Noninvasive ventilation in acute cardiogenic pulmonary edema: a meta-analysis of randomized controlled trials

Diagnosis and Management of Acute Respiratory Failure

Acute hypoxemic respiratory failure is defined by Pao2 less than 60 mm Hg or SaO2 less than 88% and may result from V/Q mismatch, shunt, hypoventilation, diffusion limitation, or low inspired oxygen tension. Acute hypercapnic respiratory failure is defined by Paco2 ≥ 45 mm Hg and pH less than 7.35 and may result from alveolar hypoventilation, increased fraction of dead space, or increased production of carbon dioxide. Early diagnostic maneuvers, such as measurement of SpO2 and arterial blood gas, can differentiate the type of respiratory failure and guide next steps in evaluation and management.

Analysis of the effect of CPAP on hemodynamics using clinical data and a theoretical model: CPAP therapy decreases cardiac output mechanically but increases it via afterload reduction

BACKGROUND

Noninvasive positive pressure ventilation (NIPPV) has been established as an effective treatment for heart failure. Positive airway pressure such as continuous positive airway pressure (CPAP) increases cardiac output (CO) in some patients but decreases it in others. However, the mechanism behind such unpredictable responses remains undetermined.

METHODS AND RESULTS

We measured hemodynamic parameters of 38 cases using Swan-Ganz catheter before and after CPAP in chronic heart failure status. In those whose CO increased by CPAP, pulmonary vascular resistance (PVR) was significantly decreased and SpO2 significantly increased, but the other parameters were not changed. On the other hand, PVR was not changed, but systemic vascular resistance (SVR) was increased in those whose CO decreased by CPAP. To explain this phenomenon, we simulated the cardiovascular system using a cardiac model of time-varying elastance. In this model, it was indicated that CPAP decreases CO irrespective of cardiac function or filling status under constant PVR condition. However, when reduction of PVR by CPAP was taken into account, an increase in CO was expected especially in the hypervolemic and low right ventricle (RV) systolic function cases.

CONCLUSIONS

CPAP would increase CO only where PVR can be reduced by CPAP therapy, especially in the case with hypervolemia and/or low RV systolic function. Understanding the underlying mechanism should help identify the patients for whom NIPPV would be effective.

Advantages and drawbacks of helmet noninvasive support in acute respiratory failure

INTRODUCTION

Non-invasive ventilation (NIV) represents an effective strategy for managing acute respiratory failure. Facemask NIV is strongly recommended in acute exacerbation of chronic obstructive pulmonary disease (AECOPD) with hypercapnia and acute cardiogenic pulmonary edema (ACPE). Its role in managing acute hypoxemic respiratory failure (AHRF) remains a debated issue. NIV and continuous positive airway pressure (CPAP) delivered through the helmet are recently receiving growing interest for AHRF management.

AREAS COVERED

In this narrative review, we discuss the clinical applications of helmet support compared to the other available noninvasive strategies in the different phenotypes of acute respiratory failure.

EXPERT OPINION

Helmets enable the use of high positive end-expiratory pressure, which may protect from self-inflicted lung injury: in AHRF, the possible superiority of helmet support over other noninvasive strategies in terms of clinical outcome has been hypothesized in a network metanalysis and a randomized trial, but has not been confirmed by other investigations and warrants confirmation. In AECOPD patients, helmet efficacy may be inferior to that of face masks, and its use prompts caution due to the risk of CO₂ rebreathing. Helmet support can be safely applied in hypoxemic patients with ACPE, with no advantages over facemasks.

Treatment of acute respiratory failure: noninvasive mechanical ventilation

Background: Noninvasive ventilation (NIV) has been an important strategy to support patients with respiratory failure, while preventing complications assorted with invasive mechanical ventilation. Physicians need to be aware of the various roles of NIV and the challenges encountered in clinical practice.Current Concepts: Traditionally, the application of NIV has been well-known to be associated with reduced mortality in patients with chronic obstructive pulmonary disease (COPD) or acute pulmonary edema and those suffering from acute respiratory failure. However, despite some positive results of NIV treatment in patients with de novo hypoxemic respiratory failure such as acute pneumonia or acute respiratory distress syndrome, NIV failure (or delayed intubation) can have deleterious effects on patients outcomes. Besides, the aggravation of lung injury should also be taken into consideration when applied to patients exhibiting high respiratory drive. Nonetheless, NIV has potential for wide applications in various clinical situations such as facilitation of ventilator weaning, post-operative respiratory failure, or palliative treatment.Discussion and Conclusion: In addition to the strong evidence in patients with acute respiratory failure due to COPD or acute pulmonary edema, the NIV treatment can be potentially used for various clinical conditions. However, compared to European countries, the prevalence of NIV use continues to remain lower in South Korea. Nevertheless, when applied in appropriately selected patients in a timely manner, NIV treatment can be associated with improved patient outcomes.

