PMC3352714  PMID: 22392935
Chest drain; Chest radiography
15.  Erect chest radiography in the setting of the acute abdomen: essential tool or an unnecessary waste of resources? 
INTRODUCTION
It has been suggested that changes to the training schemes of junior doctors and the increased pressure on emergency departments to manage their patients within a limited time might increase the number of unnecessary investigations performed on emergency admission patients. This, in turn, may lead to an increased number of investigations with normal results. In this study we try to analyse the role of the chest X-ray (CXR) as a diagnostic tool in patients presenting with acute abdominal pain.
PATIENTS AND METHODS
A retrospective study was performed of the request forms and results of all chest radiography performed on patients admitted on the emergency surgical intake with acute abdominal pain through utilisation of the prospec-tively maintained electronic radiology database. The indications were compared to the guidelines published by the Royal College of Radiologists (RCR) which have been adopted as the standard of care.
RESULTS
A total of 334 chest X-rays were identified of which only 23 (7%) had new findings. Four (1%) patients had free gas under the diaphragm. Of the CXRs, 258 (77%) were reported normal whilst 53 (16%) had old changes which were described in their hospital records and previous radiographs. Of the CXRs with new findings, only 20 were clinically significant and, of these, four (1%) were surgically significant.
CONCLUSIONS
The majority of CXRs performed on emergency surgical admissions with abdominal pain are unnecessary. By obtaining a clear history, performing a thorough clinical examination and following the RCR guidelines most of the CXRs could be avoided. This would lead to less radiation exposure, reduce delays to diagnosis, and provide significant financial savings.
doi:10.1308/003588410X12699663904998
PMCID: PMC3229383  PMID: 20650038
Chest radiograph; Acute abdomen
16.  Validation Study of an Automated Electronic Acute Lung Injury Screening Tool 
Objective
The authors designed an automated electronic system that incorporates data from multiple hospital information systems to screen for acute lung injury (ALI) in mechanically ventilated patients. The authors evaluated the accuracy of this system in diagnosing ALI in a cohort of patients with major trauma, but excluding patients with congestive heart failure (CHF).
Design
Single-center validation study. Arterial blood gas (ABG) data and chest radiograph (CXR) reports for a cohort of intensive care unit (ICU) patients with major trauma but excluding patients with CHF were screened prospectively for ALI requiring intubation by an automated electronic system. The system was compared to a reference standard established through consensus of two blinded physician reviewers who independently screened the same population for ALI using all available ABG data and CXR images. The system's performance was evaluated (1) by measuring the sensitivity and overall accuracy, and (2) by measuring concordance with respect to the date of ALI identification (vs. reference standard).
Measurements
One hundred ninety-nine trauma patients admitted to our level 1 trauma center with an initial injury severity score (ISS) ≥ 16 were evaluated for development of ALI in the first five days in an ICU after trauma.
Main Results
The system demonstrated 87% sensitivity (95% confidence interval [CI] 82.3–91.7) and 89% specificity (95% CI 84.7–93.4). It identified ALI before or within the 24-hour period during which ALI was identified by the two reviewers in 87% of cases.
Conclusions
An automated electronic system that screens intubated ICU trauma patients, excluding patients with CHF, for ALI based on CXR reports and results of ABGs is sufficiently accurate to identify many early cases of ALI.
doi:10.1197/jamia.M3120
PMCID: PMC2705253  PMID: 19390095
17.  Chest X-ray and electrocardiogram in post-cardiac surgery follow-up clinics: should this be offered routinely or when clinically indicated? 
OBJECTIVES
Many centres in the UK carry out routine chest X-ray (CXR) and/or electrocardiogram (ECG) when patients attend follow-up clinic after cardiac surgery. Current evidence to support this practice is weak. This study investigated the appropriateness of carrying out these investigations in the absence of clinical indication.
METHODS
All patients attending routine 6- to 8-week follow-up clinic after cardiac surgery in this hospital were prospectively reviewed over a 6-month period (October 2011–April 2012). Two groups were identified for comparison. Group A comprised patients who had CXR and/or ECG requested routinely, and those in Group B had the investigations only when clinically indicated. A proforma was designed to screen each patient for cardiac and respiratory symptoms, predischarge CXR abnormalities and the presence of atrial fibrillation/flutter postoperatively. Management alterations based on the findings from the investigations were noted. Patients who had thoracic, major aortic, or heart transplant surgery were excluded from the audit.
