Diagnostic utility of C-reactive protein combined with brain natriuretic peptide in acute pulmonary edema: a cross sectional study

Bilateral Upper Lobe Pulmonary Oedema and Primary Mitral Regurgitation

Pulmonary oedema of uncertain aetiology is a diagnostic challenge to clinicians worldwide. Many indicators are proposed to differentiate between cardiogenic and non-cardiogenic pulmonary oedema. Mixed pulmonary oedema is an overlap between high hydrostatic pressure and increased permeability at the microvascular level. In our case, a 77-year-old patient presented with a nine-day history of shortness of breath. He was hypoxemic in the emergency department, had a pan-systolic murmur on auscultation, and blood results showed raised inflammatory markers without any fever. His chest X-ray and computed tomography pulmonary angiogram showed asymmetric pulmonary oedema in bilateral superior lobes and bilateral pleural effusions. Point-of-care echocardiography revealed severe mitral regurgitation. Trans-oesophageal echocardiography confirmed mitral valve prolapse with the chordae rupture and systolic vein reversal flow seen in the right superior pulmonary vein. He was treated with antibiotics and diuretics. After starting intravenous diuretics, there was a rapid symptomatic improvement, and a repeat chest X-ray showed significant improvements. We concluded that it was a case of mixed pulmonary oedema with predominant cardiac aetiology, and he was referred to cardiothoracic surgery for mitral valve replacement. The case showed that mixed pulmonary oedema with atypical chest radiography appearances would be a diagnostic challenge for clinicians. In such presentations, both cardiogenic and non-cariogenic causes of pulmonary oedema should be considered.

ARDS Clinical Practice Guideline 2021

Background

The joint committee of the Japanese Society of Intensive Care Medicine/Japanese Respiratory Society/Japanese Society of Respiratory Care Medicine on ARDS Clinical Practice Guideline has created and released the ARDS Clinical Practice Guideline 2021.

Methods

The 2016 edition of the Clinical Practice Guideline covered clinical questions (CQs) that targeted only adults, but the present guideline includes 15 CQs for children in addition to 46 CQs for adults. As with the previous edition, we used a systematic review method with the Grading of Recommendations Assessment Development and Evaluation (GRADE) system as well as a degree of recommendation determination method. We also conducted systematic reviews that used meta-analyses of diagnostic accuracy and network meta-analyses as a new method.

Results

Recommendations for adult patients with ARDS are described: we suggest against using serum C-reactive protein and procalcitonin levels to identify bacterial pneumonia as the underlying disease (GRADE 2D); we recommend limiting tidal volume to 4–8 mL/kg for mechanical ventilation (GRADE 1D); we recommend against managements targeting an excessively low SpO₂ (PaO₂) (GRADE 2D); we suggest against using transpulmonary pressure as a routine basis in positive end-expiratory pressure settings (GRADE 2B); we suggest implementing extracorporeal membrane oxygenation for those with severe ARDS (GRADE 2B); we suggest against using high-dose steroids (GRADE 2C); and we recommend using low-dose steroids (GRADE 1B). The recommendations for pediatric patients with ARDS are as follows: we suggest against using non-invasive respiratory support (non-invasive positive pressure ventilation/high-flow nasal cannula oxygen therapy) (GRADE 2D), we suggest placing pediatric patients with moderate ARDS in the prone position (GRADE 2D), we suggest against routinely implementing NO inhalation therapy (GRADE 2C), and we suggest against implementing daily sedation interruption for pediatric patients with respiratory failure (GRADE 2D).

Conclusions

This article is a translated summary of the full version of the ARDS Clinical Practice Guideline 2021 published in Japanese (URL: https://www.jsicm.org/publication/guideline.html). The original text, which was written for Japanese healthcare professionals, may include different perspectives from healthcare professionals of other countries.

Supplementary Information

The online version contains supplementary material available at 10.1186/s40560-022-00615-6.

ARDS clinical practice guideline 2021

BACKGROUND

The joint committee of the Japanese Society of Intensive Care Medicine/Japanese Respiratory Society/Japanese Society of Respiratory Care Medicine on ARDS Clinical Practice Guideline has created and released the ARDS Clinical Practice Guideline 2021.