Non-invasive Positive Pressure Ventilation for Acute Cardiogenic Pulmonary Edema and Chronic Obstructive Pulmonary Disease in Prehospital and Emergency Settings

Non-invasive ventilation is an important intervention in treating acute respiratory failure caused by acute cardiogenic pulmonary edema (ACPE) and acute exacerbations of chronic obstructive pulmonary disease (COPD). Although there are studies that give evidence on the efficacy and safety of non-invasive ventilation over standard medical care for COPD and cardiogenic pulmonary edema, less are known about the form of non-invasive ventilation, continuous positive airway pressure (CPAP), or bilevel positive airway pressure (BiPAP) as an effective intervention for respiratory failure and its efficacy and safety in prehospital settings. We conducted a systematic review by using PubMed and Google Scholar as databases for collecting studies related to the effectiveness of CPAP and BiPAP for cardiogenic pulmonary edema and COPD; the major outcome studied was reducing rates of endotracheal intubation secondary and tertiary outcomes included mortality reduction and shortening length of hospital stay. The study follows the guidelines of the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) checklist 2009. Sixteen studies were identified, including systematic reviews, randomized control trials, and observational studies. Studies published on or after 2010 in a population greater than 40 years old suffering from acute COPD and cardiogenic pulmonary edema were taken for review. Studies that described other respiratory diseases treated with non-invasive ventilation were excluded. Quality appraisal was done using the Cochrane risk bias tool for randomized control trials, Amstar-2 for systematic reviews, and New Castle Ottawa Tool for observational studies. Five studies compared the effectiveness of CPAP and BiPAP with standard medical care in prehospital and emergency settings. Six studies described prehospital intervention. Both forms of non-invasive ventilation were equally significant and effective. Prehospital use had tremendously reduced intubation rates, with not much variability noticed for mortality and hospital stay. Non-invasive ventilation is an effective measure for respiratory failure secondary to COPD and ACPE. Early out of hospital utilization of CPAP and BiPAP reduces the rate of invasive ventilation and reduces complications due to endotracheal intubation. Endotracheal intubation is associated with a considerable incidence of complications like failed intubation, hypotension, or circulatory arrest, even if the emergency physician is well trained, making these forms of non-invasive ventilation safe and effective interventions in the prehospital settings.

Butorphanol versus Propofol in Patients Undergoing Noninvasive Ventilation: A Prospective Observational Study

Background

The present study aimed to explore sedation management in agitated patients who suffered from acute respiratory failure (ARF) and were treated with noninvasive ventilation (NIV).

Patients and Methods

We divided 118 patients undergoing NIV treatment with butorphanol or propofol into two groups: group B (n = 57, butorphanol was initiated at the rate of 0.12 µg/kg/min as a continuous intravenous infusion and then titrated by 0.06 µg/kg/min every half an hour, group P (n = 61, propofol was initiated at the rate of 5 µg/kg/min as a continuous intravenous infusion and then titrated by 1.5 µg/kg/min every half an hour). Score of Sedation Agitation Scale (SAS) in the two groups was maintained between 3 and 4. Medications including sedative, analgesic, and antipsychotic, NIV intolerance score, SAS score, visual analog scale (VAS), medication use and adverse events were recorded repeatedly.

Results

Patients receiving butorphanol required significantly less total amount of fentanyl than patients receiving propofol during NIV to maintain the target VAS [0 (0–0) µg vs 150 (50–200) µg, P< 0.005]. Hemodynamic stability during NIV showed it was better kept in patients treated with butorphanol.

Conclusion

Butorphanol not only decreased the requirements of fentanyl but also enhanced hemodynamic stability in agitated patients suffering from ARF receiving NIV.

Trial Registration

Registered at http://www.chictr.org.cn/ (ChiCTR1800015534).

Prehospital arterial hypercapnia in acute heart failure is associated with admission to acute care units and emergency room length of stay: a retrospective cohort study

BACKGROUND

Acute Heart Failure (AHF) is a common condition that often presents with acute respiratory distress and requires urgent medical evaluation and treatment. Arterial hypercapnia is common in AHF and has been associated with a higher rate of intubation and non-invasive ventilation in the Emergency Room (ER), but its prognostic value has never been studied in the prehospital setting.

METHODS

A retrospective study was performed on the charts of all patients taken care of by a physician-staffed prehospital mobile unit between June 2016 and September 2019 in Geneva. After approval by the ethics committee, charts were screened to identify all adult patients with a diagnosis of AHF in whom a prehospital arterial blood gas (ABG) sample was drawn. The main predictor was prehospital hypercapnia. The primary outcome was the admission rate in an acute care unit (ACU, composite of intensive care and high-dependency units). Secondary outcomes were ER length of stay (LOS), orientation from ER (intensive care unit, high-dependency unit, general ward, discharge home), intubation rate at 24 h, hospital LOS and hospital mortality.

RESULTS

A total of 106 patients with a diagnosis of AHF were analysed. Hypercapnia was found in 61 (58%) patients and vital signs were more severely altered in this group. The overall ACU admission rate was 48%, with a statistically significant difference between hypercapnic and non-hypercapnic patients (59% vs 33%, p = 0.009). ER LOS was shorter in hypercapnic patients (5.4 h vs 8.9 h, p = 0.016).

