Acute respiratory failure in patients with severe community-acquired pneumonia. A prospective randomized evaluation of noninvasive ventilation

[Non-invasive Mechanical Ventilation in Acute Respiratory Failure. Clinical Practice Guidelines - on behalf of the German Society of Pneumology and Ventilatory Medicine]

The guideline update outlines the advantages as well as the limitations of NIV in the treatment of acute respiratory failure in daily clinical practice and in different indications.Non-invasive ventilation (NIV) has a high value in therapy of hypercapnic acute respiratory failure, as it significantly reduces the length of ICU stay and hospitalization as well as mortality.Patients with cardiopulmonary edema and acute respiratory failure should be treated with continuous positive airway pressure (CPAP) and oxygen in addition to necessary cardiological interventions. This should be done already prehospital and in the emergency department.In case of other forms of acute hypoxaemic respiratory failure with only mild or moderately disturbed gas exchange (PaO2/FiO2 > 150 mmHg) there is no significant advantage or disadvantage compared to high flow nasal oxygen (HFNO). In severe forms of ARDS NIV is associated with high rates of treatment failure and mortality, especially in cases with NIV-failure and delayed intubation.NIV should be used for preoxygenation before intubation. In patients at risk, NIV is recommended to reduce extubation failure. In the weaning process from invasive ventilation NIV essentially reduces the risk of reintubation in hypercapnic patients. NIV is regarded useful within palliative care for reduction of dyspnea and improving quality of life, but here in concurrence to HFNO, which is regarded as more comfortable. Meanwhile NIV is also recommended in prehospital setting, especially in hypercapnic respiratory failure and pulmonary edema.With appropriate monitoring in an intensive care unit NIV can also be successfully applied in pediatric patients with acute respiratory insufficiency.

New Guidelines for Severe Community-acquired Pneumonia

In 2023, the new European guidelines on severe community-acquired pneumonia, providing clinical practice recommendations for the management of this life-threatening infection, characterized by a high burden of mortality, morbidity, and costs for the society. This review article aims to summarize the principal evidence related to eight different questions covered in the guidelines, by also highlighting the future perspectives for research activity.

Predicting invasive mechanical ventilation in COVID 19 patients: A validation study

INTRODUCTION

The decision to intubate and ventilate a patient is mainly clinical. Both delaying intubation (when needed) and unnecessarily invasively ventilating (when it can be avoided) are harmful. We recently developed an algorithm predicting respiratory failure and invasive mechanical ventilation in COVID-19 patients. This is an internal validation study of this model, which also suggests a categorized "time-weighted" model.

METHODS

We used a dataset of COVID-19 patients who were admitted to Rabin Medical Center after the algorithm was developed. We evaluated model performance in predicting ventilation, regarding the actual endpoint of each patient. We further categorized each patient into one of four categories, based on the strength of the prediction of ventilation over time. We evaluated this categorized model performance regarding the actual endpoint of each patient.

RESULTS

881 patients were included in the study; 96 of them were ventilated. AUC of the original algorithm is 0.87-0.94. The AUC of the categorized model is 0.95.

CONCLUSIONS

A minor degradation in the algorithm accuracy was noted in the internal validation, however, its accuracy remained high. The categorized model allows accurate prediction over time, with very high negative predictive value.

Influence of different noninvasive oxygenation support devices on tidal volume

BACKGROUND

Multiple devices are available for noninvasive oxygenation support, including non-rebreather oxygen mask (O2-mask), high-flow oxygen through nasal cannula (HFNC), continuous positive airway pressure (CPAP), mask noninvasive ventilation (Mask-NIV) and helmet NIV (Helmet-NIV). As tidal volume is a key determinant of efficacy and safety during ventilatory support, we assessed whether it was influenced by the type of noninvasive oxygenation device.

METHODS

A bench study using a manikin with a realistic face connected to a lung simulator was performed. Six conditions were assessed: no device, O2-mask, HFNC, CPAP, Mask-NIV and Helmet-NIV. Three respiratory mechanics were simulated (normal, obstructive, restrictive), at three simulated efforts (low, moderate, respiratory distress). Flow was recorded at the lung simulator inlet and mouth pressure into the manikin mouth. The same devices were evaluated on healthy volunteers with tidal volume assessed by electrical impedance tomography (EIT).

RESULTS

Tidal volume was significantly influenced by oxygenation devices in bench model. As compared to O2-mask, HFNC and CPAP delivered significantly lower tidal volumes (440 ± 352 mL, 414 ± 333 mL and 377 ± 297 mL, respectively), while Mask-NIV or Helmet-NIV were associated with significantly higher tidal volumes (690 ± 321 mL and 652 ± 366 mL, respectively). Tidal volume was strongly correlated with the specific effect of each device on mouth pressure during inspiration: HFNC and CPAP were characterized by a negative PTPmouth (- 0.3 [- 0.8 to - 0.2] and - 0.7 [- 2.2 to - 0.5] cmH2O.sec/cycle, respectively), while Helmet-NIV and Mask-NIV were associated with a positive PTPmouth (4.5 [4.1-4.6] and 6.1 [5.9-7.1] cmH2O.sec/cycle, respectively). Tidal volume was also significantly influenced by oxygenation devices in healthy volunteers, with similar tidal volumes between O2-mask and CPAP (644 [571-764] and 648 [586-770] mL) but higher with HFNC, Mask-NIV and Helmet-NIV (819 [609-918], 1110 [661-1305] and 1086 [833-1243] mL).

CONCLUSIONS

Tidal volume is significantly influenced by noninvasive oxygenation support devices, with a strong correlation with the pressure variation generated into the mouth during inspiration. NIV was associated with the highest tidal volumes and CPAP with the lowest ones. Clinical studies are needed to clarify the clinical implications of these effects.

Noninvasive Oxygenation Strategies in Adult Patients With Acute Hypoxemic Respiratory Failure: A Systematic Review and Network Meta-Analysis

BACKGROUND

Several recently published randomized controlled trials have evaluated various noninvasive oxygenation strategies for the treatment of acute hypoxemic respiratory failure.

RESEARCH QUESTION

Which available noninvasive oxygen strategies are effective for acute hypoxic respiratory failure?

STUDY DESIGN AND METHODS

A systematic review of Medline, Embase, Cochrane CENTRAL, CINAHL, Web of Science, MedRxiv, and Research Square was conducted from inception to October 1, 2022. A random effects frequentist network meta-analysis was performed, and the results are presented using absolute risk difference per 1,000 patients. The Grading of Recommendations, Assessment, Development and Evaluation framework was used to rate the certainty of the evidence. Mortality, invasive mechanical ventilation, duration of hospitalization and ICU stay, ventilator-free days, and level of comfort are reported.

RESULTS

Thirty-six trials (7,046 patients) were included. It was found that helmet CPAP probably reduces mortality compared with standard oxygen therapy (SOT) (231 fewer deaths per 1,000; 95% CI, 126-273 fewer) (moderate certainty). A high-flow nasal cannula (HFNC) probably reduces the need for invasive mechanical ventilation (103.5 fewer events per 1,000; 95% CI, 40.5-157.5 fewer) (moderate certainty). All noninvasive oxygenation strategies may reduce the duration of hospitalization as compared with SOT (low certainty). Helmet bilevel ventilation (4.84 days fewer; 95% CI, 2.33-7.36 days fewer) and helmet CPAP (1.74 days fewer; 95% CI, 4.49 fewer-1.01 more) may reduce the duration of ICU stay as compared with SOT (both low certainty). SOT may be more comfortable than face mask noninvasive ventilation and no different in comfort compared with an HFNC (both low certainty).

INTERPRETATION

A helmet interface for noninvasive ventilation probably reduces mortality and the risk of mechanical ventilation, as well as the duration of hospital and ICU stay. An HFNC probably reduces the risk of invasive mechanical ventilation and may be as comfortable as SOT. Further research is necessary to understand the role of these interfaces in acute hypoxemic respiratory failure.

Predictors of Failure of Noninvasive Ventilation in Critically Ill Children

Noninvasive ventilation (NIV) is a common modality employed to treat acute respiratory failure. Most data guiding its use is extrapolated from adult studies. We sought to identify clinical predictors associated with failure of NIV, defined as requiring intubation. This single-center retrospective observational study included children admitted to pediatric intensive care unit (PICU) between July 2014 and June 2016 treated with NIV, excluding postextubation. A total of 148 patients was included. Twenty-seven (18%) failed NIV. There was no difference between the two groups with regard to age, gender, comorbidities, or etiology of acute respiratory failure. Those that failed had higher admission pediatric risk of mortality ( p  = 0.01) and pediatric logistic organ dysfunction ( p  = 0.002) scores and higher fraction of inspired oxygen (FiO 2 ; p  = 0.009) at NIV initiation. Failure was associated with lack of improvement in tachypnea. At 6 hours of NIV, the failure group had worsening tachypnea with a median increase in respiratory rate of 8%, while the success group had a median reduction of 18% ( p  = 0.06). Multivariable Cox's proportional hazard models revealed FiO 2 at initiation and worsening respiratory rate at 1- and 6-hour significant risks for failure of NIV. Failure was associated with a significantly longer PICU length of stay (success [2.8 days interquartile range (IQR): 1.7, 5.5] vs. failure [10.6 days IQR: 5.6, 13.2], p  < 0.001). NIV can be successfully employed to treat acute respiratory failure in pediatric patients. There should be heightened concern for NIV failure in hypoxemic patients whose tachypnea is unresponsive to NIV. A trend toward improvement should be closely monitored.

