Noninvasive Ventilation and Survival in Acute Care Settings

The Impact of Delayed Transition From Noninvasive to Invasive Mechanical Ventilation on Hospital Mortality in Immunocompromised Patients With Sepsis

OBJECTIVE

To determine whether mortality differed between initial invasive mechanical ventilation (IMV) or noninvasive ventilation (NIV) followed by delayed IMV in immunocompromised patients with sepsis.

DESIGN

Retrospective analysis using the National Data Center for Medical Service claims data in China from 2017 to 2019.

SETTING

A total of 3530 hospitals across China.

PATIENTS

A total of 36,187 adult immunocompromised patients with sepsis requiring ventilation.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

The primary outcome was hospital mortality. Patients were categorized into NIV initiation or IMV initiation groups based on first ventilation. NIV patients were further divided by time to IMV transition: no transition, immediate (≤ 1 d), early (2-3 d), delayed (4-7 d), or late (≥ 8 d). Mortality was compared between groups using weighted Cox models. Over the median 9-day follow-up, mortality was similar for initial NIV versus IMV (adjusted hazard ratio [HR] 1.006; 95% CI, 0.959-1.055). However, among NIV patients, a longer time to IMV transition is associated with stepwise increases in mortality, from immediate transition (HR 1.65) to late transition (HR 2.51), compared with initial IMV. This dose-response relationship persisted across subgroups and sensitivity analyses.

CONCLUSIONS

Prolonged NIV trial before delayed IMV transition is associated with higher mortality in immunocompromised sepsis patients ultimately intubated.

What Do We Know about Peripartum Cardiomyopathy? Yesterday, Today, Tomorrow

Peripartum cardiomyopathy is a disease that occurs during or after pregnancy and leads to a significant decline in cardiac function in previously healthy women. Peripartum cardiomyopathy has a varying prevalence among women depending on the part of the world where they live, but it is associated with a significant mortality and morbidity in this population. Therefore, timely diagnosis, treatment, and monitoring of this disease from its onset are of utmost importance. Although many risk factors are associated with the occurrence of peripartum cardiomyopathy, such as conditions of life, age of the woman, nutrient deficiencies, or multiple pregnancies, the exact cause of its onset remains unknown. Advances in research on the genetic associations with cardiomyopathies have provided a wealth of data indicating a possible association with peripartum cardiomyopathy, but due to numerous mutations and data inconsistencies, the exact connection remains unclear. Significant insights into the pathophysiological mechanisms underlying peripartum cardiomyopathy have been provided by the theory of an abnormal 16-kDa prolactin, which may be generated in an oxidative stress environment and lead to vascular and consequently myocardial damage. Recent studies supporting this disease mechanism also include research on the efficacy of bromocriptine (a prolactin synthesis inhibitor) in restoring cardiac function in affected patients. Despite significant progress in the research of this disease, there are still insufficient data on the safety of use of certain drugs treating heart failure during pregnancy and breastfeeding. Considering the metabolic changes that occur in different stages of pregnancy and the postpartum period, determining the correct dosing regimen of medications is of utmost importance not only for better treatment and survival of mothers but also for reducing the risk of toxic effects on the fetus.

Non-invasive ventilation in the care of patients with chronic obstructive pulmonary disease with palliative care needs: a scoping review

BACKGROUND

Patients with severe chronic obstructive pulmonary disease (COPD) could have palliative care (PC) needs because of unmet needs such as dyspnoea. This may lead to anxiety and may have an impact on patients' ability to perform daily activities of living. PC can be started when patients with COPD have unmet needs and can be provided alongside disease-modifying therapies. Non-invasive ventilation (NIV) could be an important measure to manage dyspnoea in patients with COPD in need of PC. A scoping review was conducted to gain an overview of the existing research and to identify knowledge gaps. The aim of this scoping review was to systematically map published studies on the use of NIV in patients with COPD with PC needs, including the perspectives and experiences of patients, families, and healthcare professionals (HCPs).

METHODS

This review was conducted following the framework of Arksey and O'Malley. The reporting of the review was guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews checklist. The review protocol was published. AMED, CINAHL, Embase, MEDLINE, PEDro, and PsycInfo were searched from inception to November 14, 2022. The included studies had to report the perspectives and experiences of COPD patients, relatives, and HCPs regarding NIV in the care of patients with COPD with PC needs. In pairs, the authors independently assessed studies' eligibility and extracted data. The data were organised thematically. The results were discussed in a consultation exercise.

