Brain natriuretic peptide in the evaluation of emergency department dyspnea: is there a role?

Biomarkers as Prognostic Predictors and Therapeutic Guide in Critically Ill Patients: Clinical Evidence

A biomarker is a molecule that can be measured in a biological sample in an objective, systematic, and precise way, whose levels indicate whether a process is normal or pathological. Knowing the most important biomarkers and their characteristics is the key to precision medicine in intensive and perioperative care. Biomarkers can be used to diagnose, in assessment of disease severity, to stratify risk, to predict and guide clinical decisions, and to guide treatments and response to them. In this review, we will analyze what characteristics a biomarker should have and how to ensure its usefulness, and we will review the biomarkers that in our opinion can make their knowledge more useful to the reader in their clinical practice, with a future perspective. These biomarkers, in our opinion, are lactate, C-Reactive Protein, Troponins T and I, Brain Natriuretic Peptides, Procalcitonin, MR-ProAdrenomedullin and BioAdrenomedullin, Neutrophil/lymphocyte ratio and lymphopenia, Proenkephalin, NefroCheck, Neutrophil gelatinase-associated lipocalin (NGAL), Interleukin 6, Urokinase-type soluble plasminogen activator receptor (suPAR), Presepsin, Pancreatic Stone Protein (PSP), and Dipeptidyl peptidase 3 (DPP3). Finally, we propose an approach to the perioperative evaluation of high-risk patients and critically ill patients in the Intensive Care Unit (ICU) based on biomarkers.

Delirium Prevention, Detection, and Treatment in Emergency Medicine Settings: A Geriatric Emergency Care Applied Research (GEAR) Network Scoping Review and Consensus Statement

BACKGROUND

Older adult delirium is often unrecognized in the emergency department (ED), yet the most compelling research questions to overcome knowledge-to-practice deficits remain undefined. The Geriatric Emergency care Applied Research (GEAR) Network was organized to identify and prioritize delirium clinical questions.

METHODS

GEAR identified and engaged 49 transdisciplinary stakeholders including emergency physicians, geriatricians, nurses, social workers, pharmacists, and patient advocates. Adhering to Preferred Reporting Items for Systematic Reviews and Meta-Analyses for Scoping Reviews, clinical questions were derived, medical librarian electronic searches were conducted, and applicable research evidence was synthesized for ED delirium detection, prevention, and management. The scoping review served as the foundation for a consensus conference to identify the highest priority research foci.

RESULTS

In the scoping review, 27 delirium detection "instruments" were described in 48 ED studies and used variable criterion standards with the result of delirium prevalence ranging from 6% to 38%. Clinician gestalt was the most common "instrument" evaluated with sensitivity ranging from 0% to 81% and specificity from 65% to 100%. For delirium management, 15 relevant studies were identified, including one randomized controlled trial. Some intervention studies targeted clinicians via education and others used clinical pathways. Three medications were evaluated to reduce or prevent ED delirium. No intervention consistently prevented or treated delirium. After reviewing the scoping review results, the GEAR stakeholders identified ED delirium prevention interventions not reliant on additional nurse or physician effort as the highest priority research.

CONCLUSIONS

Transdisciplinary stakeholders prioritize ED delirium prevention studies that are not reliant on health care worker tasks instead of alternative research directions such as defining etiologic delirium phenotypes to target prevention or intervention strategies.

Diagnostic Utility of N-terminal pro-Brain Natriuretic Peptide and C-reactive Protein in Diagnosing Heart Failure in Patients with Acute Hypoxemic Respiratory Failure