Acute dyspnea in the emergency department: a clinical review

Acute dyspnea represents one of the most frequent symptoms leading to emergency room evaluation. Its significant prognostic value warrants a careful evaluation. The differential diagnosis of dyspnea is complex due to the lack of specificity and the loose association between its intensity and the severity of the underlying pathological condition. The initial assessment of dyspnea calls for prompt diagnostic evaluation and identification of optimal monitoring strategy and provides information useful to allocate the patient to the most appropriate setting of care. In recent years, accumulating evidence indicated that lung ultrasound, along with echocardiography, represents the first rapid and non-invasive line of assessment that accurately differentiates heart, lung or extra-pulmonary involvement in patients with dyspnea. Moreover, non-invasive respiratory support modalities such as high-flow nasal oxygen and continuous positive airway pressure have aroused major clinical interest, in light of their efficacy and practicality to treat patients with dyspnea requiring ventilatory support, without using invasive mechanical ventilation. This clinical review is focused on the pathophysiology of acute dyspnea, on its clinical presentation and evaluation, including ultrasound-based diagnostic workup, and on available non-invasive modalities of respiratory support that may be required in patients with acute dyspnea secondary or associated with respiratory failure.

ERS/ESICM/ESCMID/ALAT guidelines for the management of severe community-acquired pneumonia

PURPOSE

Severe community-acquired pneumonia (sCAP) is associated with high morbidity and mortality, and whilst European and non-European guidelines are available for community-acquired pneumonia, there are no specific guidelines for sCAP.

METHODS

The European Respiratory Society (ERS), European Society of Intensive Care Medicine (ESICM), European Society of Clinical Microbiology and Infectious Diseases (ESCMID), and Latin American Thoracic Association (ALAT) launched a task force to develop the first international guidelines for sCAP. The panel comprised a total of 18 European and four non-European experts, as well as two methodologists. Eight clinical questions for sCAP diagnosis and treatment were chosen to be addressed. Systematic literature searches were performed in several databases. Meta-analyses were performed for evidence synthesis, whenever possible. The quality of evidence was assessed with GRADE (Grading of Recommendations, Assessment, Development and Evaluation). Evidence to Decision frameworks were used to decide on the direction and strength of recommendations.

RESULTS

Recommendations issued were related to diagnosis, antibiotics, organ support, biomarkers and co-adjuvant therapy. After considering the confidence in effect estimates, the importance of outcomes studied, desirable and undesirable consequences of treatment, cost, feasibility, acceptability of the intervention and implications to health equity, recommendations were made for or against specific treatment interventions.

CONCLUSIONS

In these international guidelines, ERS, ESICM, ESCMID, and ALAT provide evidence-based clinical practice recommendations for diagnosis, empirical treatment, and antibiotic therapy for sCAP, following the GRADE approach. Furthermore, current knowledge gaps have been highlighted and recommendations for future research have been made.

Survival Status and Predictors of Mortality Among Patients Admitted to Pediatric Intensive Care Unit at Selected Tertiary Care Hospitals in Ethiopia: A Prospective Observational Study

Background

Advances in pediatric intensive care have dramatically improved the prognosis for critically ill patients. The study aimed to determine the survival status and predictors of mortality among patients admitted to the pediatric intensive care unit at selected tertiary care hospitals in Ethiopia.

Methods

A health facility-based prospective observational study from October 2020 to May 30, 2021, was conducted in a selected tertiary care hospital in Ethiopia. Kaplan Meier was used to compare patient survival experiences and Cox regression was used to identify independent predictors of ICU mortality. The hazard ratio was used as a measure of the strength of the association, and a P-value of <.05 was considered to declare statistical significance.

Results

Of 206 study participants, 59 (28.6%) patients died during follow-up time, and the incidence of mortality was 3.6 deaths per 100 person-day observation (95% CI: 2.04-5.04 deaths per 100 person-days). Respiratory failure 19 (32.2%) was the commonest cause of death followed by septic shock 11(18.6). In-ICU complications (AHR: 2.13; 95% CI: 1.02, 4.42; P = .04), sepsis diagnosis (AHR: 2.43; 95% CI: 1.24, 4.78; P = .01), GCS < 8 (AHR: 1.96; 95% CI: 1.12, 3.43; P = .02), use of sedative drugs (AHR: 2.40; 95% CI: 1.16, 4.95; P = .02) were linked with increased risk of in-ICU mortality. In contrast, the use of mechanical ventilation was associated with decreased mortality (AHR: 0.45; 95% CI: 0.21, 0.92; P = .03).

Conclusion

The study found a high incidence of in-ICU mortality among admitted pediatric patients in selected Ethiopian tertiary care hospitals. In-ICU complications, sepsis diagnosis, GCS < 8, and patient use of sedative drugs were independent predictors of in-ICU mortality. Prudent follow-up is warranted for those patients with the aforementioned risk factors.

Noninvasive ventilation in patients with acute hypoxemic respiratory failure: a systematic review and meta-analysis of randomized controlled trials

The clinical benefits of noninvasive ventilation (NIV) for patients with acute hypoxemic respiratory failure (AHRF) is still inconclusive. We aimed to evaluate the effect of NIV compared with conventional oxygen therapy (COT)/high-flow nasal cannula (HFNC) in this patient population. We searched for relevant studies from PubMed, Embase, Cochrane Library, ClinicalTrials.gov, CINHAL, Web of Science up to August 2019 for randomized controlled trials (RCTs) that compared NIV with COT/HFNC in AHRF. The primary outcome was the tracheal intubation rate. Secondary outcomes were intensive care unit (ICU) mortality, and hospital mortality. We applied the GRADE approach to grade the strength of the evidence. Seventeen RCTs that recruited 1738 patients were included in our meta-analysis. When comparing NIV versus COT/HFNC, the pooled risk ratio (RR) for the tracheal intubation rate was 0.68, 95% confidence interval (CI) 0.52-0.89, p = 0.005, I² = 72.4%, low certainty of evidence. There were no significant differences in ICU mortality (pooled RR = 0.87, 95% CI 0.60-1.26), p = 0.45, I² = 64.6%) and hospital mortality (pooled RR = 0.71, 95% CI 0.51-1.00, p = 0.05, I² = 27.4%). Subgroup analysis revealed that NIV application with helmet was significantly associated with a lower intubation rate than NIV with face mask. NIV did not show a significant reduction in intubation rate compared to HFNC. In conclusion, NIV application in patients with medical illness and AHRF was associated with a lower risk of tracheal intubation compared to COT. NIV with helmet and HFNC are promising strategies to avoid tracheal intubation in this patient population and warrant further studies. NIV application had no effect on mortality.The study protocol was registered in the International Prospective Register of Systematic Reviews (PROSPERO; CRD42018087342).

ERS/ESICM/ESCMID/ALAT guidelines for the management of severe community-acquired pneumonia

BACKGROUND

Severe community-acquired pneumonia (sCAP) is associated with high morbidity and mortality, and while European and non-European guidelines are available for community-acquired pneumonia, there are no specific guidelines for sCAP.

MATERIALS AND METHODOLOGY

The European Respiratory Society (ERS), European Society of Intensive Care Medicine (ESICM), European Society of Clinical Microbiology and Infectious Diseases (ESCMID) and Latin American Thoracic Association (ALAT) launched a task force to develop the first international guidelines for sCAP. The panel comprised a total of 18 European and four non-European experts, as well as two methodologists. Eight clinical questions for sCAP diagnosis and treatment were chosen to be addressed. Systematic literature searches were performed in several databases. Meta-analyses were performed for evidence synthesis, whenever possible. The quality of evidence was assessed with GRADE (Grading of Recommendations, Assessment, Development and Evaluation). Evidence to Decision frameworks were used to decide on the direction and strength of recommendations.

RESULTS

Recommendations issued were related to diagnosis, antibiotics, organ support, biomarkers and co-adjuvant therapy. After considering the confidence in effect estimates, the importance of outcomes studied, desirable and undesirable consequences of treatment, cost, feasibility, acceptability of the intervention and implications to health equity, recommendations were made for or against specific treatment interventions.

CONCLUSIONS

In these international guidelines, ERS, ESICM, ESCMID and ALAT provide evidence-based clinical practice recommendations for diagnosis, empirical treatment and antibiotic therapy for sCAP, following the GRADE approach. Furthermore, current knowledge gaps have been highlighted and recommendations for future research have been made.