CONCLUSIONS

There is a significant association between prehospital arterial hypercapnia, acute care unit admission, and ER LOS in AHF patients.

Indications for Non-Invasive Ventilation in Respiratory Failure

BACKGROUND

Non-invasive ventilation (NIV) is increasingly being used to treat episodes of acute respiratory failure not only in critical care and respiratory wards, but also in emergency departments.

AIM

Aim of this review is to summarize the current indications for the management of NIV for respiratory failure.

METHODS

Current literature about the topic was reviewed and critically reported to describe the rationale and physiologic advantages of NIV in various situations of respiratory failure.

RESULTS

Early NIV use is commonly associated with the significant decrease in endotracheal intubation rate, the incidence of infective complications (especially ventilatory associated pneumonia), Intensive Care Units and the length of hospital stay and, in selected conditions, also in mortality rates. Severe acute exacerbation of chronic obstructive pulmonary disease (pH<7.35 and relative hypercarbia) and acute cardiogenic pulmonary oedema are the most common NIV indications; in these conditions NIV advantages are clearly documented. Not so evident are the NIV benefits in hypoxaemic respiratory failure occurring without prior chronic respiratory disease (De novo respiratory failure). One recent randomized control trial reported in hypoxaemic respiratory failure a survival benefit of high-flow nasal cannulae over standard oxygen therapy and bilevel NIV. Evidence suggests the advantages of NIV also in respiratory failure in immunocompromised patients or chest trauma patients. Use during a pandemic event has been assessed in several observational studies but remains controversial; there also is not sufficient evidence to support the use of NIV treatment in acute asthma exacerbation.

CONCLUSION

NIV eliminates morbidity related to the endotracheal tube (loss of airway defense mechanism with increased risk of pneumonia) and in selected conditions (COPD exacerbation, acute cardiogenic pulmonary edema, immunosuppressed patients with pulmonary infiltrates and hypoxia) is clearly associated with a better outcome in comparison to conventional invasive ventilation. However, NIV is associated with complications, especially minor complications related to interface. Major complications like aspiration pneumonia, barotrauma and hypotension are infrequent.

Continuous positive airway pressure (CPAP) provision with a pediatric helmet for treatment of hypoxemic acute respiratory failure in dogs

OBJECTIVE

To evaluate arterial blood gas parameters and pulmonary radiography, before and after provision of continuous positive airway pressure (CPAP) via a pediatric helmet in dogs with acute hypoxemic respiratory failure.

DESIGN

Single-center, observational study conducted from 2016 to 2017.

SETTING

University teaching hospital.

ANIMALS

Seventeen dogs presenting with clinical signs compatible with respiratory failure, confirmed by arterial blood gas analyses.

INTERVENTIONS

For each animal arterial blood samples and thoracic radiographs were performed at arrival (T₀ ). Hypoxemic dogs (PaO₂  <80 mm Hg), without evidence of pneumothorax or pleural effusion, received CPAP ventilation via a pediatric Helmet for at least 1 hour. At the end of CPAP ventilation, a second arterial blood gas analysis was performed at room air (T₁ ). The F-shunt was also calculated.

MEASUREMENT AND MAIN RESULTS

Respiratory rate, heart rate and rhythm, mean blood pressure, mucosal membrane color, and rectal temperature were recorded. Tolerance to the helmet was evaluated using a predetermined scoring system. Two dogs were excluded from the study for low tolerance to the helmet. In 15 of 17 dogs, a significant difference between T₀ and T₁ was noted for PaO₂ (60.84 ± 3 mm Hg vs 80.2 ± 5.5 mm Hg), P(A-a)O₂ (52.4 ± 4.4 mm Hg vs 35.2 ± 6 mm Hg), PaO₂ /FiO₂ (289.7 ± 14.3 vs 371 ± 21), and %SO₂ (91.3 vs 98.8). In 15 of 17 dogs, the helmet was well tolerated. F-shunt significantly decreased following provision of CPAP (37%; range, 8.4-68% vs 6%; range, -5.6-64.3%).

CONCLUSION

The use of a pediatric helmet appears to be a suitable device for delivery of CPAP in dogs with hypoxemic acute respiratory failure. The device appears to be reasonably tolerated and improved oxygenation in most dogs.

Non-Invasive Ventilatory Support In the Elderly

PURPOSE OF REVIEW

The first description of non-invasive ventilation use began in the 1920s. Since then, its role in patient care has evolved through increased clinical knowledge and scientific advancements. The utilization of non-invasive ventilation has broadened from initial application in acute in-hospital ICU settings to now include the outpatient settings. This review discusses the history of non-invasive ventilation and its role in acute in-hospital chronic obstructive pulmonary disease (COPD) exacerbations, cardiogenic pulmonary edema, and weaning from mechanical ventilation in the elderly. The elderly population represents a significant portion of patients hospitalized for the aforementioned conditions. These groups often have more limitations related to the use of invasive mechanical ventilation (IMV), therefore, it is essential to understand the impact of non-invasive ventilation on hospital outcomes.