METHODS

The 2016 edition of the Clinical Practice Guideline covered clinical questions (CQs) that targeted only adults, but the present guideline includes 15 CQs for children in addition to 46 CQs for adults. As with the previous edition, we used a systematic review method with the Grading of Recommendations Assessment Development and Evaluation (GRADE) system as well as a degree of recommendation determination method. We also conducted systematic reviews that used meta-analyses of diagnostic accuracy and network meta-analyses as a new method.

RESULTS

Recommendations for adult patients with ARDS are described: we suggest against using serum C-reactive protein and procalcitonin levels to identify bacterial pneumonia as the underlying disease (GRADE 2D); we recommend limiting tidal volume to 4-8 mL/kg for mechanical ventilation (GRADE 1D); we recommend against managements targeting an excessively low SpO₂ (PaO₂) (GRADE 2D); we suggest against using transpulmonary pressure as a routine basis in positive end-expiratory pressure settings (GRADE 2B); we suggest implementing extracorporeal membrane oxygenation for those with severe ARDS (GRADE 2B); we suggest against using high-dose steroids (GRADE 2C); and we recommend using low-dose steroids (GRADE 1B). The recommendations for pediatric patients with ARDS are as follows: we suggest against using non-invasive respiratory support (non-invasive positive pressure ventilation/high-flow nasal cannula oxygen therapy) (GRADE 2D); we suggest placing pediatric patients with moderate ARDS in the prone position (GRADE 2D); we suggest against routinely implementing NO inhalation therapy (GRADE 2C); and we suggest against implementing daily sedation interruption for pediatric patients with respiratory failure (GRADE 2D).

CONCLUSIONS

This article is a translated summary of the full version of the ARDS Clinical Practice Guideline 2021 published in Japanese (URL: https://www.jrs.or.jp/publication/jrs_guidelines/). The original text, which was written for Japanese healthcare professionals, may include different perspectives from healthcare professionals of other countries.

Protocol for a systematic review and meta-analysis of studies on the use of brain natriuretic peptide and N-terminal brain natriuretic peptide levels in the diagnosis of cardiopulmonary edema in acute respiratory failure

BACKGROUND

Dyspnea with bilateral pulmonary edema is common among patients in emergency departments (EDs) or intensive care units (ICUs). For the initial management of patients with this condition, cardiopulmonary edema (CPE) must be differentiated from acute respiratory distress syndrome (ARDS) in clinical settings. Brain natriuretic peptide (BNP) and N-terminal brain natriuretic peptide (NT-proBNP) are useful in distinguishing these conditions. However, current data about the use of these indexes are limited. Hence, we planned to perform a systematic review and meta-analysis to determine the accuracy of the two indexes for the diagnosis of CPE.

METHODS

We designed and registered a study protocol for a systematic review and meta-analysis. This study aims to determine the diagnostic accuracy of BNP and NT-proBNP based on the standards of the methodology of the Cochrane Handbook for Systematic Reviews of Diagnostic Test Accuracy and the Preferred Reporting Items for a Systematic Review and Meta-analysis of Diagnostic Test Accuracy Studies in reporting the findings of this review. We will search PubMed (MEDLINE), Cochrane Library, Embase, www.ClinicalTrials.gov , International Clinical Trials Registry Platform, and Google Scholar. Randomized controlled trials, cross-sectional studies, and observational cohort studies reporting the accuracy in diagnosing CPE among adult patients with dyspnea and bilateral pulmonary edema will be included in the analysis. There will be no limits regarding language and publication date for this review. Two reviewers will independently screen articles, extract data, evaluate for quality and bias using the Quality Assessment of Diagnostic Accuracy Studies (QUADAS-2), and use Grading of Recommendations Assessment, Development and Evaluation to summarize the strength of body of evidence. Then, a meta-analysis will be performed, and different statistical methods will be used to investigate heterogeneity among studies. A subgroup analysis of elderly patients with left ventricular dysfunction or chronic renal dysfunction will be performed. In the meta-analysis, a hierarchical summary receiver operating characteristic model or a bivariate model will be used in each index test, as appropriate.