High-flow nasal cannula reduces intubation rate in patients with COVID-19 with acute respiratory failure: a meta-analysis and systematic review

OBJECTIVE

This study aimed to investigate the effect of high-flow nasal cannula therapy (HFNC) versus conventional oxygen therapy (COT) on intubation rate, 28-day intensive care unit (ICU) mortality, 28-day ventilator-free days (VFDs) and ICU length of stay (ICU LOS) in adult patients with acute respiratory failure (ARF) associated with COVID-19.

DESIGN

Systematic review and meta-analysis.

DATA SOURCES

PubMed, Web of Science, Cochrane Library and Embase up to June 2022.

ELIGIBILITY CRITERIA FOR SELECTING STUDIES

Only randomised controlled trials or cohort studies comparing HFNC with COT in patients with COVID-19 were included up to June 2022. Studies conducted on children or pregnant women, and those not published in English were excluded.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently screened the titles, abstracts and full texts. Relevant information was extracted and curated in the tables. The Cochrane Collaboration tool and Newcastle-Ottawa Scale were used to assess the quality of randomised controlled trials or cohort studies. Meta-analysis was conducted using RevMan V.5.4 computer software using a random effects model with a 95% CI. Heterogeneity was assessed using Cochran's Q test (χ²) and Higgins I² statistics, with subgroup analyses to account for sources of heterogeneity.

RESULTS

Nine studies involving 3370 (1480 received HFNC) were included. HFNC reduced the intubation rate compared with COT (OR 0.44, 95% CI 0.28 to 0.71, p=0.0007), decreased 28-day ICU mortality (OR 0.54, 95% CI 0.30 to 0.97, p=0.04) and improved 28-day VFDs (mean difference (MD) 2.58, 95% CI 1.70 to 3.45, p<0.00001). However, HFNC had no effect on ICU LOS versus COT (MD 0.52, 95% CI -1.01 to 2.06, p=0.50).

CONCLUSIONS

Our study indicates that HFNC may reduce intubation rate and 28-day ICU mortality, and improve 28-day VFDs in patients with ARF due to COVID-19 compared with COT. Large-scale randomised controlled trials are necessary to validate our findings.

PROSPERO REGISTRATION NUMBER

CRD42022345713.

High flow nasal cannula combined with non-invasive ventilation versus high flow nasal cannula alone in patients with acute hypoxemic respiratory failure due to pneumonia: a randomized controlled trial

In this monocentric, open label, randomized controlled trial we aimed to compare the efficacy of combined High Flow Nasal Cannula (HFNC) and Non invasive Ventilation (NIV) versus HFNC alone in acute hypoxemic respiratory failure (hARF) in patients affected by Community Acquired Pneumonia (CAP). We enrolled 49 patients affected by CAP with moderate to severe hypoxemic respiratory failure (P/F < 300). The patients were randomized into two groups: one has been treated with HFNC alone (group A) while the other received NIV alternated to HFNC every 3 hours (group B). The primary outcome was P/F change from baseline to 21 hours. Secondary outcomes included variation of pH and pCO2, need to continue HFNC or NIV/HFNC after 45 hours, orotracheal intubation, mortality rate, and the devices comfort. Not statistical significant differences between the two arms were shown in the P/F change at 21 hours since baseline, in pCO2 and pH variation, mortality at hospital and at follow-up. We emphasize the importance of combined HFNC with NIV as a first step for severe pneumonia treatment whereas HFNC might represent as the first step treatment in less severe patients and during the NIV intervals.

Introducing helmet non-invasive ventilation during COVID-19 pandemic: Early experience of two centres

Purpose

The helmet is a novel interface for delivering non-invasive ventilation (NIV). We conducted a case series to characterize introduction of the helmet interface in both COVID and non-COVID patients at two-centres.

Methods

We enrolled all patients with respiratory failure admitted to the Juravinski Hospital (Hamilton, Canada) and St. Joseph's Health Center (Syracuse, New York) between November 1, 2020 and June 30, 2021 who used the helmet interface (Intersurgical StarMed) as part of this introduction into clinical practice. We collected patient demographics, reason for respiratory failure, NIV settings, device-related complications and outcomes. We report respiratory therapist's initial experiences with the helmet using descriptive results.

Results

We included 16 patients with a mean age of 64.3 ± 10.9 years. The most common etiology for respiratory failure was pneumonia (81.3%). The median duration of NIV during the ICU admission was 67.5 (15.3, 80.8) hours, with a mean maximum PS of 13.9 ± 6.6 cm H2O and a mean maximum PEEP of 10.4 ± 5.1 cm H20. Three patients (18.7%) did not tolerate the helmet. Ten (62.5%) patients ultimately required intubation, and 7 (43.4%) patients died while in the ICU. The most common reason for intubation was worsening hypoxia (70%). No adverse events related to the helmet were recorded.

Conclusion

Over the 8-month period of this study, we found that the helmet was well tolerated in over 80% of patients, although, more than half ultimately required intubation. Randomized controlled trials with this device are required to fully assess the efficacy of this interface.

Impact of noninvasive ventilation at a municipal emergency department on ICU admissions

BACKGROUND

In 2015, the emergency department of a municipal hospital in Vienna began to perform noninvasive ventilation (NIV) on patients admitted for acute respiratory failure, given no intubation criteria were met. The intention of this study was to show to which type of hospital unit patients were transferred after undergoing NIV in the emergency department. Additionally, the impact of the underlying disease, a patient's sex and age and the year of intervention were analyzed.

METHODS

A single-center retrospective exploratory study was performed on 371 patients. All patients with acute respiratory failure who were noninvasively ventilated at the study center emergency department from 2015 to 2018 were eligible. Relevant data were extracted from the patient's medical records.

RESULTS

A total of 43.7% (95% confidence interval, CI 38.8-48.5%) of patients were successfully stabilized in the emergency department through NIV and subsequently transferred to a normal care unit or discharged. This nonintensive care admission rate was significantly associated with certain underlying medical conditions, age and year of intervention. A further 19.7% (95% CI 15.6-23.7%) of patients were transferred to an intermediate care unit instead of an intensive care unit.

CONCLUSION

These findings emphasize the importance of noninvasive ventilation at the emergency department in reducing load on intensive care units and ensuring an efficient hospital workflow. Nonintensive care admission rate appears to be the highest in patients with pulmonary edema, especially in the higher age range and is also associated with the level of staff training. Prospective trials are needed to accurately confirm these correlations.

Severe community-acquired pneumonia

Severe community-acquired pneumonia is the most life-threatening form of community-acquired pneumonia, characterised by intensive care unit admission and high morbidity and mortality. In this review article, we cover in depth six aspects of severe community-acquired pneumonia that are still controversial: use of PCR molecular techniques for microbial diagnosis; the role of biomarkers for initial management; duration of treatment, macrolides or quinolones in the initial empirical antibiotic therapy; the use of prediction scores for drug-resistant pathogens to modify initial empiric therapy; the use of noninvasive mechanical ventilation and high-flow nasal oxygen; and the use of corticosteroids as adjunctive therapy in severe community-acquired pneumonia.

Supportive Care in Patients with Critical Coronavirus Disease 2019

Specific therapies for the treatment of coronavirus disease 2019 (COVID-19) have limited efficacy in the event a patient worsens clinically and requires admission to the intensive care unit (ICU). Thus, providing quality supportive care is essential to the overall management of patients with critical COVID-19. Patients with respiratory failure not requiring intubation should be supported with noninvasive positive pressure ventilation, continuous positive airway pressure, or high flow oxygenation. Use of these respiratory modalities may prevent patients from subsequently requiring intubation. Basic components of supportive care for the critically ill should be applied equally to patients with COVID-19 in the ICU.

High-flow nasal oxygen in acute hypoxemic respiratory failure: A narrative review of the evidence before and after the COVID-19 pandemic

High-flow nasal oxygen (HFNO) is a type of non-invasive advanced respiratory support that allows the delivery of high-flow and humidified air through a nasal cannula. It can deliver a higher inspired oxygen fraction than conventional oxygen therapy (COT), improves secretion clearance, has a small positive end-expiratory pressure, and exhibits a washout effect on the upper air space that diminishes dead space ventilation. HFNO has been shown to reduce the work of breathing in acute hypoxemic respiratory failure (AHRF) and has become an interesting option for non-invasive respiratory support. Evidence published before the COVID-19 pandemic suggested a possible reduction of the need for invasive mechanical ventilation compared to COT. The COVID-19 pandemic has resulted in a substantial increase in AHRF worldwide, overwhelming both acute and intensive care unit capacity in most countries. This triggered new trials, adding to the body of evidence on HFNO in AHRF and its possible benefits compared to COT or non-invasive ventilation. We have summarized and discussed this recent evidence to inform the best supportive strategy in AHRF both related and unrelated to COVID-19.

Helmet-Noninvasive Ventilation for Hospitalized Critically Ill COVID-19 Patients: Has Vaccination and the New Variants Changed Evidence?

