InfectionAccuracy of the chest radiograph to identify bilateral pulmonary infiltrates consistent with the diagnosis of acute respiratory distress syndrome using computed tomography as reference standard☆
Introduction
The presence of bilateral infiltrates on an anteroposterior chest radiograph is a necessary criterion for the diagnosis of acute respiratory distress syndrome (ARDS) by recommendation of the American-European Consensus Conference (AECC) in ARDS [1]. This definition has been the most commonly used in clinical practice and in epidemiologic [2] and other research studies with important clinical implications [3], [4], [5], [6]. However, this radiographic criterion is not precise and can result in significant interobserver variability [7], [8], [9] or equivocal interpretation [10]. The recent Berlin definition of ARDS, likely to be widely used in the future, recommends a similar radiographic criterion of bilateral opacities [11]. Those limitations to the radiographic criterion may have important implications in the correct selection of patients for research studies and in the appropriate diagnosis and consequent application of therapies in clinical practice.
This study aims to evaluate the accuracy of the anteroposterior chest radiograph to detect pulmonary abnormalities consistent with ARDS in patients who may have the syndrome, using chest computed tomography (CT) as reference standard. We conducted a comparison between chest radiograph and chest CT in patients meeting criteria for ARDS regardless of the radiographic one.
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Subjects
Subjects were retrospectively selected from patients admitted to a 30-bed adult medical-surgical-trauma intensive care unit (ICU) of a university hospital between March 2009 and October 2011. The selection was performed using initially the hospital radiology computerized database and further refined by review of the subjects' medical records by an intensivist. Informed consent was waived by the local institutional review board given the nature of the study and that data were collected without
Results
Ninety subjects were identified meeting inclusion but no exclusion criteria. Ninety-seven percent were receiving invasive mechanical ventilation. The subjects' characteristics on the day the analyzed images were performed are summarized in Table 1.
There was disagreement between the 2 radiologists in the interpretation of the chest radiograph in 29 subjects. In 25 subjects, the disagreement included possible bilateral findings, whereas in 4 subjects, the disagreement was between unilateral vs
Discussion
By comparing portable chest radiographs with chest CT (as reference standard) in patients meeting criteria for ARDS regardless of the radiographic one, this study shows the limited accuracy of the radiographic criterion of the definition of ARDS. For the detection of “bilateral pulmonary infiltrates or opacities” consistent with the diagnosis of ARDS, we found the chest radiograph to have only fair interobserver agreement [14] between 2 radiologists and, after resolution of disagreements, an
References (26)
- et al.
Interobserver variability in applying a radiographic definition for ARDS
Chest
(1999) - et al.
An alternative method of acute lung injury classification for use in observational studies
Chest
(2010) - et al.
Development of a clinical definition for acute respiratory distress syndrome using the Delphi technique
J Crit Care
(2005) - et al.
The role of CT-scan studies for the diagnosis and therapy of acute respiratory distress syndrome
Clin Chest Med
(2006) - et al.
The American-European Consensus Conference on ARDS. Definitions, mechanisms, relevant outcomes, and clinical trial coordination
Am J Respir Crit Care Med
(1994) - et al.
The ALIEN study: incidence and outcome of acute respiratory distress syndrome in the era of lung protective ventilation
Intensive Care Med
(2012) - et al.
Higher vs lower positive end-expiratory pressure in patients with acute lung injury and acute respiratory distress syndrome
JAMA
(2010) Ventilation with lower tidal volumes as compared with traditional tidal volumes for acute lung injury and the acute respiratory distress syndrome
N Engl J Med
(2000)Higher versus lower positive end-expiratory pressures in patients with the acute respiratory distress syndrome
N Engl J Med
(2004)- et al.
A high positive end-expiratory pressure, low tidal volume ventilatory strategy improves outcome in persistent acute respiratory distress syndrome: a randomized, controlled trial
Crit Care Med
(2006)
Interobserver variation in interpreting chest radiographs for the diagnosis of acute respiratory distress syndrome
Am J Respir Crit Care Med
Agreement between alternative classifications of acute respiratory distress syndrome
Am J Respir Crit Care Med
Acute respiratory distress syndrome: the Berlin definition
JAMA
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Institution where work was performed: University Medical Center of El Paso, El Paso, Texas.