DISCUSSION

A systematic review and meta-analysis of the accuracy of BNP and NT-proBNP for the diagnosis of CPE will be conducted. The result of this study can help clinicians to identify an appropriate initial treatment for patients with acute respiratory failure, including those with ARDS and CPE. To the best of our knowledge, this will be the first comprehensive systematic review focusing on ARDS management in a specific population.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO ID CRD42020201576.

Biomarker Value in the Diagnosis of Community-Acquired Pneumonia with Concomitant Chronic Heart Failure

The diagnosis of community-acquired pneumonia (CAP) with chronic heart failure (CHF) is associated with objective difficulties. Our case–control study aims to establish whether established serum inflammatory biomarkers are relevant to the diagnosis of CAP in patients with CHF. Seventy inpatients with previously diagnosed CHF and suspected non-severe CAP were recruited and then stratified into two subgroups with confirmed and rejected diagnosis of CAP. C-reactive protein (CRP), procalcitonin (PCT), tumor necrosis factor α (TNFα), interleukin-6 (IL-6) and brain natriuretic peptide (BNP) were measured. The value of biomarkers was determined using logistic regression, and their discriminatory efficacy was assessed by analyzing receiver operating characteristic (ROC) curves. Significantly higher levels of CRP 50.0 (35.5–98.5) mg/L, PCT 0.10 (0.05–0.54) ng/mL and IL-6 46.1(21.4–150.3) pg/mL in cases were identified as compared to the control group—15.0 (9.5–25.0) mg/L, 0.05 (0.05–0.05) ng/mL and 13.6 (9.5; 25.0) pg/mL, respectively. The Area Under the ROC Curve (95% CI) was the highest for CRP—0.91 (0.83–0.98), followed by PCT—0.81 (0.72–0.90) and IL-6—0.81 (0.71–0.91). A CRP value of >28.5 mg/L had an optimal sensitivity and specificity ratio (85.7/91.4%). In conclusion, the measurement of serum CRP, PCT and IL-6 levels can be useful for the diagnosis of CAP in patients with CHF. CRP showed optimal diagnostic utility in this population.

Inflammatory and Hypercoagulable Biomarkers and Clinical Outcomes in COVID-19 Patients

Systemic inflammation and hypercoagulopathy are known pathophysiological processes of coronavirus disease 2019 (COVID-19), particularly in patients with known cardiovascular disease or its risk factors (CVD). However, whether a cumulative assessment of these biomarkers at admission could contribute to the prediction of in-hospital outcomes remains unknown. The CLAVIS-COVID registry was a Japanese nationwide retrospective multicenter observational study, supported by the Japanese Circulation Society. Consecutive hospitalized patients with pre-existing CVD and COVID-19 were enrolled. Patients were stratified by the tertiles of CRP and D-dimer values at the time of admission. Multivariable Cox proportional hazard models were constructed. In 461 patients (65.5% male; median age, 70.0), the median baseline CRP and D-dimer was 58.3 (interquartile range, 18.2-116.0) mg/L and 1.5 (interquartile range, 0.8-3.0) mg/L, respectively. Overall, the in-hospital mortality rate was 16.5%, and the rates steadily increased in concordance with both CRP (5.0%, 15.0%, and 28.2%, respectively p < 0.001) and D-dimer values (6.8%, 19.6%, and 22.5%, respectively p = 0.001). Patients with the lowest tertiles of both biomarkers (CRP, 29.0 mg/L; D-dimer, 1.00 mg/L) were at extremely low risk of in-hospital mortality (0% until day 50, and 1.4% overall). Conversely, the elevation of both CRP and D-dimer levels was a significant predictor of in-hospital mortality (Hazard ratio, 2.97; 95% confidence interval, 1.57-5.60). A similar trend was observed when the biomarker threshold was set at a clinically relevant threshold. In conclusion, the combination of these abnormalities may provide a framework for rapid risk estimation for in-hospital COVID-19 patients with CVD.