Noninvasive ventilation (NIV) is a technique for breathing support that significantly improves gas exchange and vital signs, reducing intubation and mortality rates. Helmets, unlike facemasks, allow for longer-term treatment and better ventilation, also being more cost-effective. As of today, we have found no reviews addressing this topic. This review aims to identify, map, and describe the characteristics of the use of noninvasive ventilation through helmet interface in critically ill COVID-19 adult patients hospitalized in acute care settings throughout the multiple moments that defined the COVID-19 pandemic. This scoping review will follow the methodology for scoping reviews proposed by JBI. A set of relevant electronic databases will be searched using terms such as COVID-19, helmet, and noninvasive ventilation. Two reviewers will independently perform the study selection regarding their eligibility. Data extraction will be accomplished using a researcher’s developed tool considering the review questions. Findings will be presented in tables and a narrative description that aligns with the review’s objective. This scoping review will consider any quantitative, qualitative, mixed-methods studies and systematic review designs for inclusion, focusing on the use of helmet on critically ill adult patients with COVID-19 hospitalized in acute care settings.

Respiratory support strategy in adults with acute hypoxemic respiratory failure: a systematic review and network meta-analysis

INTRODUCTION

Network meta-analyses (NMAs) of respiratory management strategies for acute hypoxemic respiratory failure (AHRF) have been reported, but no previous study has compared noninvasive ventilation (NIV), high-flow nasal oxygen (HFNO), standard oxygenation therapy (SOT), and invasive mechanical ventilation (IMV) for de novo AHRF. Therefore, we conducted an NMA to assess the effectiveness of these four respiratory strategies in patients with de novo AHRF.

METHODS

The Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, and Ichushi databases were searched. Studies including adults aged ≥18 years with AHRF and RCTs that compared two different oxygenation techniques (SOT, NIV, HFNO, or IMV) were selected. A frequentist-based approach with multivariate random-effects meta-analysis was used. The outcomes were mortality and intubation rates.

RESULTS

Among the 14,263 records initially identified, 25 studies (3302 patients) were included. In the analysis of mortality, compared to SOT, NIV (risk ratio [RR], 0.76; 95% confidence interval [CI], 0.61-0.95) reduced mortality; however, IMV (RR, 1.01; 95% CI, 0.57-1.78) and HFNO (RR, 0.89; 95% CI, 0.66-1.20) did not. For assessments of the intubation incidence, compared to SOT, NIV use (RR, 0.63; 95% CI, 0.51-0.79) was associated with a reduction in intubation, but HFNO (RR, 0.82; 95% CI, 0.61-1.11) was not significant.

CONCLUSIONS

Our NMA demonstrated that only NIV showed clinical benefits compared with SOT as an initial respiratory strategy for de novo AHRF. Further investigation, especially comparison with HFNO, is warranted.

TRIAL REGISTRATION

PROSPERO (registration number: CRD42020213948 , 11/11/2020).

Noninvasive Oxygenation in Patients with Acute Respiratory Failure: Current Perspectives

Purpose of Review

High-flow nasal oxygen and noninvasive ventilation are two alternative strategies to standard oxygen in the management of acute respiratory failure.

Discussion

Although high-flow nasal oxygen has gained major popularity in ICUs due to its simplicity of application, good comfort for patients, efficiency in improving oxygenation and promising results in patients with acute hypoxemic respiratory failure, further large clinical trials are needed to confirm its superiority over standard oxygen. Non-invasive ventilation may have deleterious effects, especially in patients exerting strong inspiratory efforts, and no current recommendations support its use in this setting. Protective non-invasive ventilation using higher levels of positive-end expiratory pressure, more prolonged sessions and other interfaces such as the helmet may have beneficial physiological effects leading to it being proposed as alternative to high-flow nasal oxygen in acute hypoxemic respiratory failure. By contrast, non-invasive ventilation is the first-line strategy of oxygenation in patients with acute exacerbation of chronic lung disease, while high-flow nasal oxygen could be an alternative to non-invasive ventilation after partial reversal of respiratory acidosis. Questions remain about the target populations and non-invasive oxygen strategy representing the best alternative to standard oxygen in acute hypoxemic respiratory failure. As concerns acute on-chronic-respiratory failure, the place of high-flow nasal oxygen remains to be evaluated.

Thoracic Society of Australia and New Zealand Position Statement on Acute Oxygen Use in Adults: 'Swimming between the flags'

Oxygen is a life-saving therapy but, when given inappropriately, may also be hazardous. Therefore, in the acute medical setting, oxygen should only be given as treatment for hypoxaemia and requires appropriate prescription, monitoring and review. This update to the Thoracic Society of Australia and New Zealand (TSANZ) guidance on acute oxygen therapy is a brief and practical resource for all healthcare workers involved with administering oxygen therapy to adults in the acute medical setting. It does not apply to intubated or paediatric patients. Recommendations are made in the following six clinical areas: assessment of hypoxaemia (including use of arterial blood gases); prescription of oxygen; peripheral oxygen saturation targets; delivery, including non-invasive ventilation and humidified high-flow nasal cannulae; the significance of high oxygen requirements; and acute hypercapnic respiratory failure. There are three sections which provide (1) a brief summary, (2) recommendations in detail with practice points and (3) a detailed explanation of the reasoning and evidence behind the recommendations. It is anticipated that these recommendations will be disseminated widely in structured programmes across Australia and New Zealand.

Noninvasive respiratory support for COVID-19 patients: when, for whom, and how?

The significant mortality rate and prolonged ventilator days associated with invasive mechanical ventilation (IMV) in patients with severe COVID-19 have incited a debate surrounding the use of noninvasive respiratory support (NIRS) (i.e., HFNC, CPAP, NIV) as a potential treatment strategy. Central to this debate is the role of NIRS in preventing intubation in patients with mild respiratory disease and the potential beneficial effects on both patient outcome and resource utilization. However, there remains valid concern that use of NIRS may prolong time to intubation and lung protective ventilation in patients with more advanced disease, thereby worsening respiratory mechanics via self-inflicted lung injury. In addition, the risk of aerosolization with the use of NIRS has the potential to increase healthcare worker (HCW) exposure to the virus. We review the existing literature with a focus on rationale, patient selection and outcomes associated with the use of NIRS in COVID-19 and prior pandemics, as well as in patients with acute respiratory failure due to different etiologies (i.e., COPD, cardiogenic pulmonary edema, etc.) to understand the potential role of NIRS in COVID-19 patients. Based on this analysis we suggest an algorithm for NIRS in COVID-19 patients which includes indications and contraindications for use, monitoring recommendations, systems-based practices to reduce HCW exposure, and predictors of NIRS failure. We also discuss future research priorities for addressing unanswered questions regarding NIRS use in COVID-19 with the goal of improving patient outcomes.

Efficacy of non-invasive and invasive respiratory management strategies in adult patients with acute hypoxaemic respiratory failure: a systematic review and network meta-analysis

Background

Although non-invasive respiratory management strategies have been implemented to avoid intubation, patients with de novo acute hypoxaemic respiratory failure (AHRF) are high risk of treatment failure. In the previous meta-analyses, the effect of non-invasive ventilation was not evaluated according to ventilation modes in those patients. Furthermore, no meta-analyses comparing non-invasive respiratory management strategies with invasive mechanical ventilation (IMV) have been reported. We performed a network meta-analysis to compare the efficacy of non-invasive ventilation according to ventilation modes with high-flow nasal oxygen (HFNO), standard oxygen therapy (SOT), and IMV in adult patients with AHRF.

Methods

The Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, and Ichushi databases were searched. Studies including adults with AHRF and randomized controlled trials (RCTs) comparing two different respiratory management strategies (continuous positive airway pressure (CPAP), pressure support ventilation (PSV), HFNO, SOT, or IMV) were reviewed.

Results

We included 25 RCTs (3,302 participants: 27 comparisons). Using SOT as the reference, CPAP (risk ratio [RR] 0.55; 95% confidence interval [CI] 0.31–0.95; very low certainty) was associated significantly with a lower risk of mortality. Compared with SOT, PSV (RR 0.81; 95% CI 0.62–1.06; low certainty) and HFNO (RR 0.90; 95% CI 0.65–1.25; very low certainty) were not associated with a significantly lower risk of mortality. Compared with IMV, no non-invasive respiratory management was associated with a significantly lower risk of mortality, although all certainties of evidence were very low. The probability of being best in reducing short-term mortality among all possible interventions was higher for CPAP, followed by PSV and HFNO; IMV and SOT were tied for the worst (surface under the cumulative ranking curve value: 93.2, 65.0, 44.1, 23.9, and 23.9, respectively).

Conclusions

When performing non-invasive ventilation among patients with de novo AHRF, it is important to avoid excessive tidal volume and lung injury. Although pressure support is needed for some of these patients, it should be applied with caution because this may lead to excessive tidal volume and lung injury.

Trial registration protocols.io (Protocol integer ID 49375, April 23, 2021). 10.17504/protocols.io.buf7ntrn.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-021-03835-8.