RESULTS

This review included 33 papers from 32 studies. Four thematic groupings were identified: preferences and attitudes towards the use of NIV; patient participation in the decision-making process of NIV treatment; conflicting results on the perceived benefits and burdens of treatment; and heterogenous clinical outcomes in experimental studies. Patients perceived NIV as a 'life buoy' to keep them alive. Many patients wanted to take part in the decision-making process regarding NIV treatment but expressed varying degrees of inclusion by HCPs in such decision-making. Conflicting findings were identified regarding the perceived benefits and burdens of NIV treatment. Diversity in heterogeneous clinical outcomes were reported in experimental studies.

CONCLUSIONS

There is a need for more studies designed to investigate the effectiveness of NIV as a palliative measure for patients with COPD with PC needs using comprehensive outcomes. It is especially important to gain more knowledge on the experiences of all stakeholders in the use of home-based NIV treatment to these patients.

Feasibility, safety and efficacy of COVID-19 severe acute respiratory distress syndrome management without invasive mechanical ventilation

BACKGROUND

COVID-19 acute respiratory distress syndrome (ARDS) is often managed with mechanical ventilation (MV), requiring sedation and paralysis, with associated risk of complications. There is limited evidence on the use of high flow nasal cannula (HFNC). We hypothesized that management of COVID-19 ARDS without MV is feasible.

METHODS

Included were all adult patients diagnosed with COVID-19 ARDS, with PaO2/FiO2 ratio <100 at admission, and whose management was initially performed without MV. We evaluated need for intubation during ICU stay, mortality and hospital/ICU length of stay (LOS).

RESULTS

Out of 118 patients, 41 were managed only with HFNC from hospital admission (and at least during first 24 hours in ICU) and had a PaO2/FiO2 ratio <100 (72.9±13.0). Twenty-nine out of 41 patients never required MV: 24 of them survived and were discharged home. Their median ICU LOS was 11 (7-17) days, and their hospital LOS was 29 (18-45) days. We identified PaO2/FiO2 ratio at ICU admission as the only significant predictor for need for MV during ICU stay. We also identified age, length of non-invasive respiratory support before ICU admission, mean value of PaO2/FiO2 ratio during first half and whole ICU stay as predictors of mortality.

CONCLUSIONS

It is safe to monitor in ICU and use HFNC in patients affected by COVID-19 ARDS who initially present data suggesting an early need for intubation. The 41 patients admitted with a PaO2/FiO2 ratio <100 and initially treated only with HFNC show a 22% mortality that is in the lower range of what is reported in recent literature.

Perioperative Pulmonary Complications in the Elderly: The Forgotten System

With a rapidly aging population and increasing global surgical volumes, managing the elevated risk of perioperative pulmonary complications has become an expanding focus for quality improvement in health care. In this narrative review, we will analyze the evidence-based literature to provide high-quality and actionable management strategies to better detect, stratify risk, optimize, and manage perioperative pulmonary complications in geriatric populations.

Personalized Respiratory Support in ARDS: A Physiology-to-Bedside Review

Acute respiratory distress syndrome (ARDS) is a leading cause of disability and mortality worldwide, and while no specific etiologic interventions have been shown to improve outcomes, noninvasive and invasive respiratory support strategies are life-saving interventions that allow time for lung recovery. However, the inappropriate management of these strategies, which neglects the unique features of respiratory, lung, and chest wall mechanics may result in disease progression, such as patient self-inflicted lung injury during spontaneous breathing or by ventilator-induced lung injury during invasive mechanical ventilation. ARDS characteristics are highly heterogeneous; therefore, a physiology-based approach is strongly advocated to titrate the delivery and management of respiratory support strategies to match patient characteristics and needs to limit ARDS progression. Several tools have been implemented in clinical practice to aid the clinician in identifying the ARDS sub-phenotypes based on physiological peculiarities (inspiratory effort, respiratory mechanics, and recruitability), thus allowing for the appropriate application of personalized supportive care. In this narrative review, we provide an overview of noninvasive and invasive respiratory support strategies, as well as discuss how identifying ARDS sub-phenotypes in daily practice can help clinicians to deliver personalized respiratory support and potentially improve patient outcomes.