Influenza infection, SARS, MERS and COVID-19: Cytokine storm - The common denominator and the lessons to be learned

The outbreak of COVID-19 reminds us that the emerging and reemerging respiratory virus infections pose a continuing threat to human life. Cytokine storm syndromes of viral origin seem to have a common pathogenesis of the imbalanced immune response with the exaggerated inflammatory reaction combined with the reduction and functional exhaustion of T cells. Immunomodulatory therapy is gaining interest in COVID-19, but this strategy has received less attention in other respiratory viral infections than it deserved. In this review we suggest that based on the similarities of the immune dysfunction in the severe cases of different respiratory viral infections, some lessons from the immunomodulatory therapy of COVID-19 (particularly regarding the choice of an immunomodulatory drug, the selection of patients and optimal time window for this kind of therapy) could be applied for some cases of severe influenza infection and probably for some future outbreaks of novel severe respiratory viral infections.

Systemic Markers of Monocyte Activation in Acute Pulmonary Oedema

BACKGROUND

Hydrostatic lung injury followed by pulmonary remodelling variably complicates cardiogenic acute pulmonary oedema (APO). Pulmonary remodelling may be regulated by the balance between distinct phenotypes of pulmonary macrophages; activated/inflammatory (M1), and reparative/anti-inflammatory (M2), derived from circulating monocyte populations. The aim of this study was to identify biomarkers in peripheral blood that are consistent with hydrostatic lung injury and pulmonary remodelling in APO and which follow the variable clinical course.

METHODS

To examine peripheral markers of lung inflammation, resolution and remodelling, 18 patients, admitted to the intensive care unit (ICU) with a clinical diagnosis of APO, were enrolled. Admission, 12- and 24-hour post-admission bloods were assayed for cytokines by ELISA (R&D Systems, Minneapolis, MN, USA) and leukocyte surface markers by flow cytometry.

RESULTS

Admission PaO₂ to FiO₂ ratio was positively correlated with Mon 2 (intermediate) monocyte prevalence, through increasing ratio of CD16⁺ monocytes to CD11b⁺ and CD40⁺ monocytes, and negatively correlated with Mon 1 (classical) monocyte prevalence, through decreasing ratio of CD16⁺ monocytes to CD62L⁺. Secondary cohort analysis compared 10 APO patients with established chronic heart failure (CHF) to eight without CHF. An increase in monocyte chemotactic peptide (MCP)-1, monocyte prevalence, and CD16^-CD62L⁺ monocytes with CHF, all characteristic of monocyte activation to a Mon 1 phenotype, were found in the CHF APO patients.

CONCLUSIONS

Increased systemic monocyte prevalence and expression of cell surface markers suggest a Mon 1 profile in CHF patients during episodes of APO. Future studies should define the role of systemic monocyte prevalence and activation in decompensated CHF.

A systematic review of biomarkers multivariately associated with acute respiratory distress syndrome development and mortality

Background

Heterogeneity of acute respiratory distress syndrome (ARDS) could be reduced by identification of biomarker-based phenotypes. The set of ARDS biomarkers to prospectively define these phenotypes remains to be established.

Objective

To provide an overview of the biomarkers that were multivariately associated with ARDS development or mortality.

Data sources

We performed a systematic search in Embase, MEDLINE, Web of Science, Cochrane CENTRAL, and Google Scholar from inception until 6 March 2020.

Study selection

Studies assessing biomarkers for ARDS development in critically ill patients at risk for ARDS and mortality due to ARDS adjusted in multivariate analyses were included.

Data extraction and synthesis

We included 35 studies for ARDS development (10,667 patients at risk for ARDS) and 53 for ARDS mortality (15,344 patients with ARDS). These studies were too heterogeneous to be used in a meta-analysis, as time until outcome and the variables used in the multivariate analyses varied widely between studies. After qualitative inspection, high plasma levels of angiopoeitin-2 and receptor for advanced glycation end products (RAGE) were associated with an increased risk of ARDS development. None of the biomarkers (plasma angiopoeitin-2, C-reactive protein, interleukin-8, RAGE, surfactant protein D, and Von Willebrand factor) was clearly associated with mortality.

Conclusions

Biomarker data reporting and variables used in multivariate analyses differed greatly between studies. Angiopoeitin-2 and RAGE in plasma were positively associated with increased risk of ARDS development. None of the biomarkers independently predicted mortality. Therefore, we suggested to structurally investigate a combination of biomarkers and clinical parameters in order to find more homogeneous ARDS phenotypes.