Oxygenation strategy during acute respiratory failure in immunocompromised patients

Acute respiratory failure (ARF) in immunocompromised patients remains challenging to treat. A large number of case require admission to intensive care unit (ICU) where mortality remains high. Oxygenation without intubation is important in this setting. This review summarizes recent studies assessing oxygenation devices for immunocompromised patients. Previous studies showed that non-invasive ventilation (NIV) has been associated with lower intubation and mortality rates. Indeed, in recent years, the outcomes of immunocompromised patients admitted to the ICU have improved. In the most recent randomized controlled trials, including immunocompromised patients admitted to the ICU with ARF, neither NIV nor high-flow nasal oxygen (HFNO) could reduce the mortality rate. In this setting, other strategies need to be tested to decrease the mortality rate. Early admission strategy and avoiding late failure of oxygenation strategy have been assessed in retrospective studies. However, objective criteria are still lacking to clearly discriminate time to admission or time to intubation. Also, diagnosis strategy may have an impact on intubation or mortality rates. On the other hand, lack of diagnosis has been associated with a higher mortality rate. In conclusion, improving outcomes in immunocompromised patients with ARF may include strategies other than the oxygenation strategy alone. This review discusses other unresolved questions to decrease mortality after ICU admission in such patients.

Bronchoscopy in intubated and non-intubated intensive care unit patients with respiratory failure

Bronchoscopy is one of the important tool for the pulmonary and critical care physicians to diagnose and treat various pulmonary conditions. It is increasingly being used by the intensivist due to its safety and portability. The utilization of bronchoscopy in the intensive care unit (ICU) has made the diagnosis and treatment of many conditions more feasible to intensivists. Sedation, topical or intravenous, usually helps better tolerate the procedure. However, the risks and benefits of bronchoscopy should be carefully considered in critically ill patients. The hypoxic patients in ICU pose a challenge as hypoxemia is one of the known complications of bronchoscopy, and this risk is exacerbated in patients with hypoxic respiratory failure. Bronchoscopy is relatively contraindicated in patients with severe hypoxemia and coagulopathy. However, bronchoscopy in hypoxic patients can have diagnostic as well as therapeutic implications. In patients with hypoxic respiratory failure, the use of non-invasive ventilation (NIV) during bronchoscopy has been shown to reduce the risk of intubation. On the other hand, bronchoscopy in mechanically ventilated patients is not contraindicated and has been widely used. Staying focused, monitoring vital signs closely, limiting the scope time in the airway, and understanding patient’s physiology may help decrease risk of complications. In this review, we discuss indications, techniques, complications, and yield associated with bronchoscopy in critically ill hypoxic patients.

Characteristics of prolonged noninvasive ventilation in emergency departments and impact upon effectiveness. Analysis of the VNICat registry

OBJECTIVE

To analyze the characteristics and variables associated with prolonged noninvasive ventilation performed completely in Emergency Departments (NIV-ED) and its influence upon effectiveness.

DESIGN

A prospective, multicenter, observational multipurpose cohort study was carried out.

SETTING

VNICAT Registry.

SUBJECTS

Patients in which NIV-ED was performed in 11 Catalan hospitals in the months of February or March 2015.

INTERVENTION

No.

VARIABLES

The study variable was NIV-ED, which as a function of time was defined as prolonged or not prolonged. The efficacy variable was the success of the technique in terms of patient improvement.

RESULTS

A total of 125 patients were included, with a median NIV-ED duration of 12 h, which was the cut-off point for the comparator groups. In 60 cases (48%) NIV-ED was not prolonged (<12 h), while in 65 cases (52%) ventilation was prolonged (≥12 h). Non-prolonged NIV-ED was associated to the indication of acute heart failure and prolonged ventilation to the presence of diabetes. There were no differences between non-prolonged and prolonged NIV-ED in terms of efficacy, and the success rate in terms of improvement was 68.3% and 76.9%, respectively, with an adjusted odds ratio of 1.49 (95%CI 0.61-3.60).

CONCLUSIONS

Prolonged NIV-ED is a frequent situation, but few variables associated to it have been studied. The presence of prolonged ventilation did not influence the success rate of NIV.

The Noninvasive Ventilation Outcomes (NIVO) score: prediction of in-hospital mortality in exacerbations of COPD requiring assisted ventilation

INTRODUCTION

Acute exacerbations of COPD (AECOPD) complicated by acute (acidaemic) hypercapnic respiratory failure (AHRF) requiring ventilation are common. When applied appropriately, ventilation substantially reduces mortality. Despite this, there is evidence of poor practice and prognostic pessimism. A clinical prediction tool could improve decision making regarding ventilation, but none is routinely used.

METHODS

Consecutive patients admitted with AECOPD and AHRF treated with assisted ventilation (principally noninvasive ventilation) were identified in two hospitals serving differing populations. Known and potential prognostic indices were identified a priori. A prediction tool for in-hospital death was derived using multivariable regression analysis. Prospective, external validation was performed in a temporally separate, geographically diverse 10-centre study. The trial methodology adhered to TRIPOD (Transparent Reporting of a Multivariable Prediction Model for Individual Prognosis or Diagnosis) recommendations.

RESULTS

Derivation cohort: n=489, in-hospital mortality 25.4%; validation cohort: n=733, in-hospital mortality 20.1%. Using six simple categorised variables (extended Medical Research Council Dyspnoea score 1-4/5a/5b, time from admission to acidaemia >12 h, pH <7.25, presence of atrial fibrillation, Glasgow coma scale ≤14 and chest radiograph consolidation), a simple scoring system with strong prediction of in-hospital mortality is achieved. The resultant Noninvasive Ventilation Outcomes (NIVO) score had area under the receiver operating curve of 0.79 and offers good calibration and discrimination across stratified risk groups in its validation cohort.

DISCUSSION

The NIVO score outperformed pre-specified comparator scores. It is validated in a generalisable cohort and works despite the heterogeneity inherent to both this patient group and this intervention. Potential applications include informing discussions with patients and their families, aiding treatment escalation decisions, challenging pessimism and comparing risk-adjusted outcomes across centres.

Non-invasive ventilatory support and high-flow nasal oxygen as first-line treatment of acute hypoxemic respiratory failure and ARDS

The role of non-invasive respiratory support (high-flow nasal oxygen and noninvasive ventilation) in the management of acute hypoxemic respiratory failure and acute respiratory distress syndrome is debated. The oxygenation improvement coupled with lung and diaphragm protection produced by non-invasive support may help to avoid endotracheal intubation, which prevents the complications of sedation and invasive mechanical ventilation. However, spontaneous breathing in patients with lung injury carries the risk that vigorous inspiratory effort, combined or not with mechanical increases in inspiratory airway pressure, produces high transpulmonary pressure swings and local lung overstretch. This ultimately results in additional lung damage (patient self-inflicted lung injury), so that patients intubated after a trial of noninvasive support are burdened by increased mortality. Reducing inspiratory effort by high-flow nasal oxygen or delivery of sustained positive end-expiratory pressure through the helmet interface may reduce these risks. In this physiology-to-bedside review, we provide an updated overview about the role of noninvasive respiratory support strategies as early treatment of hypoxemic respiratory failure in the intensive care unit. Noninvasive strategies appear safe and effective in mild-to-moderate hypoxemia (PaO₂/FiO₂ > 150 mmHg), while they can yield delayed intubation with increased mortality in a significant proportion of moderate-to-severe (PaO₂/FiO₂ ≤ 150 mmHg) cases. High-flow nasal oxygen and helmet noninvasive ventilation represent the most promising techniques for first-line treatment of severe patients. However, no conclusive evidence allows to recommend a single approach over the others in case of moderate-to-severe hypoxemia. During any treatment, strict physiological monitoring remains of paramount importance to promptly detect the need for endotracheal intubation and not delay protective ventilation.

[Management of Adult Community-Acquired Pneumonia and Prevention - Update 2021 - Guideline of the German Respiratory Society (DGP), the Paul-Ehrlich-Society for Chemotherapy (PEG), the German Society for Infectious Diseases (DGI), the German Society of Medical Intensive Care and Emergency Medicine (DGIIN), the German Viological Society (DGV), the Competence Network CAPNETZ, the German College of General Practitioneers and Family Physicians (DEGAM), the German Society for Geriatric Medicine (DGG), the German Palliative Society (DGP), the Austrian Society of Pneumology Society (ÖGP), the Austrian Society for Infectious and Tropical Diseases (ÖGIT), the Swiss Respiratory Society (SGP) and the Swiss Society for Infectious Diseases Society (SSI)]

The present guideline provides a new and updated concept of the management of adult patients with community-acquired pneumonia. It replaces the previous guideline dating from 2016.The guideline was worked out and agreed on following the standards of methodology of a S3-guideline. This includes a systematic literature search and grading, a structured discussion of recommendations supported by the literature as well as the declaration and assessment of potential conflicts of interests.The guideline has a focus on specific clinical circumstances, an update on severity assessment, and includes recommendations for an individualized selection of antimicrobial treatment.The recommendations aim at the same time at a structured assessment of risk for adverse outcome as well as an early determination of treatment goals in order to reduce mortality in patients with curative treatment goal and to provide palliation for patients with treatment restrictions.

Risk factors of non-invasive ventilation failure in hematopoietic stem-cell transplantation patients with acute respiratory distress syndrome

Background:

Non-invasive ventilation (NIV) was one of the first-line ventilation supports for hematopoietic stem-cell transplantation (HSCT) patients with acute respiratory distress syndrome (ARDS). Successful NIV may avoid need for intubation. However, the influence NIV failure had on patients’ outcome and its risk factors were hardly known.