RECENT FINDINGS

There is strong clinical evidence supporting the use of non-invasive ventilation in patients with respiratory failure secondary to acute COPD exacerbations and cardiogenic pulmonary edema. When compared to standard medical management of these conditions, there is a consistent and significant reduction in the rate of endotracheal intubation and in-hospital mortality.

SUMMARY

The basis of noninvasive ventilation applicability has been determined by significant reduction in mortality and intubation rates. Although survival benefits have been observed, there still remain limitations to the clinical applicability of non-invasive ventilation in certain patient populations and conditions that require further investigation.

Benefits of non-invasive ventilation in acute hypercapnic respiratory failure

Non-invasive ventilation (NIV) with bilevel positive airway pressure is a non-invasive technique, which refers to the provision of ventilatory support through the patient's upper airway using a mask or similar device. This technique is successful in correcting hypoventilation. It has become widely accepted as the standard treatment for patients with hypercapnic respiratory failure (HRF). Since the 1980s, NIV has been used in intensive care units and, after initial anecdotal reports and larger series, a number of randomized trials have been conducted. Data from these trials have shown that NIV is a valuable treatment for HRF. This review aims to explore the principal areas in which NIV can be useful, focusing particularly on patients with acute HRF (AHRF). We will update the evidence base with the goal of supporting clinical practice. We provide a practical description of the main indications for NIV in AHRF and identify the group of patients with hypercapnic failure who will benefit most from the application of NIV.

Chinese society of cardiology expert consensus statement on the diagnosis and treatment of adult fulminant myocarditis

Fulminant myocarditis is primarily caused by infection with any number of a variety of viruses. It arises quickly, progresses rapidly, and may lead to severe heart failure or circulatory failure presenting as rapid-onset hypotension and cardiogenic shock, with mortality rates as high as 50%–70%. Most importantly, there are no treatment options, guidelines or an expert consensus statement. Here, we provide the first expert consensus, the Chinese Society of Cardiology Expert Consensus Statement on the Diagnosis and Treatment of Fulminant Myocarditis, based on data from our recent clinical trial (NCT03268642). In this statement, we describe the clinical features and diagnostic criteria of fulminant myocarditis, and importantly, for the first time, we describe a new treatment regimen termed life support-based comprehensive treatment regimen. The core content of this treatment regimen includes (i) mechanical life support (applications of mechanical respirators and circulatory support systems, including intraaortic balloon pump and extracorporeal membrane oxygenation, (ii) immunological modulation by using sufficient doses of glucocorticoid, immunoglobulin and (iii) antiviral reagents using neuraminidase inhibitor. The proper application of this treatment regimen may and has helped to save the lives of many patients with fulminant myocarditis.

Non-invasive ventilation in cardiogenic pulmonary edema

Cardiogenic pulmonary edema (CPE) is among the most common causes of acute respiratory failure (ARF) in the acute care setting and often requires ventilatory assistance. In patients with ARF due to CPE, use of non-invasive positive airway pressure can decrease the systemic venous return and the left ventricular (LV) afterload, thus reducing LV filling pressure and limiting pulmonary edema. In these patients, either non-invasive ventilation (NIV) or continuous positive airway pressure (CPAP) can improve vital signs and physiological parameters, decreasing the need for endotracheal intubation (ETI) and hospital mortality when compared to conventional oxygen therapy. Results on the use of NIV or CPAP in patients with CPE prior to hospitalization are not homogeneous among studies, hampering any conclusive recommendation regarding their role in the pre-hospital setting.

Official ERS/ATS clinical practice guidelines: noninvasive ventilation for acute respiratory failure

Noninvasive mechanical ventilation (NIV) is widely used in the acute care setting for acute respiratory failure (ARF) across a variety of aetiologies. This document provides European Respiratory Society/American Thoracic Society recommendations for the clinical application of NIV based on the most current literature.The guideline committee was composed of clinicians, methodologists and experts in the field of NIV. The committee developed recommendations based on the GRADE (Grading, Recommendation, Assessment, Development and Evaluation) methodology for each actionable question. The GRADE Evidence to Decision framework in the guideline development tool was used to generate recommendations. A number of topics were addressed using technical summaries without recommendations and these are discussed in the supplementary material.This guideline committee developed recommendations for 11 actionable questions in a PICO (population-intervention-comparison-outcome) format, all addressing the use of NIV for various aetiologies of ARF. The specific conditions where recommendations were made include exacerbation of chronic obstructive pulmonary disease, cardiogenic pulmonary oedema, de novo hypoxaemic respiratory failure, immunocompromised patients, chest trauma, palliation, post-operative care, weaning and post-extubation.This document summarises the current state of knowledge regarding the role of NIV in ARF. Evidence-based recommendations provide guidance to relevant stakeholders.