PROSPERO identifier

PROSPERO, CRD42017078957

Lung injury prediction scores: Clinical validation and C-reactive protein involvement in high risk patients

OBJECTIVE

A study was made to validate two previously derived lung injury prediction scores (LIPS) for the prediction of acute respiratory distress syndrome (ARDS) in high risk intensive care patients, with the incorporation of C-reactive protein (CRP) for improving score accuracy.

DESIGN

A prospective, observational cohort study was carried out.

PATIENTS

A total of 200 patients with APACHE II score ≥15 and at least one ARDS risk factor upon ICU admission were included.

INTERVENTIONS

Calculation of LIPS using formulas developed by Cartin-Ceba et al. (2009) and Trillo-Alvarez et al. (2011) (LIPS-2009 and LIPS-2011). C-reactive protein was measured upon admission (CRP-0) and after 48h (CRP-48).

MAIN VARIABLES OF INTEREST

Independent variables: LIPS-2009, LIPS-2011 and CRP values. Dependent variable: development of ARDS.

RESULTS

Eighty-eight patients (44%) developed ARDS after a median (Q₁-Q₃) of 2.5 (1.3-6.8) days. The LIPS-2009 and LIPS-2011 scores were 4 (3-6) and 5 (3.6-6.5) in ARDS patients compared to 2 (1-4) and 3.5 (1.5-4.5) in non-ARDS patients (p<0.001). CRP-48 was 96 (67.5-150.3)mg/L and 48 (24-96)mg/L in the two groups, respectively (p<0.001). ΔCRP (i.e., CRP-48 minus CRP-0) was significantly higher in the ARDS patients (p<0.001). The AUC was 0.740 and 0.738 for LIPS-2011 and LIPS-2009, respectively - the difference being nonsignificant (p=0.9, 0.9 and 0.8 for pairwise comparison of the different ROC curves). Integrating ΔCRP with LIPS-2011 using binary logistic regression analysis identified a new score (LIPS-N) with AUC 0.803, which was significantly higher than the AUC of LIPS-2011 (p=0.01).

CONCLUSIONS

Both LIPS scores are equally effective in predicting ARDS in high risk ICU patients. Integrating the change in CRP within the score might improve its accuracy.

A systematic review of diagnostic methods to differentiate acute lung injury/acute respiratory distress syndrome from cardiogenic pulmonary edema

BACKGROUND

Discriminating acute lung injury (ALI) or acute respiratory distress syndrome (ARDS) from cardiogenic pulmonary edema (CPE) is often challenging. This systematic review examines studies using biomarkers or images to distinguish ALI/ARDS from CPE.

METHODS

Three investigators independently identified studies designed to distinguish ALI/ARDS from CPE in adults. Studies were identified from PubMed, and the Cochrane Central Register of Controlled Trials database until July 3, 2017.

RESULTS

Of 475 titles and abstracts screened, 38 full texts were selected for review, and we finally included 24 studies in this systematic review: 21 prospective observational studies, two retrospective observational studies, and one retrospective combined with prospective study. These studies compared various biomarkers to differentiate subjects with ALI/ARDS and in those with CPE, and 13 calculated the area under the receiver operator characteristic curve (AUC). The most commonly studied biomarker (four studies) was brain natriuretic peptide (BNP) and the discriminatory ability ranged from AUC 0.67-0.87 but the timing of measurement varied. Other potential biomarkers or tools have been reported, but only as single studies.

CONCLUSIONS

There were no identified biomarkers or tools with high-quality evidence for differentiating ALI/ARDS from CPE. Combining clinical criteria with validated biomarkers may improve the predictive accuracy.

Transpulmonary Thermodilution-Based Management of Neurogenic Pulmonary Edema After Subarachnoid Hemorrhage

Neurogenic pulmonary edema (NPE) is a potentially catastrophic but treatable systemic event after subarachnoid hemorrhage (SAH). The development of NPE most frequently occurs immediately after SAH, and the severity is usually self-limiting. Despite extensive research efforts and a breadth of collective clinical experience, accurate diagnosis of NPE can be difficult, and effective hemodynamic treatment options are limited. Recently, a bedside transpulmonary thermodilution device has been introduced that traces physiological patterns consistent with current theories regarding the mechanism (hydrostatic or permeability PE) of NPE. This article provides an overview of the clinical usefulness of the advanced technique for use in the neurointensive care unit for the diagnosis and management of post-SAH NPE.