Methods:

In this retrospective observational study, we reported risk factors and incidence of NIV failure in HSCT patients who were admitted to the Intensive Care Unit (ICU) with a diagnosis of ARDS and supported with mechanical ventilation, in a 5-year period. Patient outcomes, such as ventilator-free days, ICU-free days, and ICU mortality were also reported.

Results:

Of all the 94 patients included, 70 patients were initially supported with NIV. NIV failure occurred in 44 (63%) patients. Male sex, elevated serum galactomannan (GM) test, (1-3)-β-D-glucan (BG) assay, or elevated serum creatinine level were risk factors for NIV failure. When compared with the NIV success group, failure of NIV was associated with much fewer ICU-free days (22 versus 0, p < 0.001, Cohen’s d = 0.62) and higher ICU mortality (9.5% versus 75.5%, p < 0.001, Pearson’s r = 0.75). There was no difference in ICU-free days, ventilator-free days and ICU mortality between NIV failure and initial invasive mechanical ventilation (IMV) groups. Patients who failed in NIV support had a higher ICU mortality (75.5%) than those who succeeded (9.5%).

Conclusion:

In a small cohort of HSCT patients with mainly moderate severity of ARDS, male patients with elevated serum GM/BG test or serum creatinine level had a higher risk of NIV failure. Both NIV failure and initial IMV groups were characterized by high mortality rate and extremely low ICU-free days and ventilator-free days; failure of NIV support may further aggravate patient prognosis.

The reviews of this paper are available via the supplemental material section.

Post-extubation oxygenation strategies in acute respiratory failure: a systematic review and network meta-analysis

Background

High-flow nasal cannula oxygenation (HFNC) and noninvasive positive-pressure ventilation (NPPV) possibly decrease tracheal reintubation rates better than conventional oxygen therapy (COT); however, few large-scale studies have compared HFNC and NPPV. We conducted a network meta-analysis (NMA) to compare the effectiveness of three post-extubation respiratory support devices (HFNC, NPPV, and COT) in reducing the mortality and reintubation risk.

Methods

The Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, and Ichushi databases were searched. COT, NPPV, and HFNC use were assessed in patients who were aged ≥ 16 years, underwent invasive mechanical ventilation for > 12 h for acute respiratory failure, and were scheduled for extubation after spontaneous breathing trials. The GRADE Working Group Approach was performed using a frequentist-based approach with multivariate random-effect meta-analysis. Short-term mortality and reintubation and post-extubation respiratory failure rates were compared.

Results

After evaluating 4631 records, 15 studies and 2600 patients were included. The main cause of acute hypoxic respiratory failure was pneumonia. Although NPPV/HFNC use did not significantly lower the mortality risk (relative risk [95% confidence interval] 0.75 [0.53–1.06] and 0.92 [0.67–1.27]; low and moderate certainty, respectively), HFNC use significantly lowered the reintubation risk (0.54 [0.32–0.89]; high certainty) compared to COT use. The associations of mortality with NPPV and HFNC use with respect to either outcome did not differ significantly (short-term mortality and reintubation, relative risk [95% confidence interval] 0.81 [0.61–1.08] and 1.02 [0.53–1.97]; moderate and very low certainty, respectively).

Conclusion

NPPV or HFNC use may not reduce the risk of short-term mortality; however, they may reduce the risk of endotracheal reintubation.

Trial registration number and date of registration

PROSPERO (registration number: CRD42020139112, 01/21/2020).

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-021-03550-4.

Noninvasive ventilation and high-flow oxygen therapy for severe community-acquired pneumonia

PURPOSE OF REVIEW

We review the evidence on the use of noninvasive respiratory supports (noninvasive ventilation and high-flow nasal cannula oxygen therapy) in patients with acute respiratory failure because of severe community-acquired pneumonia.

RECENT FINDINGS

Noninvasive ventilation is strongly advised for the treatment of hypercapnic respiratory failure and recent evidence justifies its use in patients with hypoxemic respiratory failure when delivered by helmet. Indeed, such interface allows alveolar recruitment by providing high level of positive end-expiratory pressure, which improves hypoxemia. On the other hand, high-flow nasal cannula oxygen therapy is effective in patients with hypoxemic respiratory failure and some articles support its use in patients with hypercapnia. However, early identification of noninvasive respiratory supports treatment failure is crucial to prevent delayed orotracheal intubation and protective invasive mechanical ventilation.

SUMMARY

Noninvasive ventilation is the first-line therapy in patients with acute hypercapnic respiratory failure because of pneumonia. Although an increasing amount of evidence investigated the application of noninvasive respiratory support to hypoxemic respiratory failure, the optimal ventilatory strategy in this setting is uncertain. Noninvasive mechanical ventilation delivered by helmet and high-flow nasal cannula oxygen therapy appear as promising tools but their role needs to be confirmed by future research.

A scoring system derived from electronic health records to identify patients at high risk for noninvasive ventilation failure

OBJECTIVE

To develop and validate a clinical risk prediction score for noninvasive ventilation (NIV) failure defined as intubation after a trial of NIV in non-surgical patients.

DESIGN

Retrospective cohort study of a multihospital electronic health record database.

PATIENTS

Non-surgical adult patients receiving NIV as the first method of ventilation within two days of hospitalization.

MEASUREMENT

Primary outcome was intubation after a trial of NIV. We used a non-random split of the cohort based on year of admission for model development and validation. We included subjects admitted in years 2010-2014 to develop a risk prediction model and built a parsimonious risk scoring model using multivariable logistic regression. We validated the model in the cohort of subjects hospitalized in 2015 and 2016.

MAIN RESULTS

Of all the 47,749 patients started on NIV, 11.7% were intubated. Compared with NIV success, those who were intubated had worse mortality (25.2% vs. 8.9%). Strongest independent predictors for intubation were organ failure, principal diagnosis group (substance abuse/psychosis, neurological conditions, pneumonia, and sepsis), use of invasive ventilation in the prior year, low body mass index, and tachypnea. The c-statistic was 0.81, 0.80 and 0.81 respectively, in the derivation, validation and full cohorts. We constructed three risk categories of the scoring system built on the full cohort; the median and interquartile range of risk of intubation was: 2.3% [1.9%-2.8%] for low risk group; 9.3% [6.3%-13.5%] for intermediate risk category; and 35.7% [31.0%-45.8%] for high risk category.

CONCLUSIONS

In patients started on NIV, we found that in addition to factors known to be associated with intubation, neurological, substance abuse, or psychiatric diagnoses were highly predictive for intubation. The prognostic score that we have developed may provide quantitative guidance for decision-making in patients who are started on NIV.

Material and Technology: Back to the Future for the Choice of Interface for Non-Invasive Ventilation - A Concise Review

Non-invasive ventilation (NIV) has dramatically changed the treatment of both acute and chronic respiratory failure in the last 2 decades. The success of NIV is correlated to the application of the "best ingredients" of a patient's "tailored recipe," including the appropriate choice of the selected candidate, the ventilator setting, the interface, the expertise of the team, and the education of the caregiver. The choice of the interface is crucial for the success of NIV. Type (oral, nasal, nasal pillows, oronasal, hybrid mask, helmet), size, design, material and headgears may affect the patient's comfort with respect to many aspects, such as air leaks, claustrophobia, skin erythema, eye irritation, skin breakdown, and facial deformity in children. Companies are paying great attention to mask development, in terms of shape, materials, comfort, and leak reduction. Although the continuous development of new products has increased the availability of interfaces and the chance to meet different requirements, in patients necessitating several daily hours of NIV, both in acute and in chronic home setting, the rotational use of different interfaces may remain an excellent strategy to decrease the risk of skin breakdown and to improve patient's tolerance. The aim of the present review was to give the readers a background on mask technology and materials in order to enhance their "knowledge" in making the right choice for the interface to apply during NIV in the different clinical scenarios.

Predictors of NIV Treatment in Patients with COPD Exacerbation Complicated by Respiratory Acidaemia

Non-invasive ventilation (NIV) treatment decisions are poorly understood for patients with COPD exacerbation complicated by acute hypercapnic respiratory failure and respiratory acidaemia (ECOPD-RA). We identified 420 NIV-eligible patients from the DECAF study cohorts admitted with an ECOPD-RA. Using bivariate and multivariate analyses, we examined which indices were associated with clinicians' decisions to start NIV, including whether the presence of pneumonia was a deterrent. Admitting hospital, admission from institutional care, partial pressure of oxygen, cerebrovascular disease, pH, systolic blood pressure and white cell count were all associated with the provision of NIV. Of these indices, only pH was also a predictor of inpatient death. Those not treated with NIV included those with milder acidaemia and higher (and sometimes excessive) oxygen levels, and a frailer population with higher Extended Medical Research Council Dyspnoea scores, presumably deemed not suitable for NIV. Pneumonia was not associated with NIV treatment; 34 of 111 (30.6%) NIV-untreated patients had pneumonia, whilst 107 of 309 (34.6%) NIV-treated patients had pneumonia (p = 0.483). In our study, one in four NIV-eligible patients were not treated with NIV. Clinicians' NIV treatment decisions are not based on those indices most strongly associated with mortality risk. One of the strongest predictors of whether a patient received a life-saving treatment is which hospital they attended. Further research is required to aid in the risk stratification of this patient group which may help standardise and improve care.