Introduction Shortness of breath is a leading cause of intensive care unit (ICU) admissions and is multifactorial. Acute hypoxemic respiratory failure due to heart failure is one of the leading causes of ICU admissions. N-terminal pro-brain natriuretic peptide (NT-proBNP) is secreted by ventricles and carries a negative predictive value for heart failure (2). NT-proBNP can also be raised in sepsis (4). Changes in NT-proBNP strongly correlated with changes in C-reactive protein (CRP) and leukocytes levels (8). Objective This study was conducted to explore the diagnostic utility of NT-proBNP and CRP to diagnose heart failure in patients presenting with acute hypoxemic respiratory failure. Materials and methods After informed consent and approval from the institutional review board (IRB), patients of acute hypoxemic respiratory failure were included in the study. History and physical examination were done by a medical resident and recorded in the patients' files. Data were transferred to a structured proforma by the researcher. All tests were conducted within three hours of presentation. The diagnosis of heart failure was made by a panel of experts, including the consultant cardiologist and consultant intensivist in charge. The chest X-ray was reported by the radiologist. The cost of the test was afforded by the institution. Data were analyzed by SPSS version 15 (SPSS Inc., Chicago, Illinois). Analysis of variance (ANOVA), Pearson correlation and linear regression were applied to find out the relation between variables and significance. Results We studied 137 patients. Out of them, 72.9% were diagnosed as heart failure. Heart failure was more common in females (43.7%) as compared to males (29%). NT-proBNP was raised in 111 (81%) patients and out of them, 88 patients (79%) had heart failure. Sensitivity and specificity of NT-proBNP were found to be (95.56%) and (46.81%), respectively. Similarly, CRP was 90% sensitive and 25.53% specific for heart failure. The most common findings in chest X-rays of patients with heart failure were upper lobe diversion and enlarged cardiothoracic ratio (71%). Conclusion We concluded our study as NT-proBNP is a highly sensitive test to diagnose heart failure in settings of acute hypoxemic respiratory failure. CRP is also significantly raised in heart failure. Upper lobe diversion and an increased cardiothoracic ratio is a strong predictor of heart failure.

Early identification of acute heart failure at the time of presentation: do natriuretic peptides make the difference?

Background

The early identification of patients with acute heart failure (AHF) is challenging as many other diseases lead to a clinical presentation with dyspnea.

Aim

The aim of the study was to evaluate the impact of natriuretic peptides at common HF study cut‐offs on the diagnosis of patients with dyspnea at admission.

Methods and results

For this post hoc analysis, we analysed n = 726 European Union (EU) patients from the prospective BACH (Biomarkers in Acute Heart Failure) study. Cut‐offs were 350 ng/L (BNP), 300 pmol/L [pro‐atrial natriuretic peptide (proANP)], and 1800 ng/L (NT‐proBNP). These cut‐offs had equivalent 90 days' mortality in the EU cohort of BACH. We analysed the effect of selection using these cut‐offs on the prevalence of the gold standard diagnoses made in the BACH study and the respective mortality. The prevalence of AHF is increased from 47.5 to 75.6% (NT‐proBNP criteria) up to 79.7% (BNP criteria). With the use of the proANP criteria, 90 days' mortality of patients with AHF rose from 14 to 17% (P = 0.029). In the group with no‐AHF diagnoses, mortality rose from 10 to 25% (P < 0.001).

Conclusions

The prevalence of patients with the gold standard diagnoses of AHF among those presenting with dyspnea to the emergency department is significantly increased by the use of natriuretic peptides with common cut‐offs used in prospective HF studies. Nevertheless, in the selected groups, patients with no AHF diagnosis have the highest mortality, and therefore, the addition of a natriuretic peptide alone is insufficient to start specific therapies.

Approach to undifferentiated dyspnea in emergency department: aids in rapid clinical decision-making

Background

Diagnosis and management of patients presenting with acute dyspnea is one of the major challenges for physicians in emergency department (ED). A correct diagnosis is frequently delayed and difficult to ascertain, and clinical uncertainty is common, explaining the need for rapid diagnosis and a management plan. The primary aim of our study is to assess a diagnostic strategy using multiorgan point of care ultrasonography (USG) to differentiate patients presenting with acute dyspnea to ED into different diagnostic categories for timely management in a resource-limited setting.

Methods

This is a prospective cohort study which assessed the diagnostic performance of a strategy in evaluating patients presenting with undifferentiated dyspnea as primary predominant complaint to ED. Focused multiorgan USG which includes cardiac USG for left ventricle systolic function, right ventricle enlargement, and pericardial effusion, inferior vena cava (IVC) diameter and collapsibility, lung USG to identify various patterns (acute interstitial syndrome, pneumothorax, pleural effusion, consolidation, etc.) and renal USG to assess kidney size and echotexture was performed. Later, patients were grouped into one of ten clinical syndromes defined in the study based on USG and clinical patterns. Emergency diagnosis was compared with final hospital diagnosis to assess the accuracy of this strategy.

Results

Concordance between ED diagnosis of dyspnea using the diagnostic strategy proposed in the study with final hospital diagnosis was high with agreement in 88% of patients (Kappa statistic = .805, p = .000) which is statistically significant. The most common diagnosis was acute decompensated heart failure (ADHF). Sensitivity and specificity of the diagnostic strategy used in this study to identify ADHF was 97.3 and 93.3%, respectively. On multivariate analysis, jugular venous distension, fever and cough, ejection fraction (by eyeball method), dilated IVC, absent to decreased lung sliding showed independent association in predicting cardiac and non-cardiac diagnosis.