Noninvasive Ventilation for Acute Respiratory Failure in Pediatric Patients: A Systematic Review and Meta-Analysis

OBJECTIVE

To perform a systematic review and meta-analysis of randomized controlled trials (RCTs) on the use of noninvasive ventilation (NIV) for acute respiratory failure (ARF) in pediatric patients.

DATA SOURCES

We searched PubMed, EMBASE, the Cochrane Central Register of Clinical Trials, and Clinicaltrials.gov with a last update on July 31, 2022.

STUDY SELECTION

We included RCTs comparing NIV with any comparator (standard oxygen therapy and high-flow nasal cannula [HFNC]) in pediatric patients with ARF. We excluded studies performed on neonates and on chronic respiratory failure patients.

DATA EXTRACTION

Baseline characteristics, intubation rate, mortality, and hospital and ICU length of stays were extracted by trained investigators.

DATA SYNTHESIS

We identified 15 RCTs (2,679 patients) for the final analyses. The intubation rate was 109 of 945 (11.5%) in the NIV group, and 158 of 1,086 (14.5%) in the control group (risk ratio, 0.791; 95% CI, 0.629-0.996; p = 0.046; I2 = 0%; number needed to treat = 31). Findings were strengthened after removing studies with intervention duration shorter than an hour and after excluding studies with cross-over as rescue treatment. There was no difference in mortality, and ICU and hospital length of stays.

CONCLUSIONS

In pediatric patients, NIV applied for ARF might reduce the intubation rate compared with standard oxygen therapy or HFNC. No difference in mortality was observed.

Dexmedetomidine as Conduit for Non-Invasive Ventilation (NIV) Compliance in COVID-19 and Chronic Obstructive Pulmonary Disease (COPD) Patients in Intensive Care Unit (ICU) Setting: Case Series

Non-compliance to the non-invasive ventilation (NIV) mask in a distressed hypoxemic patient is not an unusual finding, especially in desaturated coronavirus disease (COVID-19) or chronic obstructive pulmonary disease (COPD) patients with respiratory distress who require ventilatory support to improve oxygenation. Failure to achieve success with the non-invasive ventilatory support with the tight-fitting mask led to emergent endotracheal intubation. This was in view to avert consequences such as severe hypoxemia and subsequent cardiac arrest.  Sedation is an important component of ICU management for noninvasive mechanical ventilation to improve NIV compliance/tolerance. Including the various sedatives used, such as fentanyl, propofol, or midazolam, the most suitable agent to be used as a primary/sole sedative still remains unclear. Dexmedetomidine providing analgosedation without significant respiratory depression facilitates better tolerance of NIV mask application. This case series is a retrospective analysis of patients in whom dexmedetomidine bolus followed by infusion was observed to facilitate compliance to NIV with the tight-fitting mask. Herein, a case summary of six patients with acute respiratory distress who were dyspnoic, agitated have severe hypoxemia were put on NIV with dexmedetomidine infusion is being reported. They were extremely uncooperative as their RASS score (Richmond Agitation-Sedation score) was + 1 to +3, not allowing the application of the NIV mask. Due to their poor compliance with to use of the NIV mask, proper ventilation could not be achieved. Dexmedetomidine infusion (0.3 to 0.4 mcg/kg/hr) was used after a bolus dose (0.2-0.3 mcg/kg). The RASS Score of our patients was +2 or +3 before this intervention which became -1 or -2 after including dexmedetomidine in the treatment protocol. The low dose dexmedetomidine bolus and infusion thereafter showed to improve the patient's acceptance of the device. Oxygen therapy with this was shown to improve patient oxygenation by allowing the acceptance of the tight-fitting NIV face mask. In conclusion, this case series serves as evidence of the use of dexmedetomidine as an effective therapy to calm the agitated desaturated patient, thereby facilitating non-invasive ventilation in COVID-19 and COPD patients and promoting better oxygenation. This may, in turn, avoid endotracheal intubation for invasive ventilation and the associated complications.

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.