Noninvasive Ventilation and High-Flow Nasal Therapy Administration in Chronic Obstructive Pulmonary Disease Exacerbations

Noninvasive ventilation (NIV) is considered to be the standard of care for the management of acute hypercapnic respiratory failure in patients with chronic obstructive pulmonary disease exacerbation. It can be delivered safely in any dedicated setting, from emergency rooms to high dependency or intensive care units and wards. NIV helps improving dyspnea and gas exchange, reduces the need for endotracheal intubation, and morbidity and mortality rates. It is therefore recognized as the gold standard in this condition. High-flow nasal therapy helps improving ventilatory efficiency and reducing the work of breathing in patients with severe chronic obstructive pulmonary disease. Early studies indicate that some patients with acute hypercapnic respiratory failure can be managed with high-flow nasal therapy, but more information is needed before specific recommendations for this therapy can be made. Therefore, high-flow nasal therapy use should be individualized in each particular situation and institution, taking into account resources, and local and personal experience with all respiratory support therapies.

Association of Noninvasive Oxygenation Strategies With All-Cause Mortality in Adults With Acute Hypoxemic Respiratory Failure: A Systematic Review and Meta-analysis

IMPORTANCE

Treatment with noninvasive oxygenation strategies such as noninvasive ventilation and high-flow nasal oxygen may be more effective than standard oxygen therapy alone in patients with acute hypoxemic respiratory failure.

OBJECTIVE

To compare the association of noninvasive oxygenation strategies with mortality and endotracheal intubation in adults with acute hypoxemic respiratory failure.

DATA SOURCES

The following bibliographic databases were searched from inception until April 2020: MEDLINE, Embase, PubMed, Cochrane Central Register of Controlled Trials, CINAHL, Web of Science, and LILACS. No limits were applied to language, publication year, sex, or race.

STUDY SELECTION

Randomized clinical trials enrolling adult participants with acute hypoxemic respiratory failure comparing high-flow nasal oxygen, face mask noninvasive ventilation, helmet noninvasive ventilation, or standard oxygen therapy.

DATA EXTRACTION AND SYNTHESIS

Two reviewers independently extracted individual study data and evaluated studies for risk of bias using the Cochrane Risk of Bias tool. Network meta-analyses using a bayesian framework to derive risk ratios (RRs) and risk differences along with 95% credible intervals (CrIs) were conducted. GRADE methodology was used to rate the certainty in findings.

MAIN OUTCOMES AND MEASURES

The primary outcome was all-cause mortality up to 90 days. A secondary outcome was endotracheal intubation up to 30 days.

RESULTS

Twenty-five randomized clinical trials (3804 participants) were included. Compared with standard oxygen, treatment with helmet noninvasive ventilation (RR, 0.40 [95% CrI, 0.24-0.63]; absolute risk difference, -0.19 [95% CrI, -0.37 to -0.09]; low certainty) and face mask noninvasive ventilation (RR, 0.83 [95% CrI, 0.68-0.99]; absolute risk difference, -0.06 [95% CrI, -0.15 to -0.01]; moderate certainty) were associated with a lower risk of mortality (21 studies [3370 patients]). Helmet noninvasive ventilation (RR, 0.26 [95% CrI, 0.14-0.46]; absolute risk difference, -0.32 [95% CrI, -0.60 to -0.16]; low certainty), face mask noninvasive ventilation (RR, 0.76 [95% CrI, 0.62-0.90]; absolute risk difference, -0.12 [95% CrI, -0.25 to -0.05]; moderate certainty) and high-flow nasal oxygen (RR, 0.76 [95% CrI, 0.55-0.99]; absolute risk difference, -0.11 [95% CrI, -0.27 to -0.01]; moderate certainty) were associated with lower risk of endotracheal intubation (25 studies [3804 patients]). The risk of bias due to lack of blinding for intubation was deemed high.

CONCLUSIONS AND RELEVANCE

In this network meta-analysis of trials of adult patients with acute hypoxemic respiratory failure, treatment with noninvasive oxygenation strategies compared with standard oxygen therapy was associated with lower risk of death. Further research is needed to better understand the relative benefits of each strategy.

Factors for Predicting Noninvasive Ventilation Failure in Elderly Patients with Respiratory Failure

Noninvasive ventilation (NIV) is useful when managing critically ill patients. However, it is not easy to apply to elderly patients, particularly those with pneumonia, due to the possibility of NIV failure and the increased mortality caused by delayed intubation. In this prospective observational study, we explored whether NIV was appropriate for elderly patients with pneumonia, defined factors that independently predicted NIV failure, and built an optimal model for prediction of such failure. We evaluated 78 patients with a median age of 77 years. A low PaCO2 level, a high heart rate, and the presence of pneumonia were statistically significant independent predictors of NIV failure. The predictive power for NIV failure of Model III (pneumonia, PaCO2 level, and heart rate) was better than that of Model I (pneumonia alone). Considering the improvement in parameters, patients with successful NIV exhibited significantly improved heart rates, arterial pH and PaCO2 levels, and patients with NIV failure exhibited a significantly improved PaCO2 level only. In conclusion, NIV is reasonable to apply to elderly patients with pneumonia, but should be done with caution. For the early identification of NIV failure, the heart rate and arterial blood gas parameters should be monitored within 2 h after NIV commencement.

Characteristics of prolonged noninvasive ventilation in emergency departments and impact upon effectiveness. Analysis of the VNICat registry

OBJECTIVE

To analyze the characteristics and variables associated with prolonged noninvasive ventilation performed completely in Emergency Departments (NIV-ED) and its influence upon effectiveness.

DESIGN

A prospective, multicenter, observational multipurpose cohort study was carried out.

SETTING

VNICat Registry.

SUBJECTS

Patients in which NIV-ED was performed in 11 Catalan hospitals in the months of February or March 2015.

INTERVENTION

No.

VARIABLES

The study variable was NIV-ED, which as a function of time was defined as prolonged or not prolonged. The efficacy variable was the success of the technique in terms of patient improvement.

RESULTS

A total of 125 patients were included, with a median NIV-ED duration of 12hours, which was the cut-off point for the comparator groups. In 60 cases (48%) NIV-ED was not prolonged (<12hours), while in 65 cases (52%) ventilation was prolonged (≥12hours). Non-prolonged NIV-ED was associated to the indication of acute heart failure and prolonged ventilation to the presence of diabetes. There were no differences between non-prolonged and prolonged NIV-ED in terms of efficacy, and the success rate in terms of improvement was 68.3% and 76.9%, respectively, with an adjusted odds ratio of 1.49 (95%CI 0.61-3.60).

CONCLUSIONS

Prolonged NIV-ED is a frequent situation, but few variables associated to it have been studied. The presence of prolonged ventilation did not influence the success rate of NIV.

Trends in mechanical ventilation use and mortality over time in patients receiving mechanical ventilation in Spain from 2001 to 2015

BACKGROUND

We examined trends in the incidence of ventilator support with noninvasive ventilation (NIV) or invasive mechanical ventilation (IMV) among patients hospitalized in Spain from 2001 to 2015. We also assessed in-hospital mortality (IHM) after receiving these types of ventilator support.

METHODS

This study was an observational retrospective epidemiological study. Our data source was the Spanish National Hospital Discharge Database.

RESULTS

In total, 1,031,497 patients received ventilator support in Spain over the study period. NIV use increased from 18.8 patients per 100.000 inhabitants in 2001 to 108.7 in 2015. IMV utilization increased significantly from 2001 to 2003 and then decreased from 2003 until 2015. Patients who required NIV had the highest mean Charlson Comorbidity Index (CCI) score. Patients who received IMV had the highest in-hospital mortality. Factors associated with an increased risk for IHM were sex, age, conditions included in the CCI (except for COPD and diabetes), haemodialysis, presence of a peripheral arterial catheter, presence of a central venous catheter, readmission and emergency room admission. Undergoing a surgical procedure was a risk factor only for IMV. IHM decreased significantly from 2001 to 2015 in patients who underwent NIV or IMV.

CONCLUSIONS

We identified an increase in the utilization of NIV over time, whereas use of IMV decreased from 2003 until 2015 after an initial increase from 2001 to 2003. We also found a significant decrease in IHM over time.

The benefits of non-invasive ventilation for Community-Acquired Pneumonia: A meta-analysis

BACKGROUND

There is an observed international increase in NIV application as an alternative to endotracheal intubation in non-COPD patients admitted with community acquired pneumonia despite the lack of strong evidence for its use. The aim of this study is the meta-analysis of data from randomised-controlled trials on the effectiveness of non-invasive ventilation versus standard medical care in adults admitted with severe community-acquired pneumonia.