Official ERS/ATS clinical practice guidelines: noninvasive ventilation for acute respiratory failure

Noninvasive mechanical ventilation (NIV) is widely used in the acute care setting for acute respiratory failure (ARF) across a variety of aetiologies. This document provides European Respiratory Society/American Thoracic Society recommendations for the clinical application of NIV based on the most current literature.The guideline committee was composed of clinicians, methodologists and experts in the field of NIV. The committee developed recommendations based on the GRADE (Grading, Recommendation, Assessment, Development and Evaluation) methodology for each actionable question. The GRADE Evidence to Decision framework in the guideline development tool was used to generate recommendations. A number of topics were addressed using technical summaries without recommendations and these are discussed in the supplementary material.This guideline committee developed recommendations for 11 actionable questions in a PICO (population-intervention-comparison-outcome) format, all addressing the use of NIV for various aetiologies of ARF. The specific conditions where recommendations were made include exacerbation of chronic obstructive pulmonary disease, cardiogenic pulmonary oedema, de novo hypoxaemic respiratory failure, immunocompromised patients, chest trauma, palliation, post-operative care, weaning and post-extubation.This document summarises the current state of knowledge regarding the role of NIV in ARF. Evidence-based recommendations provide guidance to relevant stakeholders.

Adaptive servo-ventilation therapy reduces hospitalization rate in patients with severe heart failure

INTRODUCTION

Adaptive servo-ventilation (ASV) therapy is a recently developed non-pharmacological therapy that has been reported to improve cardiac function and survival in patients with severe congestive heart failure (CHF). However, a recent large randomized study suggested that ASV does not improve survival in patients with reduced ejection fraction. It remains unclear whether ASV treatment can reduce the hospitalization rate of CHF patients. We thus examined the frequency of hospital admission before and after initiation of ASV therapy in patients with CHF.

METHODS AND RESULTS

Hospitalization frequencies during the 12months before and 12months after initiation of ASV therapy (24 consecutive months) were retrospectively compared in 44 consecutive patients with severe CHF. The admission frequency decreased from 1.9±1.4 admissions in the 12months before ASV to 1.1±1.6 admissions in the 12months after ASV initiation (P<0.001). The decrease tended to be greater in those patients with more frequent hospitalizations before ASV initiation.

CONCLUSION

ASV therapy reduces hospital admissions in patients with severe CHF who are receiving maximum medical treatment.

Delirium is a Strong Predictor of Mortality in Patients Receiving Non-invasive Positive Pressure Ventilation

PURPOSE

Non-invasive positive pressure ventilation (NIPPV) has gained popularity over the years in the treatment of acute respiratory failure (ARF). Preliminary evidence suggests that delirium is an important factor contributing to NIPPV failure and death. This study was conducted to evaluate delirium and other associated factors of deaths in patients with ARF requiring the use of NIPPV.

METHODS

A prospective observational study was conducted in a specialised NIPPV unit. Consecutive patients admitted for ARF requiring NIPPV were assessed by a psychiatrist for presence of delirium using the Diagnostic and Statistical Manual Version IV (DSM-IV). APACHE II score, co-morbidities-, and lung function were also assessed. Patients were followed until their deaths for a minimum of 1 year. Univariate and multivariate Cox's regression analyses were performed to explore predictive factors for death.

RESULTS

A total of 153 subjects were recruited, 49 (32.0 %) of whom had delirium. On univariate analysis, higher APACHE II score, lower BMI, presence of delirium, higher Charlson's co-morbidity index but not FEV₁ were associated with earlier death. On multivariate analysis, delirium (HR 4.4; 95 % CI 2.6-7.4; p < 0.001) and lower BMI (HR 0.92; 95 % CI 0.86-0.98; p = 0.013) were independently associated with earlier death within 1 year.

CONCLUSIONS

There is a high prevalence of delirium in patients requiring NIPPV. The presence of delirium is a strong predictor of mortality. There is strong need to identify and manage these high-risk patients to improve their mortality. The collaboration between psychiatrists and physicians should be strengthened.

Noninvasive ventilation on mortality of acute respiratory distress syndrome

[Purpose] The aim of this study was to assess the efficacy of noninvasive ventilation (NIV) in acute respiratory distress syndrome (ARDS). [Subjects and Methods] The clinical data of 58 patients with ARDS that required mechanical ventilation in two intensive care units (ICU) was reviewed. [Results] Endotracheal intubation was performed in 55.17% of the total patients and in 39.53% of the patients who received NIV treatment. The APACHE II score for patients who only received IV was significantly higher than those who only underwent NIV (25.67 ± 5.30 vs. 18.12 ± 7.20). However, there were no significant differences in 28-day/90-day survival rates, duration of mechanical ventilation, and length of ICU stay between these two groups. For patients from a NIV-to-IV group, the APACHE II scores before endotracheal intubation were higher than the scores from IV patients (26.12 ± 4.08 vs. 21.94 ± 6.10). The 90-day survival rate in the NIV-to-IV group was significantly lower than that of the IV-only group (23.5% vs. 73.3%), although there was no difference in the 28-day survival rate between the two groups. [Conclusion] The application of NIV reduces the percentage of patients requiring endotracheal intubation.