[The perioperative role of high-flow cannula oxygen (HFNO)]

High-flow nasal cannula oxygen (HFNO) is commonly used during the perioperative period. Its numerous physiological benefits, satisfactory tolerance and ease of use have led to its widespread application in intensive care and post-anesthesia care units. HFNO is also used in the operating theater in multiple indications: as oxygen supplementation (associated with pressurization) prior to orotracheal intubation; in digestive and bronchial endoscopies, especially in patients at risk of hypoxemia; and in intraoperative surgery requiring spontaneous ventilation (ENT, thoracic surgery…). During the postoperative period, HFNO can be used in a curative strategy for respiratory failure or in a prophylactic strategy to prevent reintubation. In a curative approach, HFNO seems of interest following cardiac or thoracic surgery but has not been evaluated in respiratory failure subsequent to abdominal surgery, in which case noninvasive ventilation remains the gold standard. The risk of respiratory complications depends on type of surgery and on patient comorbidities. As prophylaxis, HFNO is currently preferred to conventional oxygen therapy after cardiac or thoracic surgery, especially in patients at high risk of respiratory complications. For the clinician, it is important to acknowledge the limits of HFNO and to closely monitor patients receiving HFNO, the objective being to avoid delays in intubation that could lead to increased mortality.

Non-invasive ventilation for acute hypoxemic respiratory failure, including COVID-19

Optimal initial non-invasive management of acute hypoxemic respiratory failure (AHRF), of both coronavirus disease 2019 (COVID-19) and non-COVID-19 etiologies, has been the subject of significant discussion. Avoidance of endotracheal intubation reduces related complications, but maintenance of spontaneous breathing with intense respiratory effort may increase risks of patients' self-inflicted lung injury, leading to delayed intubation and worse clinical outcomes. High-flow nasal oxygen is currently recommended as the optimal strategy for AHRF management for its simplicity and beneficial physiological effects. Non-invasive ventilation (NIV), delivered as either pressure support or continuous positive airway pressure via interfaces like face masks and helmets, can improve oxygenation and may be associated with reduced endotracheal intubation rates. However, treatment failure is common and associated with poor outcomes. Expertise and knowledge of the specific features of each interface are necessary to fully exploit their potential benefits and minimize risks. Strict clinical and physiological monitoring is necessary during any treatment to avoid delays in endotracheal intubation and protective ventilation. In this narrative review, we analyze the physiological benefits and risks of spontaneous breathing in AHRF, and the characteristics of tools for delivering NIV. The goal herein is to provide a contemporary, evidence-based overview of this highly relevant topic.

Factors and Outcomes Associated with Failed Noninvasive Positive Pressure Ventilation in Patients with Acute Respiratory Failure

Background

The decision guild for non-invasive positive pressure ventilation (NPPV) application in acute respiratory failure (ARF) patients still needs to work out.

Methods

Adult patients with acute hypoxemic or hypercapnic respiratory failure were recruited and treated with NPPV or primary invasive mechanical ventilation (IMV). Patients’ characteristic and clinical outcomes were recorded. Logistic regression models were used to estimate the adjusted odds ratio (aOR) and 95% confidence intervals for baseline characteristics and clinical outcomes. Subgroup analyses by reason behind successful NPPV were conducted to ascertain if any difference could influence the outcome.

Results

A total of 4525 ARF patients were recruited in our facility between year 2015 and 2017. After exclusion, 844 IMV patients, 66 patients with failed NPPV, and 74 patients with successful NPPV were enrolled. Statistical analysis showed APACHE II score (aOR = 0.93), time between admission and start NPPV (aOR = 0.92), and P/F ratio (aOR = 1.04) were associated with successful NPPV. When comparing with IMV patients, failed NPPV patients displayed a significantly lower APACHE II score, higher Glasgow Coma Scale, longer length of stay in hospital, longer duration of invasive ventilation, RCW/Home ventilator, and some comorbidities.

Conclusion

APACHE II score, time between admission and start NPPV, and PaO2 can be predictors for successful NPPV. The decision of NPPV application is critical as ARF patients with failed NPPV have various worse outcomes than patients receiving primary IMV.

Non-Invasive Ventilation in the Prehospital Emergency Setting: A Systematic Review and Meta-Analysis

INTRODUCTION

Noninvasive ventilation is a well-established treatment for acute respiratory failure, being increasingly applied in the prehospital setting. This systematic review and meta-analysis aims to investigate whether early prehospital initiation of noninvasive ventilation reduces mortality compared to standard oxygen therapy.

METHODS

We searched PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials from inception to February 7^th, 2022, for studies comparing prehospital noninvasive ventilation performed by emergency medical services versus standard oxygen therapy in patients with acute respiratory failure. The primary outcome was mortality at the longest follow-up available.