RESULTS
Three hundred and fifty patients were reviewed: 250 were in Group A and 100 in Group B. No patient had a significant management alteration in the absence of an indication for the tests. There were no differences in outcome between the two groups. In Group A, 111 (45%) patients had CXR and ECG done without indication and no abnormality was detected. In Group B, 52 patients had no indication for either tests and were thus not tested. None of these patients required readmission/intervention following discharge from clinic. Overall, 271 patients had CXR carried out, with only 83 being indicated. This led to a management alteration in 33 patients (12% overall, 40% if indicated). Two hundred and eighty-six patients had ECG carried out with 140 indicated. Management was altered in 122 patients (43% overall, 87% if indicated). The correlation between the clinical indication-based investigation and the resulting change in patient management was found to be significant (Goodman–Kruskal Gamma: 0.99, P = 0.000 for both investigations).
CONCLUSIONS
There is a strong correlation between clinical indication for CXR and/or ECG and management alterations. These investigations should be performed during the routine follow-up of adult cardiac surgical patients using a patient-centred approach based on signs and symptoms.
doi:10.1093/icvts/ivt017
PMCID: PMC3653455  PMID: 23429568
Cardiac surgery; Postoperative clinic; Chest X-ray; Electrocardiogram; NHS funding
18.  High Discordance of Chest X-ray and CT for Detection of Pulmonary Opacities in ED Patients: Implications for Diagnosing Pneumonia 
Objective
To evaluate the diagnostic performance of chest x-ray (CXR) compared to computed tomography (CT) for detection of pulmonary opacities in adult emergency department (ED) patients.
Methods
We conducted an observational cross sectional study of adult patients presenting to 12 EDs in the United States from July 1, 2003 through November 30, 2006 who underwent both CXR and chest CT for routine clinical care. CXRs and CT scans performed on the same patient were matched. CXRs and CT scans were interpreted by attending radiologists and classified as containing pulmonary opacities if the final radiologist report noted opacity, infiltrate, consolidation, pneumonia, or bronchopneumonia. Using CT as a criterion standard, the diagnostic test characteristics of CXR to detect pulmonary opacities were calculated.
Results
The study cohort included 3,423 patients. Shortness of breath, chest pain and cough were the most common complaints, with 96.1% of subjects reporting at least one of these symptoms. Pulmonary opacities were visualized on 309 (9.0%) CXRs and 191 (5.6 %) CT scans. CXR test characteristics for detection of pulmonary opacities included: sensitivity 43.5% (95% CI: 36.4%–50.8%); specificity 93.0% (95% CI: 92.1%–93.9%); positive predictive value 26.9% (95% CI: 22.1%–32.2%); and negative predictive value 96.5% (95% CI: 95.8%–97.1%).
Conclusion
In this multicenter cohort of adult ED patients with acute cardiopulmonary symptoms, CXR demonstrated poor sensitivity and positive predictive value for detecting pulmonary opacities. Reliance on CXR to identify pneumonia may lead to significant rates of misdiagnosis.
doi:10.1016/j.ajem.2012.08.041
PMCID: PMC3556231  PMID: 23083885
chest x-ray; computed tomography; pneumonia; emergency department; diagnostic testing
19.  Pulmonary imaging of pandemic influenza H1N1 infection: relationship between clinical presentation and disease burden on chest radiography and CT 
The British Journal of Radiology  2010;83(992):645-651.
The potential for pulmonary involvement among patients presenting with novel swine-origin influenza A (H1N1) is high. To investigate the utility of chest imaging in this setting, we correlated clinical presentation with chest radiographic and CT findings in patients with proven H1N1 cases. Subjects included all patients presenting with laboratory-confirmed H1N1 between 1 May and 10 September 2009 to one of three urban hospitals. Clinical information was gathered retrospectively, including symptoms, possible risk factors, treatment and hospital survival. Imaging studies were re-read for study purposes, and CXR findings compared with CT scans when available. During the study period, 157 patients presented with subsequently proven H1N1 infection. Hospital admission was necessary for 94 (60%) patients, 16 (10%) were admitted to intensive care and 6 (4%) died. An initial CXR, carried out for 123 (78%) patients, was abnormal in only 40 (33%) cases. Factors associated with increased likelihood for radiographic lung abnormalities were dyspnoea (p<0.001), hypoxaemia (p<0.001) and diabetes mellitus (p = 0.023). Chest CT was performed in 21 patients, and 19 (90%) showed consolidation, ground-glass opacity, nodules or a combination of these findings. 4 of 21 patients had negative CXR and positive CT. Compared with CT, plain CXR was less sensitive in detecting H1N1 pulmonary disease among immunocompromised hosts than in other patients (p = 0.0072). A normal CXR is common among patients presenting to the hospital for H1N1-related symptoms without evidence of respiratory difficulties. The CXR may significantly underestimate lung involvement in the setting of immunosuppression.