Experience of acute noninvasive ventilation-insights from 'Behind the Mask': a qualitative study

OBJECTIVE

Non-invasive ventilation (NIV) is widely used in the management of acute and acute-on-chronic respiratory failure. Understanding the experiences of patients treated with NIV is critical to person-centred care. We describe the subjective experiences of individuals treated with NIV for acute hypercapnic respiratory failure.

DESIGN

Qualitative face-to-face interviews analysed using thematic analysis.

SETTING

Australian tertiary teaching hospital.

PARTICIPANTS

Individuals with acute hypercapnic respiratory failure treated with NIV outside the intensive care unit. Individuals who did not speak English or were unable or unwilling to consent were excluded.

RESULTS

13 participants were interviewed. Thematic saturation was achieved. Participants described NIV providing substantial relief from symptoms and causing discomfort. They described enduring NIV to facilitate another chance at life. Although participants sometimes appeared passive, others expressed a strong conviction that they knew which behaviours and treatments relieved their distress. Most participants described gaps in their recollection of acute hospitalisation and placed a great amount of trust in healthcare providers. All participants indicated that they would accept NIV in the future, if clinically indicated, and often expressed a sense of compulsion to accept NIV. Participants' description of their experience of NIV was intertwined with their experience of chronic disease.

CONCLUSIONS

Participants described balancing the benefits and burdens of NIV, with the goal of achieving another chance at life. Gaps in recall of their treatment with NIV were frequent, potentially suggesting underlying delirium. The findings of this study inform patient-centred care, have implications for the care of patients requiring NIV and for advance care planning discussions.

Acidemia in severe acute cardiogenic pulmonary edema treated with noninvasive pressure support ventilation: a single-center experience

In clinical practice, acidotic patients with acute cardiogenic pulmonary edema (ACPE) are commonly considered more severe in comparison with nonacidotic patients, and data on the outcome of these patients treated with noninvasive pressure support ventilation (NIV) are lacking.The present investigation was aimed at assessing whether acidosis on admission (pH < 7.35) was associated with adverse outcome in 65 consecutive patients with ACPE treated with NIV and admitted to our Intensive Cardiac Care Unit (ICCU).In our population, 28 patients were acidotic (28 of 65, 43.1%), whereas 41 patients were not (37 of 65, 56.9%). According to the Repeated Measures General Linear Model, pCO2 values significantly changed throughout the 2-h NIV treatment (P = 0.019) in both groups (P = 0001). In acidotic patients, pCO2 significantly decreased (51.9 ± 15.3 → 47.0 ± 12.8 → 44.8 ± 12.7), whereas they increased in the nonacidotic subgroup (36.8 ± 6.5 → 36.9 ± 7.2 → 37.6 ± 6.4). No difference was observed in intubation rate between acidotic (eight patients, 28.6%) and nonacidotic patients (12 patients, 32.4%) (P = 0.738). In-ICCU mortality rate did not differ between (13 patients, 35.1%) and nonacidotic patients (nine patients, 32.1%) (P = 0.801).Our data strongly suggest that in patients with severe ACPE treated with NIV, the presence of acidosis is not associated with adverse outcomes (early mortality and intubation rates) in these patients.

Portable Monitoring for the Diagnosis of OSA

In-laboratory, attended polysomnography has long been the gold standard for the diagnosis of sleep-disordered breathing (SDB). In recent years, economic pressures and long wait times have driven interest in home sleep testing, which has, in turn, led to the development of algorithms that bypass the sleep laboratory in favor of portable monitoring studies and in-home initiation of positive airway pressure therapy. For appropriately selected outpatients, evidence is accumulating that portable monitors are a reasonable substitute for in-laboratory polysomnography. In the inpatient setting, in which SDB is both highly prevalent and associated with adverse outcomes in certain populations, the literature is evolving on the use of portable monitors to expedite diagnosis and treatment of SDB. This review discusses society guidelines and recent research in the growing field of portable monitoring.

[Key messages for the initial management of the elderly patient with acute heart failure]

Acute heart failure is a high prevalence geriatric syndrome that has become one of the most frequent causes of visits to emergency departments, as well as hospital admission, and is associated with high morbidity, mortality and functional impairment. There has been an increasing amount of information published in recent years on the initial management of acute heart failure and the results of the short-term outcomes, as well as the natural history of the disease. The objective of this study is to provide several recommendations that should be taken into account in the initial management of the elderly patient with acute heart failure in the emergency departments, and to review the most interesting currently on-going clinical trials.

De novo acute heart failure and acutely decompensated chronic heart failure

BACKGROUND

Heart failure is one of the most common diseases of adults in Europe, with an overall prevalence of 1-2%. Among persons aged 60 and above, its prevalence is above 10% in men and 8% in women. Acute heart failure has a poor prognosis; it is associated with a high rate of rehospitalization and a 1-year mortality of 20-30%.