RESULTS

We included ten randomized studies and two quasi-randomized studies for a total of 1485 patients. Prehospital treatment with noninvasive ventilation compared with standard oxygen therapy did not significantly reduce mortality at the longest follow-up available (107/810 [13%] vs 114/772 [15%]; RR = 0.89; 95% CI, 0.70-1.13; P = 0.34; I²=24%). The endotracheal intubation rate was reduced when receiving prehospital noninvasive ventilation (38/776 [4.9%] vs 81/743 [11%]; RR = 0.44; 95% CI, 0.31-0.63; P < 0.001; I²=0%; number needed to treat 17). The intensive care admission rate (114/532 [21%] vs 129/507 [25%]; RR = 0.85; 95% CI, 0.69-1.04; P = 0.11; I²=0%) and length of hospital stay (mean difference=-1.29 days; 95% CI, -3.35-0.77; P = 0.21; I²=82%) were similar between groups.

CONCLUSIONS

Adults with acute respiratory failure treated in the prehospital setting with noninvasive ventilation had a lower risk of intubation than those managed with standard oxygen therapy, with similar risk of death, intensive care admission, and length of hospital stay.

REVIEW REGISTRATION

PROSPERO CRD42021284947.

SIMEU position paper on non-invasive respiratory support in COVID-19 pneumonia

The rapid worldwide spread of the Coronavirus disease (COVID-19) crisis has put health systems under pressure to a level never experienced before, putting intensive care units in a position to fail to meet an exponentially growing demand. The main clinical feature of the disease is a progressive arterial hypoxemia which rapidly leads to ARDS which makes the use of intensive care and mechanical ventilation almost inevitable. The difficulty of health systems to guarantee a corresponding supply of resources in intensive care, together with the uncertain results reported in the literature with respect to patients who undergo early conventional ventilation, make the search for alternative methods of oxygenation and ventilation and potentially preventive of the need for tracheal intubation, such as non-invasive respiratory support techniques particularly valuable. In this context, the Emergency Department, located between the area outside the hospital and hospital ward and ICU, assumes the role of a crucial junction, due to the possibility of applying these techniques at a sufficiently early stage and being able to rapidly evaluate their effectiveness. This position paper describes the indications for the use of non-invasive respiratory support techniques in respiratory failure secondary to COVID-19-related pneumonia, formulated by the Non-invasive Ventilation Faculty of the Italian Society of Emergency Medicine (SIMEU) on the base of what is available in the literature and on the authors' direct experience. Rationale, literature, tips & tricks, resources, risks and expected results, and patient interaction will be discussed for each one of the escalating non-invasive respiratory techniques: standard oxygen, HFNCO, CPAP, NIPPV, and awake self-repositioning. The final chapter describes our suggested approach to the failing patient.

Non-Invasive Ventilation as a Therapy Option for Acute Exacerbations of Chronic Obstructive Pulmonary Disease and Acute Cardiopulmonary Oedema in Emergency Medical Services

In this observational prospective multicenter study conducted between October 2016 and October 2018, we tested the hypothesis that the use of prehospital non-invasive ventilation (phNIV) to treat patients with acute respiratory insufficiency (ARI) caused by severe acute exacerbations of chronic obstructive pulmonary disease (AECOPD) and acute cardiopulmonary oedema (ACPE) is effective, time-efficient and safe. The data were collected at four different physician response units and three admitting hospitals in a German EMS system. Patients with respiratory failure due to acute exacerbation of chronic obstructive pulmonary disease and acute cardiopulmonary oedema were enrolled. A total of 545 patients were eligible for the final analysis. Patients were treated with oxygen supplementation, non-invasive ventilation or invasive mechanical ventilation. The primary outcomes were defined as changes in the clinical parameters and the in-hospital course. The secondary outcomes included time efficiency, peri-interventional complications, treatment failure rate, and side-effects. Oxygenation under phNIV improved equally to endotracheal intubation (ETI), and more effectively in comparison to standard oxygen therapy (SOT) (paO2 SOT vs. non-invasive ventilation (NIV) vs. ETI: 82 mmHg vs. 125 mmHg vs. 135 mmHg, p-value SOT vs. NIV < 0.0001). In a matched subgroup analysis phNIV was accompanied by a reduced time of mechanical ventilation (phNIV: 1.8 d vs. ETI: 4.2 d) and a shortened length of stay at the intensive care unit (3.4 d vs. 5.8 d). The data support the hypothesis that the treatment of severe AECOPD/ACPE-induced ARI using prehospital NIV is effective, time efficient and safe. Compared to ETI, a matched comparison supports the hypothesis that prehospital implementation of NIV may provide benefits for an in-hospital course.