doi:10.1259/bjr/53692814
PMCID: PMC3473510  PMID: 20551254
20.  The role and performance of chest X-ray for the diagnosis of tuberculosis: A cost-effectiveness analysis in Nairobi, Kenya 
Background
The objective of this study was to establish 1) the performance of chest X-ray (CXR) in all suspects of tuberculosis (TB), as well as smear-negative TB suspects and 2) to compare the cost-effectiveness of the routine diagnostic pathway using Ziehl-Neelsen (ZN) sputum microscopy followed by CXR if case of negative sputum result (ZN followed by CXR) with an alternative pathway using CXR as a screening tool (CXR followed by ZN).
Methods
From TB suspects attending a chest clinic in Nairobi, Kenya, three sputum specimens were examined for ZN and culture (Lowenstein Jensen). Culture was used as gold standard. From each suspect a CXR was made using a four point scoring system: i: no pathology, ii: pathology not consistent for TB, iii: pathology consistent for TB and iv: pathology highly consistent for TB. The combined score i + ii was labeled as "no TB" and the combined score iii + iv was labeled as "TB". Films were re-read by a reference radiologist. HIV test was performed on those who consented. Laboratory and CXR costs were used to compare for cost-effectiveness.
Results
Of the 1,389 suspects enrolled, for 998 (72%) data on smear, culture and CXR was complete. 714 films were re-read, showing a 89% agreement (kappa value = 0.75 s.e.0.037) for the combined scores "TB" or "no-TB". The sensitivity/specificity of the CXR score "TB" among smear-negative suspects was 80%/67%. Using chest CXR as a screening tool in all suspects, sensitivity/specificity of the score "any pathology" was 92%, respectively 63%. The cost per correctly diagnosed case was for the routine process $8.72, compared to $9.27 using CXR as screening tool. When costs of treatment were included, CXR followed by ZN became more cost-effective.
Conclusion
The diagnostic pathway ZN followed by CXR was more cost-effective as compared to CXR followed by ZN. When cost of treatment was also considered CXR followed by ZN became more cost-effective. The low specificity of chest X-ray remains a subject of concern. Depending whether CXR was performed on all suspects or on smear-negative suspects only, 22%–45% of patients labeled as "TB" had a negative culture. The introduction of a well-defined scoring system, clinical conferences and a system of CXR quality control can contribute to improved diagnostic performance.
doi:10.1186/1471-2334-5-111
PMCID: PMC1326228  PMID: 16343340
21.  A national survey of the diagnosis and management of suspected ventilator-associated pneumonia 
BMJ Open Respiratory Research  2014;1(1):e000066.
Background
Ventilator-associated pneumonia (VAP) affects up to 20% of patients admitted to intensive care units (ICU). It is associated with increased morbidity, mortality and healthcare costs. Despite published guidelines, variability in diagnosis and management exists, the extent of which remains unclear. We sought to characterise consultant opinions surrounding diagnostic and management practice for VAP in the UK.
Methods
An online survey was sent to all consultant members of the UK Intensive Care Society (n=∼1500). Data were collected regarding respondents’ individual practice in the investigation and management of suspected VAP including use of diagnostic criteria, microbiological sampling, chest X-ray (CXR), bronchoscopy and antibiotic treatments.
Results
339 (23%) responses were received from a broadly representative spectrum of ICU consultants. All respondents indicated that microbiological confirmation should be sought, the majority (57.8%) stating they would take an endotracheal aspirate prior to starting empirical antibiotics. Microbiology reporting services were described as qualitative only by 29.7%. Only 17% of respondents had access to routine reporting of CXRs by a radiologist. Little consensus exists regarding technique for bronchoalveolar lavage (BAL) with the reported volume of saline used ranging from 5 to 500 mL. 24.5% of consultants felt inadequately trained in bronchoscopy.