METHODS

Monthly electronic searches on CENTRAL and MEDLINE were performed between September 2017 and October 2019. Only randomized controlled-trials comparing non-invasive ventilation to standard medical care for the treatment of community-acquired pneumonia in adults were eligible for inclusion. The primary outcomes were the rate of endotracheal intubation (ETI) and the proportion of patients meeting the criteria of ETI as defined by the investigators. Secondary outcomes were the ICU and hospital mortality rate. Study eligibility was independently assessed by two investigators. The risk of bias of included studies was assessed using Cochrane's Risk of bias Tool.

RESULTS

Four RCTs involving a total of 218 participants were eligible for inclusion. Results from the meta-analysis showed that NIV significantly reduced rate of ETI (RR = 0.46, 95% CI [0.26, 0.79]), the proportion of patients that met the criteria for ETI (RR = 0.28, 95% CI[0.16, 0.49]) and ICU mortality rate (RR = 0.3, 95% CI[0.09, 0.93]). No significant effect on hospital mortality rate was found (RR = 0.44, 95% CI [0.05, 3.67]). The authors rated quality of evidence based on GRADE criteria as 'Moderate' for the rate of intubation and proportion of patients meeting ETI criteria outcomes, but quality of evidence for ICU and hospital mortality rate as 'Low'.

CONCLUSIONS

This study provides evidence supporting the use of NIV as potential means of avoiding endotracheal intubation and ICU mortality, in patients with acute respiratory failure due to CAP in the critical care setting. However, there is need for further larger international studies.

Acute respiratory failure in randomized trials of noninvasive respiratory support: A systematic review of definitions, patient characteristics, and criteria for intubation

PURPOSE

To examine the definitions of acute respiratory failure, the characteristics of recruited patients, and the criteria for intubation used in randomized trials.

METHODS

We searched MEDLINE for randomized trials of noninvasive respiratory support modalities in patients with de novo respiratory failure. We included trials from 1995 to 2017 that enrolled 40 or more patients and used intubation as an outcome.

RESULTS

We examined the reports of 53 trials that enrolled 7225 patients. There was wide variation in the use of variables for defining acute respiratory failure. Dyspnea was rarely measured and the increase in breathing effort was poorly defined. The characteristics of patients enrolled in trials changed over time and differed by the cause of respiratory failure. Intubation was poorly characterized. The criteria for intubation had more variables than the criteria for respiratory failure.

CONCLUSIONS

We identified deficiencies in the design and reporting of randomized trials, some of which can be remedied by investigators. We also found that patient characteristics differ by the type of respiratory failure. This knowledge can help clinician identify patients at the right moment to benefit from the tested interventions and investigators in developing criteria for enrollment in future trials.

Use High-Flow Nasal Cannula for Acute Respiratory Failure Patients in the Emergency Department: A Meta-Analysis Study

Objective

To evaluate the efficacy of high-flow nasal cannula (HFNC) therapy compared with conventional oxygen therapy (COT) or noninvasive ventilation (NIV) for the treatment of acute respiratory failure (ARF) in emergency departments (EDs).

Method

We comprehensively searched 3 databases (PubMed, EMBASE, and the Cochrane Library) for articles published from database inception to 12 July 2019. This study included only randomized controlled trials (RCTs) that were conducted in EDs and compared HFNC therapy with COT or NIV. The primary outcome was the intubation rate. The secondary outcomes were the mortality rate, intensive care unit (ICU) admission rate, ED discharge rate, need for escalation, length of ED stay, length of hospital stay, and patient dyspnea and comfort scores.

Result

Five RCTs (n = 775) were included. There was a decreasing trend regarding the application of HFNC therapy and the intubation rate, but the difference was not statistically significant (RR, 0.53; 95% CI, 0.26–1.09; p=0.08; I² = 0%). We found that compared with patients who underwent COT, those who underwent HFNC therapy had a reduced need for escalation (RR, 0.41; 95% CI, 0.22–0.78; p=0.006; I² = 0%), reduced dyspnea scores (MD −0.82, 95% CI −1.45 to −0.18), and improved comfort (SMD −0.76 SD, 95% CI −1.01 to −0.51). Compared with the COT group, the HFNC therapy group had a similar mortality rate (RR, 1.25; 95% CI, 0.79–1.99; p=0.34; I² = 0%), ICU admission rate (RR, 1.11; 95% CI, 0.58–2.12; p=0.76; I² = 0%), ED discharge rate (RR, 1.04; 95% CI, 0.63–1.72; p=0.87; I² = 0%), length of ED stay (MD 1.66, 95% CI −0.95 to 4.27), and hospital stay (MD 0.9, 95% CI −2.06 to 3.87).

Conclusion

Administering HFNC therapy in ARF patients in EDs might decrease the intubation rate compared with COT. In addition, it can decrease the need for escalation, decrease the patient's dyspnea level, and increase the patient's comfort level compared with COT.

Noninvasive ventilation as acute therapy

PURPOSE OF REVIEW

Noninvasive ventilation (NIV) is widely used in ICU patients to treat or to prevent acute respiratory failure. Whereas its physiological effects are clearly beneficial in hypercapnic patients, it could be deleterious in hypoxemic patients without hypercapnia.

RECENT FINDINGS

NIV should be cautiously used in patients with de-novo respiratory failure, the vast majority of whom meet the criteria for acute respiratory distress syndrome. Spontaneous breathing with high tidal volumes may worsen lung injury in these patients, and recent findings suggest that NIV may increase the risk of mortality. Even though high-flow oxygen therapy is increasingly applied in this context, NIV remains recommended for management of immunocompromised patients with acute respiratory failure. NIV should be the first-line oxygenation strategy in patients with acute hypercapnic respiratory failure when pH is equal to or below 7.35. Prophylactic NIV prevents respiratory failure after extubation of patients at high risk of reintubation.

SUMMARY

Most previous studies have compared NIV with standard oxygen, and recent recommendations have been established from these findings. Given the growing use of high-flow oxygen therapy, new studies are needed to compare NIV versus high-flow oxygen therapy so as to better define the appropriate indications for each treatment.

Is immunosuppression status a risk factor for noninvasive ventilation failure in patients with acute hypoxemic respiratory failure? A post hoc matched analysis

Background

Recent European/American guidelines recommend noninvasive ventilation (NIV) as a first-line therapy to manage acute hypoxemic respiratory failure in immunocompromised patients. By contrast, NIV may have deleterious effects in nonimmunocompromised patients and experts have been unable to offer a recommendation. Immunocompromised patients have particularly high mortality rates when they require intubation. However, it is not clear whether immunosuppression status is a risk factor for NIV failure. We assessed the impact of immunosuppression status on NIV failure in a post hoc analysis pooling two studies including patients with de novo acute hypoxemic respiratory failure treated with NIV. Patients with hypercapnia, acute exacerbation of chronic lung disease, cardiogenic pulmonary edema, or with do-not-intubate order were excluded.

Results

Among the 208 patients included in the analysis, 71 (34%) were immunocompromised. They had higher severity scores upon ICU admission, higher pressure-support levels, and minute ventilation under NIV, and were more likely to have bilateral lung infiltrates than nonimmunocompromised patients. Intubation and in-ICU mortality rates were higher in immunocompromised than in nonimmunocompromised patients: 61% vs. 43% (p = 0.02) and 38% vs. 15% (p < 0.001), respectively. After adjustment or using a propensity score-matched analysis, immunosuppression was not associated with intubation, whereas it remained independently associated with ICU mortality with an adjusted odds ratio of 2.64 (95% CI 1.24–5.67, p = 0.01).

Conclusions

Immunosuppression status may directly influence mortality but does not seem to be associated with an increased risk of intubation in patients with de novo acute hypoxemic respiratory failure treated with NIV. Studies in this specific population are needed.

Electronic supplementary material

The online version of this article (10.1186/s13613-019-0566-z) contains supplementary material, which is available to authorized users.

Noninvasive ventilation versus oxygen therapy in patients with acute respiratory failure

PURPOSE OF REVIEW

High-flow nasal cannula oxygen therapy (HFOT) is becoming an alternative to noninvasive ventilation (NIV) and standard oxygen in management of patients with acute respiratory failure.

RECENT FINDINGS

Patients with de novo acute respiratory failure should be managed with HFOT rather than NIV. Indeed, the vast majority of patients with de novo respiratory failure meet the criteria for ARDS, and NIV does not seem protective, as patients generate overly high tidal volume that may worsen underlying lung injury. However, NIV remains the first-line oxygenation strategy in postoperative patients and those with acute hypercapnic respiratory failure when pH is equal to or below 7.35. During preoxygenation, NIV also seems to be more efficient than standard oxygen using valve-bag mask to prevent profound oxygen desaturation. In postoperative cardiothoracic patients, HFOT could be an alternative to NIV in the management of acute respiratory failure.

SUMMARY

Recent recommendations for managing patients with acute respiratory failure have been established on the basis of studies comparing NIV with standard oxygen. Growing use of HFOT will lead to new studies comparing NIV versus HFOT in view of more precisely defining the appropriate indications for each treatment.