Comparison of hospital mortality and long-term survival in patients with acute lung injury/ARDS vs cardiogenic pulmonary edema

BACKGROUND

Early differential diagnosis of acute lung injury (ALI) vs cardiogenic pulmonary edema (CPE) is important for selecting the most appropriate therapy, but the prognostic implications of this distinction have not been studied. Accurate prognostic information is essential for providing appropriate informed consent prior to initiation of mechanical ventilation.

METHODS

This is a long-term follow-up study of a previously established population-based cohort of critically ill adult patients with acute pulmonary edema admitted at a tertiary-care center during 2006 to 2009, in which post hoc expert review had established ALI vs CPE diagnosis. Using logistic and Cox regression, hospital mortality and long-term survival were compared in patients with ALI vs patients with CPE.

RESULTS

Of 328 patients (ALI = 155, CPE = 173), 240 patients (73%) died during a median follow-up of 160 days. After adjusting for confounders, patients with ALI were significantly more likely to die in the hospital (OR = 4.2, 95% CI = 2.3-7.8, n = 325, P < .001), but among hospital survivors the risk of death during follow-up was the same in both groups (hazard ratio = 1.13, 95% CI = 0.79-1.62, n = 229, P = .50). Independent predictors of mortality included age and APACHE (Acute Physiology and Chronic Health Evaluation) III score. Results were similar when restricting patients with ALI to the subset with ARDS (Berlin definition). In post hoc analyses, the mortality rate in hospital survivors compared with the general US population was significantly higher during the first 2 years but essentially converged by year five.

CONCLUSIONS

Although hospital mortality is higher in patients with ALI/ARDS compared with patients with CPE, long-term survival is similar in hospital survivors from both groups.

Albumin rather than C-reactive protein may be valuable in predicting and monitoring the severity and course of acute respiratory distress syndrome in critically ill patients with or at risk for the syndrome after new onset fever

BACKGROUND

We studied the value of routine biochemical variables albumin, C-reactive protein (CRP) and lactate dehydrogenase (LDH) to improve prediction and monitoring of acute respiratory distress syndrome (ARDS) severity in the intensive care unit.

METHODS

In 101 critically ill patients, with or at risk for ARDS after new onset fever, data were collected on days (D) 0, 1, 2, and 7 after inclusion. ARDS was defined by the Berlin definition and lung injury score (LIS).

RESULTS

At baseline, 48 patients had mild to severe ARDS according to Berlin and 87 according to LIS (Rs = 0.54, P < 0.001). Low baseline albumin levels were moderately associated with maximum Berlin and LIS categories within 7 days; an elevated CRP level was moderately associated with maximum Berlin categories only. The day-by-day Berlin and LIS categories were inversely associated with albumin levels (P = 0.01, P < 0.001) and directly with CRP levels (P = 0.02, P = 0.04, respectively). Low albumin levels had monitoring value for ARDS severity on all study days (area under the receiver operating characteristic curve, AUROC, 0.62-0.82, P < 0.001-0.03), whereas supranormal CRP levels performed less . When the Berlin or LIS category increased, albumin levels decreased ≥1 g/L (AUROC 0.72-0.77, P = 0.001) and CRP increased ≥104 mg/L (only significant for Berlin, AUROC 0.69, P = 0.04). When the LIS decreased, albumin levels increased ≥1 g/L (AUROC 0.68, P = 0.02). LDH was higher in 28-day non-survivors than survivors (P = 0.007).

CONCLUSIONS

Overall, albumin may be of greater value than CRP in predicting and monitoring the severity and course of ARDS in critically patients with or at risk for the syndrome after new onset fever. Albumin levels below 20 g/L as well as a decline over a week are associated with ARDS of increasing severity, irrespective of its definition. LDH levels predicted 28-day mortality.

Decision support tool for differential diagnosis of Acute Respiratory Distress Syndrome (ARDS) vs Cardiogenic Pulmonary Edema (CPE): a prospective validation and meta-analysis

Introduction

We recently presented a prediction score providing decision support with the often-challenging early differential diagnosis of acute lung injury (ALI) vs cardiogenic pulmonary edema (CPE). To facilitate clinical adoption, our objective was to prospectively validate its performance in an independent cohort.