Conclusions
There is wide variability in the approach to diagnosis and management of VAP among UK consultants. Such variability challenges the reliability of the diagnosis of VAP and its reported incidence as a performance indicator in healthcare systems. The data presented suggest increased radiological and microbiological support, and standardisation of BAL technique, might improve this situation.
doi:10.1136/bmjresp-2014-000066
PMCID: PMC4275666  PMID: 25553248
Respiratory Infection; Pneumonia; Assisted Ventilation
22.  Is a postintubation chest radiograph necessary in the emergency department? 
Background
Postintubation chest X-rays (CXR) are standard practice in emergency department (ED) intubations. In the operating room, it is not usually a standard practice to confirm endotracheal tube placement with a CXR.
Aims
We seek to study the utility of postintubation CXR in ED patients.
Methods
This was a retrospective case series of 157 adult patients intubated in the ED of an urban academic hospital with an emergency medicine training program. Standardized chart review was performed by two emergency physicians (EP) using a structured data abstraction tool and final radiology attending reads of postintubation CXR to assess placement. Endotracheal tube placement was graded as satisfactory, too high, too low, or malpositioned in the esophagus. Descriptive statistics were used, and 95% confidence intervals (CI) were reported. Hospital Institutional Review Board approval was obtained.
Results
A total of 157 patients were intubated in the ED during the study period: 127 (81%, 95% CI: 74–86) had adequate tube placement by CXR confirmation, 9 (6%, 95% CI: 3–11) endotracheal tubes were judged to be too high, and 20 (13%, 95% CI: 8–19) were judged to be too low with 10 (6.5%, 95% CI: 3–11) of these being right mainstem bronchus intubations. One patient (<1%, 95% CI:<0.0001–4) had a CXR confirming esophageal intubation.
Conclusion
ED intubations were judged to have “satisfactory” placement by CXR in 81% of patients. CXR is able to identify a small subset of patients that likely need immediate intervention based on their CXR. Until further studies refute the utility of postintubation CXR in ED intubations, they should remain a part of routine practice.
doi:10.1007/s12245-009-0133-8
PMCID: PMC2840601  PMID: 20436895
Intubation; Chest X-ray; Emergency department
23.  Circulating Mitochondrial DNA in Patients in the ICU as a Marker of Mortality: Derivation and Validation 
PLoS Medicine  2013;10(12):e1001577.
In this paper, Choi and colleagues analyzed levels of mitochondrial DNA in two prospective observational cohort studies and found that increased mtDNA levels are associated with ICU mortality, and improve risk prediction in medical ICU patients. The data suggests that mtDNA could serve as a viable plasma biomarker in MICU patients.
Background
Mitochondrial DNA (mtDNA) is a critical activator of inflammation and the innate immune system. However, mtDNA level has not been tested for its role as a biomarker in the intensive care unit (ICU). We hypothesized that circulating cell-free mtDNA levels would be associated with mortality and improve risk prediction in ICU patients.
Methods and Findings
Analyses of mtDNA levels were performed on blood samples obtained from two prospective observational cohort studies of ICU patients (the Brigham and Women's Hospital Registry of Critical Illness [BWH RoCI, n = 200] and Molecular Epidemiology of Acute Respiratory Distress Syndrome [ME ARDS, n = 243]). mtDNA levels in plasma were assessed by measuring the copy number of the NADH dehydrogenase 1 gene using quantitative real-time PCR. Medical ICU patients with an elevated mtDNA level (≥3,200 copies/µl plasma) had increased odds of dying within 28 d of ICU admission in both the BWH RoCI (odds ratio [OR] 7.5, 95% CI 3.6–15.8, p = 1×10−7) and ME ARDS (OR 8.4, 95% CI 2.9–24.2, p = 9×10−5) cohorts, while no evidence for association was noted in non-medical ICU patients. The addition of an elevated mtDNA level improved the net reclassification index (NRI) of 28-d mortality among medical ICU patients when added to clinical models in both the BWH RoCI (NRI 79%, standard error 14%, p<1×10−4) and ME ARDS (NRI 55%, standard error 20%, p = 0.007) cohorts. In the BWH RoCI cohort, those with an elevated mtDNA level had an increased risk of death, even in analyses limited to patients with sepsis or acute respiratory distress syndrome. Study limitations include the lack of data elucidating the concise pathological roles of mtDNA in the patients, and the limited numbers of measurements for some of biomarkers.