Conclusions

The present study concludes that integrating focused multiorgan USG by lung-cardiac-IVC and renal ultrasound into routine clinical evaluation of patients with dyspnea has a higher accuracy for differentiating causes of dyspnea in emergency department. This strategy can be adopted even in resource limited setting.

Examining 30-day COPD readmissions through the emergency department

Background

Thirty-day readmission in COPD is common and costly, but potentially preventable. The emergency department (ED) may be a setting for COPD readmission reduction efforts.

Objective

To better understand COPD readmission through the ED, ascertain factors associated with 30-day readmission through the ED, and identify subgroups of patients with COPD for readmission reduction interventions.

Patients and methods

A retrospective cohort study was conducted from January 2009 to September 2015 in patients with COPD of age ≥18 years. Electronic health record data were abstracted for information available to admitting providers in the ED. The primary outcome was readmission through the ED within 30 days of discharge from an index admission for COPD. Logistic regression was used to examine the relationship between potential risk factors and 30-day readmission.

Results

The study involved 1,574 patients who presented to the ED within 30 days on an index admission for COPD. Of these, 82.2% were readmitted through the ED. Charlson score (odds ratio [OR]: 3.6; 95% CI: 2.9–4.4), a chief complaint of breathing difficulty (OR: 1.6; 95% CI: 1.1–2.6), outpatient utilization of albuterol (OR: 4.1; 95% CI: 2.6–6.4), fluticasone/salmeterol (OR: 2.3; 95% CI: 1.3–4.2), inhaled steroids (OR: 3.8; 95% CI: 1.3–10.7), and tiotropium (OR: 1.8; 95% CI: 1.0–3.2), as well as arterial blood gas (OR: 4.4; 95% CI: 1.3–15.1) and B-type natriuretic peptide (OR: 2.2; 95% CI: 1.4–3.5) testing in the ED were associated with readmission (c-statistic =0.936). Seventeen-point-eight percent of patients with COPD presented to the ED and were discharged home; 56% presented with a complaint other than breathing difficulty; and 16% of those readmitted for breathing difficulty had a length of stay <48 hours.

Conclusion

Intensive outpatient monitoring, evaluation, and follow-up after discharge are needed to help prevent re-presentation to the ED, as practically all patients with COPD who represent to the ED within 30 days are readmitted to the hospital and for a variety of clinical complaints. Among those patients with COPD who present with breathing difficulty, improved decision support algorithms and alternative management strategies are needed to identify and intervene on the subgroup of patients who require <48-hour length of stay.

Which method is best for an early accurate diagnosis of acute heart failure? Comparison between lung ultrasound, chest X-ray and NT pro-BNP performance: a prospective study

Acute heart failure is a common condition among adults presenting with dyspnea in the Emergency Department (ED), still the diagnosis is challenging as objective standardized criteria are lacking. First line work-up, other then clinical findings, is nowadays made with lung ultrasound imaging study, chest X-ray study and brain natriuretic peptide (BNP) level determination; however, it is not clear which is the best diagnostic test to be used and whether there is any real benefit for clinical judgement. We set up this study to compare the performances of these three diagnostic tools; furthermore, we combined them to find the best possible approach to dyspneic patients. This is a prospective observational study based in the ED. We enrolled adults presenting with dyspnea not trauma-related, they underwent lung ultrasound, and chest X-ray studies, and NT pro-BNP level determination. Then we compared the results with the diagnosis of acute heart failure established by an independent panel of experts. 236 patients were enrolled in the study. We find sensitivity and specificity for lung ultrasound of 57.73 and 87.97 %, for chest X-ray 74.49 and 86.26 %, for NT pro-BNP 97.59 and 27.56 %, respectively. Combining together the chest X-ray and lung ultrasound, we find the best overall performance with 84.69 % sensitivity, 77.69 % specificity and 87.07 % negative predictive value. From our results, we could not identify the "best test" to diagnose acute heart failure in an emergency setting, although we could suggest that a stepwise workup combining chest X-ray and lung ultrasound at first, then for those negative, a determination of NT pro-BNP assay would be a reasonable approach to the dyspneic patient.

Urinary cadmium levels predict mortality of patients with acute heart failure

BACKGROUND

Acute heart failure (AHF) is a serious condition that is associated with increased mortality in critically ill patients. Previous studies indicated that environmental exposure to cadmium increases mortality of general populations. However, the relationship of cadmium exposure and mortality is unclear for AHF patients.