Methods

Over 9 months, adult patients consecutively admitted to any intensive care unit of a tertiary-care center developing acute pulmonary edema were identified in real-time using validated electronic surveillance. For eligible patients, predictors were abstracted from medical records within 48 hours of the alert. Post-hoc expert review blinded to the prediction score established gold standard diagnosis.

Results

Of 1,516 patients identified by electronic surveillance, data were abstracted for 249 patients (93% within 48 hours of disease onset), of which expert review (kappa 0.93) classified 72 as ALI, 73 as CPE and excluded 104 as “other”. With an area under the curve (AUC) of 0.81 (95% confidence interval =0.73 to 0.88) the prediction score showed similar discrimination as in prior cohorts (development AUC = 0.81, P = 0.91; retrospective validation AUC = 0.80, P = 0.92). Hosmer-Lemeshow test was significant (P = 0.01), but across eight previously defined score ranges probabilities of ALI vs CPE were the same as in the development cohort (P = 0.60). Results were the same when comparing acute respiratory distress syndrome (ARDS, Berlin definition) vs CPE.

Conclusion

The clinical prediction score reliably differentiates ARDS/ALI vs CPE. Pooled results provide precise estimates of the score’s performance which can be used to screen patient populations or to assess the probability of ALI/ARDS vs CPE in specific patients. The score may thus facilitate early inclusion into research studies and expedite prompt treatment.

Electronic supplementary material

The online version of this article (doi:10.1186/s13054-014-0659-x) contains supplementary material, which is available to authorized users.

Computed tomography findings of aspiration pneumonia in 53 patients

AIM

No large case series has so far shown the chest computed tomography (CT) features in patients with aspiration pneumonia, despite the fact that aspiration pneumonia is the most common pulmonary disease in the elderly and is regarded as gravity-dependent pneumonia. The aim of the present study was to elucidate the CT features based on the patients' status in patients with dysphagia-associated aspiration pneumonia.

METHODS

A total of 53 patients, who were hospitalized because of pneumonia and subsequently confirmed to have dysphagia by videofluorography, were entered into this study. The CT findings were independently evaluated by two radiologists who were unaware of the patients' clinical information. The relationships between the patients' status and the CT patterns of pneumonia or their distributions were analyzed.

RESULTS

There were eight patients (15%) with lobar pneumonia, 36 patients (68%) with bronchopneumonia and nine patients (17%) with bronchiolitis. Posterior lung predominance was seen in 49 patients (92%). In the craniocaudal observation, lower lung predominance was found in 25 patients (47%) and diffuse distribution was seen in 28 patients (53%). A decreased performance status was significantly associated with a diffuse distribution (P=0.039).

CONCLUSIONS

Aspiration pneumonia more frequently presented as a bronchopneumonia pattern followed by a bronchiolitis pattern on CT. Their distributions were characterized by gravity dependence, and anterior- or upper lung-limited pneumonia might not be due to dysphagia-associated pneumonia.

Relationship between CT findings and the plasma levels of brain natriuretic peptide in 29 patients with acute cardiogenic pulmonary edema

RATIONALE AND OBJECTIVES

Brain natriuretic peptide (BNP) is a useful biomarker for the assessment of cardiogenic pulmonary edema. This study evaluated the relationship between computed tomography (CT) findings and plasma BNP levels in patients with cardiogenic pulmonary edema.

MATERIALS AND METHODS

Twenty-nine consecutive outpatients with severe respiratory failure from cardiogenic edema presenting to emergency departments were enrolled. They underwent chest CT and plasma BNP levels were measured in the emergency room. CT findings were independently evaluated by two radiologists who were unaware of the patients' clinical information.

RESULTS

The plasma BNP levels only correlated with the volume of pleural effusion in each side (right: r(s) = 0.519, P = .004; left: r(s) = 0.460, P = .012). No significant correlation was observed between the BNP levels and the findings of lung parenchyma or cardiovascular enlargement.

CONCLUSION

Estimating the pleural effusion volume with CT may be a feasible method as well as measuring the plasma BNP level in the assessment of acute cardiogenic pulmonary edema.