Conclusions
Increased mtDNA levels are associated with ICU mortality, and inclusion of mtDNA level improves risk prediction in medical ICU patients. Our data suggest that mtDNA could serve as a viable plasma biomarker in medical ICU patients.
Please see later in the article for the Editors' Summary
Editors' Summary
Background
Intensive care units (ICUs, also known as critical care units) are specialist hospital wards that provide care for people with life-threatening injuries and illnesses. In the US alone, more than 5 million people are admitted to ICUs every year. Different types of ICUs treat different types of problems. Medical ICUs treat patients who, for example, have been poisoned or who have a serious infection such as sepsis (blood poisoning) or severe pneumonia (inflammation of the lungs); trauma ICUs treat patients who have sustained a major injury; cardiac ICUs treat patients who have heart problems; and surgical ICUs treat complications arising from operations. Patients admitted to ICUs require constant medical attention and support from a team of specially trained nurses and physicians to prevent organ injury and to keep their bodies functioning. Monitors, intravenous tubes (to supply essential fluids, nutrients, and drugs), breathing machines, catheters (to drain urine), and other equipment also help to keep ICU patients alive.
Why Was This Study Done?
Although many patients admitted to ICUs recover, others do not. ICU specialists use scoring systems (algorithms) based on clinical signs and physiological measurements to predict their patients' likely outcomes. For example, the APACHE II scoring system uses information on heart and breathing rates, temperature, levels of salts in the blood, and other signs and physiological measurements collected during the first 24 hours in the ICU to predict the patient's risk of death. Existing scoring systems are not perfect, however, and “biomarkers” (molecules in bodily fluids that provide information about a disease state) are needed to improve risk prediction for ICU patients. Here, the researchers investigate whether levels of circulating cell-free mitochondrial DNA (mtDNA) are associated with ICU deaths and whether these levels can be used as a biomarker to improve risk prediction in ICU patients. Mitochondria are cellular structures that produce energy. Levels of mtDNA in the plasma (the liquid part of blood) increase in response to trauma and infection. Moreover, mtDNA activates molecular processes that lead to inflammation and organ injury.
What Did the Researchers Do and Find?
The researchers measured mtDNA levels in the plasma of patients enrolled in two prospective observational cohort studies that monitored the outcomes of ICU patients. In the Brigham and Women's Hospital Registry of Critical Illness study, blood was taken from 200 patients within 24 hours of admission into the hospital's medical ICU. In the Molecular Epidemiology of Acute Respiratory Distress Syndrome study (acute respiratory distress syndrome is a life-threatening inflammatory reaction to lung damage or infection), blood was taken from 243 patients within 48 hours of admission into medical and non-medical ICUs at two other US hospitals. Patients admitted to medical ICUs with a raised mtDNA level (3,200 or more copies of a specific mitochondrial gene per microliter of plasma) had a 7- to 8-fold increased risk of dying within 28 days of admission compared to patients with mtDNA levels of less than 3,200 copies/µl plasma. There was no evidence of an association between raised mtDNA levels and death among patients admitted to non-medical ICUs. The addition of an elevated mtDNA level to a clinical model for risk prediction that included the APACHE II score and biomarkers that are already used to predict ICU outcomes improved the net reclassification index (an indicator of the improvement in risk prediction algorithms offered by new biomarkers) of 28-day mortality among medical ICU patients in both studies.
What Do These Findings Mean?
These findings indicate that raised mtDNA plasma levels are associated with death in medical ICUs and show that, among patients in medical ICUs, measurement of mtDNA plasma levels can improve the prediction of the risk of death from the APACHE II scoring system, even when commonly measured biomarkers are taken into account. These findings do not indicate whether circulating cell-free mtDNA increased because of the underlying severity of illness or whether mtDNA actively contributes to the disease process in medical ICU patients. Moreover, they do not provide any evidence that raised mtDNA levels are associated with an increased risk of death among non-medical (mainly surgical) ICU patients. These findings need to be confirmed in additional patients, but given the relative ease and rapidity of mtDNA measurement, the determination of circulating cell-free mtDNA levels could be a valuable addition to the assessment of patients admitted to medical ICUs.