METHODS

This review is based on pertinent literature, including guidelines, retrieved by a selective search in PubMed.

RESULTS

There are different types of acute heart failure; the basic diagnostic assessment is performed at once and consists of ECG, echocardiography, and the measurement of N-terminal pro-brain natriuretic peptide (NTproBNP) and troponin levels. The most common causes of decompensation are arrhythmia, valvular dysfunction, and acute cardiac ischemia, each of which accounts for 30% of cases. The potential indication for immediate revascularization should be carefully considered in cases where acute heart failure is due to coronary heart disease. The basic treatment of acute heart failure is symptomatic, with the administration of oxygen, diuretics, and vasodilators. Ino-tropic agents, vasopressors, and temporary mechanical support for the circulatory system are only used to treat cardiogenic shock.

CONCLUSION

The treatment of acute heart failure is markedly less evidence-based than that of chronic heart failure. Newer treatment approaches that are intended to improve outcomes still need to be tested in multicenter trials.

Non-invasive mechanical ventilation in patients with diffuse interstitial lung diseases

Background

To evaluate noninvasive ventilation (NIV) in diffuse interstitial lung diseases (DILD) patients with acute respiratory failure (ARF) according to baseline radiological patterns and the etiology of ARF.

Methods

In a multicenter, observational, retrospective study, consecutive DILD patients undergoing NIV because of an episode of ARF were evaluated in six Italian high dependency units. Three groups of patients were identified based on the etiology of ARF: those with pneumonia (Group A), those with acute exacerbation of fibrosis, (Group B) and those with other triggers (Group C). Clinical failure was defined as any among in-hospital mortality, endotracheal intubation and extra-corporeal membrane oxygenation use.

Results

Among the 60 patients enrolled (63% males; median age: 71 years), pneumonia (42%) and acute exacerbation of fibrosis (39%) were the two most frequent causes of ARF. A significant increase of PaO₂/FiO₂ ratio during NIV treatment was detected in Group A (p = 0.010), but not in Group B. No significant difference in PaO₂/FiO₂ ratio, PaCO₂ and pH values during NIV treatment was detected in patients with a radiological pattern of usual interstitial pneumonia (UIP) and non-specific interstitial pneumonia (NSIP). 22 patients (37%) suffered for a clinical failure. No significant differences in the study outcome were detected in Group A vs. Group B, as well as among patients with a radiological pattern of UIP vs. NSIP.

Conclusions

NIV treatment should be individualized in DILD patients with ARF according to the etiology, but not the baseline radiological pattern, in order to improve oxygenation.

Helmet CPAP vs. oxygen therapy in severe hypoxemic respiratory failure due to pneumonia

PURPOSE

The efficacy of noninvasive continuous positive airway pressure (CPAP) to improve outcomes in severe hypoxemic acute respiratory failure (hARF) due to pneumonia has not been clearly established. The aim of this study was to compare CPAP vs. oxygen therapy to reduce the risk of meeting criteria for endotracheal intubation (ETI).

METHODS

In a multicenter randomized controlled trial conducted in four Italian centers patients with severe hARF due to pneumonia were randomized to receive helmet CPAP (CPAP group) or oxygen delivered with a Venturi mask (control group). The primary endpoint was the percentage of patients meeting criteria for ETI, including either one or more major criteria (respiratory arrest, respiratory pauses with unconsciousness, severe hemodynamic instability, intolerance) or at least two minor criteria (reduction of at least 30% of basal PaO2/FiO2 ratio, increase of 20% of PaCO2, worsening of alertness, respiratory distress, SpO2 less than 90%, exhaustion).

RESULTS

Between February 2010 and 2013, 40 patients were randomized to CPAP and 41 to Venturi mask. The proportion of patients meeting ETI criteria in the CPAP group was significantly lower compared to those in the control group (6/40 = 15% vs. 26/41 = 63%, respectively, p < 0.001; relative risk 0.24, 95% CI 0.11-0.51; number needed to treat, 2) two patients were intubated in the CPAP group and one in the control group. The CPAP group showed a faster and greater improvement in oxygenation in comparison to controls (p < 0.001). In either study group, no relevant adverse events were detected.

CONCLUSIONS

Helmet CPAP reduces the risk of meeting ETI criteria compared to oxygen therapy in patients with severe hARF due to pneumonia.

Acute exacerbation of chronic obstructive pulmonary disease: cardiovascular links

Chronic obstructive pulmonary disease (COPD) is a chronic, progressive lung disease resulting from exposure to cigarette smoke, noxious gases, particulate matter, and air pollutants. COPD is exacerbated by acute inflammatory insults such as lung infections (viral and bacterial) and air pollutants which further accelerate the steady decline in lung function. The chronic inflammatory process in the lung contributes to the extrapulmonary manifestations of COPD which are predominantly cardiovascular in nature. Here we review the significant burden of cardiovascular disease in COPD and discuss the clinical and pathological links between acute exacerbations of COPD and cardiovascular disease.