MATERIALS AND METHODS

A total of 153 patients with AHF in intensive care units (ICUs) met the inclusion criteria and were followed up for 6 months. Demographic data, AHF etiology, hematological and biochemical data, and hospital mortality were recorded. The scores of two predictive systems (Sequential Organ Failure Assessment [SOFA], Acute Physiology and Chronic Health Evaluation II [APACHE II]) for mortality in critically ill patients were calculated, and urinary cadmium levels were recorded.

RESULTS

At the end of the follow-up period, the mortality rate was 24.8%. The survivors (n=115) had higher urinary cadmium levels on day 1 (D1UCd) of ICU admission than non-survivors (n=38). A multiple linear regression analysis revealed a positive correlation between D1UCd and acute kidney injury, but a negative correlation between D1UCd and the level of serum albumin. A multivariate Cox analysis indicated that D1UCd was an independent predictor of mortality in AHF patients. For each increment of 1 μg of D1UCd, the hazard ratio for ICU mortality was 1.20 (95% confidence interval [CI]: 1.09-1.32, P<0.001). The area under the receiver operating characteristic curve for D1UCd was 0.84 (95% CI: 0.78-0.91), better than the values for the SOFA and APACHE II systems.

CONCLUSION

The D1UCd may serve as a single predictor of hospital mortality for AHF patients in the ICU. Because of the high mortality and smaller sample size, more investigations are required to confirm these observations and elucidate the underlying mechanisms.

Point-of-care diagnostics for niche applications

Point-of-care or point-of-use diagnostics are analytical devices that provide clinically relevant information without the need for a core clinical laboratory. In this review we define point-of-care diagnostics as portable versions of assays performed in a traditional clinical chemistry laboratory. This review discusses five areas relevant to human and animal health where increased attention could produce significant impact: veterinary medicine, space travel, sports medicine, emergency medicine, and operating room efficiency. For each of these areas, clinical need, available commercial products, and ongoing research into new devices are highlighted.

Approach to Adult Patients with Acute Dyspnea

Undifferentiated patients in respiratory distress require immediate attention in the emergency department. Using a thorough history and clinical examination, clinicians can determine the most likely causes of dyspnea. Understanding the pathophysiology of the most common diseases contributing to dyspnea guides rational testing and informed, expedited treatment decisions.

Diagnosing Acute Heart Failure in the Emergency Department: A Systematic Review and Meta-analysis

BACKGROUND

Acute heart failure (AHF) is one of the most common diagnoses assigned to emergency department (ED) patients who are hospitalized. Despite its high prevalence in the emergency setting, the diagnosis of AHF in ED patients with undifferentiated dyspnea can be challenging.

OBJECTIVES

The primary objective of this study was to perform a systematic review and meta-analysis of the operating characteristics of diagnostic elements available to the emergency physician for diagnosing AHF. Secondary objectives were to develop a test-treatment threshold model and to calculate interval likelihood ratios (LRs) for natriuretic peptides (NPs) by pooling patient-level results.

METHODS

PubMed, EMBASE, and selected bibliographies were searched from January 1965 to March 2015 using MeSH terms to address the ability of the following index tests to predict AHF as a cause of dyspnea in adult patients in the ED: history and physical examination, electrocardiogram, chest radiograph (CXR), B-type natriuretic peptide (BNP), N-terminal proB-type natriuretic peptide (NT-proBNP), lung ultrasound (US), bedside echocardiography, and bioimpedance. A diagnosis of AHF based on clinical data combined with objective test results served as the criterion standard diagnosis. Data were analyzed using Meta-DiSc software. Authors of all NP studies were contacted to obtain patient-level data. The Quality Assessment Tool for Diagnostic Accuracy Studies-2 (QUADAS-2) for systematic reviews was utilized to evaluate the quality and applicability of the studies included.