Additional Information
Please access these websites via the online version of this summary at http://dx.doi.org/10.1371/journal.pmed.1001577.
The UK National Health Service Choices website provides information about intensive care
The Society of Critical Care Medicine provides information for professionals, families, and patients about all aspects of intensive care
MedlinePlus provides links to other resources about intensive care (in English and Spanish)
The UK charity ICUsteps supports patients and their families through recovery from critical illness; its booklet Intensive Care: A Guide for Patients and Families is available in English and ten other languages; its website includes patient experiences and relative experiences of treatment in ICUs
Wikipedia has a page on ICU scoring systems (note that Wikipedia is a free online encyclopedia that anyone can edit; available in several languages)
doi:10.1371/journal.pmed.1001577
PMCID: PMC3876981  PMID: 24391478
24.  Comparison of thermodilution measured extravascular lung water with chest radiographic assessment of pulmonary oedema in patients with acute lung injury 
Background
Acute lung injury and the acute respiratory distress syndrome (ALI/ARDS) are characterized by pulmonary oedema, measured as extravascular lung water (EVLW). The chest radiograph (CXR) can potentially estimate the quantity of lung oedema while the transpulmonary thermodilution method measures the amount of EVLW. This study was designed to determine whether EVLW as estimated by a CXR score predicts EVLW measured by the thermodilution method and whether changes in EVLW by either approach predict mortality in ALI/ARDS.
Methods
Clinical data were collected within 48 hours of ALI/ARDS diagnosis and daily up to 14 days on 59 patients with ALI/ARDS. Two clinicians scored each CXR for the degree of pulmonary oedema, using a validated method. EVLW indexed to body weight was measured using the single indicator transpulmonary thermodilution technique.
Results
The CXR score had a modest, positive correlation with the EVLWI measurements (r = 0.35, p < 0.001). There was a 1.6 ml/kg increase in EVLWI per 10-point increase in the CXR score (p < 0.001, 95% confidence interval 0.92-2.35). The sensitivity of a high CXR score for predicting a high EVLWI was 93%; similarly the negative predictive value was high at 94%; the specificity (51%) and positive predictive value (50%) were lower. The CXR scores did not predict mortality but the EVLW thermodilution did predict mortality.
Conclusion
EVLW measured by CXR was modestly correlated with thermodilution measured EVLW. Unlike CXR findings, transpulmonary thermodilution EVLWI measurements over time predicted mortality in patients with ALI/ARDS.
doi:10.1186/2110-5820-3-25
PMCID: PMC3846630  PMID: 23937970
Extravascular lung water; Chest radiograph; Acute lung injury; Acute respiratory distress syndrome
25.  Chest radiography findings in adults with pandemic H1N1 2009 influenza 
The British Journal of Radiology  2010;83(990):499-504.
The current pandemic of a novel influenza A (H1N1) virus, commonly referred to as “swine flu”, began in Mexico in March 2009 and reached the UK in April 2009. By 21 July 2009, more than 850 suspected cases of influenza had been seen at Birmingham Heartlands Hospital (BHH), including 52 adults with laboratory-confirmed pandemic H1N1 influenza who were admitted. Of seven patients (13%) requiring intensive care, six needed mechanical ventilation, two needed extra-corporeal membrane oxygenation (ECMO) and one died. Of the 52 admitted adults, 42 (81%) had respiratory symptoms or signs and positive PCR tests for novel Influenza A (H1N1) virus. These patients also had chest radiographs (CXR) taken, which were abnormal for 12 patients (29%). Of these, six patients had bilateral consolidation, which was bibasal in three and widespread in three; all six had pleural effusions. A further six patients had unilateral consolidation with predominantly basal changes; one of these patients had a pleural effusion. The odds ratio for requiring intubation and ventilation with H1N1 influenza and an abnormal CXR was 29.0 (95% confidence interval 2.93–287.0). CXR changes were not common in swine flu, but a significant minority of those requiring admission had consolidation on their CXR. Those who required admission and had CXR changes are more likely to require intubation and ventilation than those without abnormalities on CXR.
doi:10.1259/bjr/24252450
PMCID: PMC3473598  PMID: 20505030

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