Continuous positive airway pressure (CPAP) may not reduce short-term mortality in cardiogenic pulmonary edema: a propensity-based analysis

INTRODUCTION

Continuous positive airway pressure (CPAP) improves patients' condition in case of cardiogenic pulmonary edema (CPE). However, the impact of CPAP on short-term mortality remains a matter of debate. We aimed at estimating the effect of CPAP on short-term mortality in patients treated for a CPE.

METHODS AND RESULTS

We pooled the data from the Acute Heart Failure Global Registry of Standard Treatment and the Etude Francaise l'Innsuficiens Cardiaque Aigue observational cohorts to compare the estimations of the effect on short-term mortality of CPAP, before and after propensity score (PS) matching. A total of 2286 patients with a cardiogenic pulmonary edema were included in the analysis, of whom 321 (14%) received CPAP. Of these, 314 could be matched to a control patient (matched population: n = 628) and were included in the PS analysis. In naive analysis, CPAP application influenced neither short-term mortality (HR: 1.03, 95% CI: 0.73-1.46; P = .86) nor the need for tracheal intubation (OR: 1.04, 95% CI: 0.78-1.40; P = .78). After PS matching, CPAP was associated with a reduction in the need for tracheal intubation (OR: 0.56, 95% CI: 0.37-0.84; P = .005) but it did not reduce short-term mortality (HR: 0.77, 95% CI: 0.47-1.26; P = .30).

CONCLUSIONS

Despite a reduction in the need for tracheal intubation, CPAP application may not reduce short-term mortality in patients suffering from cardiogenic pulmonary edema.

Noninvasive ventilation in chest trauma: systematic review and meta-analysis

PURPOSE

Single studies of Noninvasive Ventilation (NIV) in the management of acute respiratory failure in chest trauma patients have produced controversial findings. The aim of this study is to critically review the literature to investigate whether NIV reduces mortality, intubation rate, length of stay and complications in patients with chest trauma, compared to standard therapy.

METHODS

We performed a systematic review and meta-analysis of randomized controlled trials, prospective and retrospective observational studies, by searching PubMed, EMBASE and bibliographies of articles retrieved. We screened for relevance studies that enrolled adults with chest trauma who developed mild to severe acute respiratory failure and were treated with NIV. We included studies reporting at least one clinical outcome of interest to perform a meta-analysis.

RESULTS

Ten studies (368 patients) met the inclusion criteria and were included for the meta-analysis. Five studies (219 patients) reported mortality and results were quite homogeneous across studies, with a summary relative risk for patients treated with NIV compared with standard care (oxygen therapy and invasive mechanical ventilation) of 0.26 (95 % confidence interval 0.09-0.71, p = 0.003). There was no advantage in mortality of continuous positive airway pressure over noninvasive pressure support ventilation. NIV significantly increased arterial oxygenation and was associated with a significant reduction in intubation rate, in the incidence of overall complications and infections.

CONCLUSIONS

These results suggest that NIV could be useful in the management of acute respiratory failure due to chest trauma.

Prehospital continuous positive airway pressure for acute respiratory failure: a systematic review and meta-analysis

INTRODUCTION

Acute respiratory failure (ARF) is a common problem encountered by emergency medical services and is associated with significant morbidity, mortality, and health care costs. Continuous positive airway pressure (CPAP) is an integral part of the hospital treatment of acute ARF, predominantly because of congestive heart failure. Intuitively, better patient outcomes may be achieved when CPAP is applied early in the prehospital setting, but there are few outcome studies to validate its use in this setting.

OBJECTIVE

This systematic review and meta-analysis aimed to examine the effectiveness of CPAP in the prehospital setting for patients with ARF.

METHODS

A literature review of bibliographic databases and secondary sources was conducted and potential papers were assessed by two independent reviewers. Included studies were those that compared CPAP therapy (and usual care) with no CPAP for ARF in the prehospital setting. Studies of other methods of noninvasive ventilation were not included. Methodologic quality was assessed using guidelines from the Cochrane Collaboration. Outcomes included the number of intubations, mortality, physiologic parameters, and dyspnea score. Forrest plots were constructed to estimate the pooled effect of CPAP on outcomes.

RESULTS

Five studies (1,002 patients) met the selection criteria--three randomized controlled trials (RCTs), a nonrandomized comparative study, and a retrospective comparative study using chart review. Forty-seven percent of the patients were allocated to the CPAP group. Baseline characteristics were similar between groups. The pooled estimates demonstrated significantly fewer intubations (odds ratio [OR] 0.31; 95% confidence interval [CI] 0.19-0.51) and lower mortality (OR 0.41; 95% CI 0.19-0.87) in the CPAP group.

CONCLUSION

The studies included in this review showed a reduction in the number of intubations and mortality in patients with ARF who received CPAP in the prehospital setting. The results may not be applicable to other health care contexts because of the inherent differences in the organization and staffing of the EMS systems. Information from large RCTs on the efficacy of CPAP initiated early in the prehospital setting is critical to establishing the evidence base underpinning this therapy before ambulance services incorporate CPAP as routine clinical practice.