RESULTS

Based on the included studies, the prevalence of AHF ranged from 29% to 79%. Index tests with pooled positive LRs ≥ 4 were the auscultation of S3 on physical examination (4.0, 95% confidence interval [CI] = 2.7 to 5.9), pulmonary edema on both CXR (4.8, 95% CI = 3.6 to 6.4) and lung US (7.4, 95% CI = 4.2 to 12.8), and reduced ejection fraction observed on bedside echocardiogram (4.1, 95% CI = 2.4 to 7.2). Tests with low negative LRs were BNP < 100 pg/mL (0.11, 95% CI = 0.07 to 0.16), NT-proBNP < 300 pg/mL (0.09, 95% CI = 0.03 to 0.34), and B-line pattern on lung US LR (0.16, 95% CI = 0.05 to 0.51). Interval LRs of BNP concentrations at the low end of "positive" results as defined by a cutoff of 100 pg/mL were substantially lower (100 to 200 pg/mL; 0.29, 95% CI = 0.23 to 0.38) than those associated with higher BNP concentrations (1000 to 1500 pg/mL; 7.12, 95% CI = 4.53 to 11.18). The interval LR of NT-proBNP concentrations even at very high values (30,000 to 200,000 pg/mL) was 3.30 (95% CI = 2.05 to 5.31).

CONCLUSIONS

Bedside lung US and echocardiography appear to the most useful tests for affirming the presence of AHF while NPs are valuable in excluding the diagnosis.

Overtesting and the Downstream Consequences of Overtreatment: Implications of "Preventing Overdiagnosis" for Emergency Medicine

Overtesting, the downstream consequences of overdiagnosis, and overtreatment of some patients are topics of growing debate within emergency medicine (EM). The "Preventing Overdiagnosis" conference, hosted by The Dartmouth Institute for Health Policy and Clinical Practice, with sponsorship from consumer organizations, medical journals, and academic institutions, is evidence of an expanding interest in this topic. However, EM represents a compellingly unique environment, with increased decision density tied to high stakes for patients and providers with missed or delayed diagnoses in a professional atmosphere that does not tolerate mistakes. This article reviews the relevance of this reductionist paradigm to EM, provides a first-hand synopsis of the first "Preventing Overdiagnosis" conference, and assesses barriers to moving the concept of less test ordering to reality.

Determination of a predictive cutoff value of NT-proBNP testing for long-term survival in ED patients with acute heart failure

OBJECTIVE

The main objective of this study was to determine a predictive cutoff value for plasma N-terminal pro-B-type natriuretic peptide (NT-proBNP) that could successfully predict the long-term (4-year) survival of patients with acute heart failure (HF) at the time of admission to the emergency department (ED). To our best knowledge, our study is the first research done to identify a predictive cutoff value for admission NT-proBNP to the prescriptive 4-year survival of patients admitted to ED with acute HF diagnosis.

METHODS

NT-proBNP levels were measured in plasma obtained from 99 patients with dyspnea and left ventricular dysfunction upon admission to the ED. The end point was survival from the time of inclusion through 4 years.

RESULTS

The mean age of the patients in this study was 71.1 ± 10.3 years; 50 of these patients were female. During the 4-year follow-up period, 76 patients died; survivors were significantly younger than non-survivors (64.26 ± 11.42 years vs 72.83 ± 11.07 years, P = .002). The optimal NT-proBNP cutoff point for predicting 4-year survival at the time of admission was 2300 pg/mL, which had 85.9% sensitivity and 39.1% specificity (95% confidence interval, area under the curve: 0.639, P = .044).

CONCLUSION

Elevated NT-proBNP levels at the time of admission are a strong and independent predictor of all-cause mortality in patients with acute HF 4 years after admission. Furthermore, the optimal cutoff level of NT-proBNP used to predict 4-year survival had high sensitivity. However, especially in the case of long-term survival, additional prospective, large, and multicenter studies are required to confirm our results.

N-TproBNP as biomarker in systemic sclerosis

Systemic sclerosis (SSc) is a connective tissue disorder characterized by tissue fibrosis affecting the skin and internal organs, fibroproliferative vasculopathy, and autoimmune activation. SSc still heralds a poor prognosis with significant morbidity and mortality. Early detection of organ involvement is critical as currently available treatments are most effective when started early. Many candidate biomarkers have been investigated in the past two decades. However, despite the enormous efforts, no accurate tool to predict the pattern of organ involvement and to assess disease activity has been yet identified. The N-terminal fragment of probrain natriuretic peptide (N-TproBNP) is a neurohormone released by ventricular myocytes in response to pressure overload. N-TproBNP is highly relevant for diagnosis, prognosis, and prediction of pulmonary arterial hypertension in SSc. Moreover, several studies support its potential benefit for cardiac assessment of scleroderma patients. Conversely, the role of N-TproBNP as surrogate marker of pulmonary fibrosis and skin involvement is much less clear. We provide an extensive review of the studies that have previously investigated the role of N-TproBNP as candidate biomarker in scleroderma manifestations, presenting also the findings of a recent study we conducted in a cohort of 87 SSc patients.