Comfort During Non-invasive Ventilation

Non-invasive ventilation (NIV) has been shown to be effective in avoiding intubation and improving survival in patients with acute hypoxemic respiratory failure (ARF) when compared to conventional oxygen therapy. However, NIV is associated with high failure rates due, in most cases, to patient discomfort. Therefore, increasing attention has been paid to all those interventions aimed at enhancing patient's tolerance to NIV. Several practical aspects have been considered to improve patient adaptation. In particular, the choice of the interface and the ventilatory setting adopted for NIV play a key role in the success of respiratory assistance. Among the different NIV interfaces, tolerance is poorest for the nasal and oronasal masks, while helmet appears to be better tolerated, resulting in longer use and lower NIV failure rates. The choice of fixing system also significantly affects patient comfort due to pain and possible pressure ulcers related to the device. The ventilatory setting adopted for NIV is associated with varying degrees of patient comfort: patients are more comfortable with pressure-support ventilation (PSV) than controlled ventilation. Furthermore, the use of electrical activity of the diaphragm (EADi)-driven ventilation has been demonstrated to improve patient comfort when compared to PSV, while reducing neural drive and effort. If non-pharmacological remedies fail, sedation can be employed to improve patient's tolerance to NIV. Sedation facilitates ventilation, reduces anxiety, promotes sleep, and modulates physiological responses to stress. Judicious use of sedation may be an option to increase the chances of success in some patients at risk for intubation because of NIV intolerance consequent to pain, discomfort, claustrophobia, or agitation. During the Coronavirus Disease-19 (COVID-19) pandemic, NIV has been extensively employed to face off the massive request for ventilatory assistance. Prone positioning in non-intubated awake COVID-19 patients may improve oxygenation, reduce work of breathing, and, possibly, prevent intubation. Despite these advantages, maintaining prone position can be particularly challenging because poor comfort has been described as the main cause of prone position discontinuation. In conclusion, comfort is one of the major determinants of NIV success. All the strategies aimed to increase comfort during NIV should be pursued.

Evidence-Based Mechanical Ventilatory Strategies in ARDS

Acute respiratory distress syndrome (ARDS) remains one of the leading causes of morbidity and mortality in critically ill patients despite advancements in the field. Mechanical ventilatory strategies are a vital component of ARDS management to prevent secondary lung injury and improve patient outcomes. Multiple strategies including utilization of low tidal volumes, targeting low plateau pressures to minimize barotrauma, using low FiO₂ (fraction of inspired oxygen) to prevent injury related to oxygen free radicals, optimization of positive end expiratory pressure (PEEP) to maintain or improve lung recruitment, and utilization of prone ventilation have been shown to decrease morbidity and mortality. The role of other mechanical ventilatory strategies like non-invasive ventilation, recruitment maneuvers, esophageal pressure monitoring, determination of optimal PEEP, and appropriate patient selection for extracorporeal support is not clear. In this article, we review evidence-based mechanical ventilatory strategies and ventilatory adjuncts for ARDS.

Helmet NIV in Acute Hypoxemic Respiratory Failure due to COVID-19: Change in PaO2/FiO2 Ratio a Predictor of Success

In acute respiratory failure due to severe coronavirus disease 2019 (COVID-19) pneumonia, mechanical ventilation remains challenging and may result in high mortality. The use of noninvasive ventilation (NIV) may delay required invasive ventilation, increase adverse outcomes, and have a potential aerosol risk to caregivers. Data of 30 patients were collected from patient files and analyzed. Twenty-one (70%) patients were weaned successfully after helmet-NIV support (NIV success group), and invasive mechanical ventilation was required in 9 (30%) patients (NIV failure group) of which 8 (26.7%) patients died. In NIV success vs failure patients, the mean baseline PaO₂/FiO₂ ratio (PFR) (147.2 ± 57.9 vs 156.8 ± 59.0 mm Hg; p = 0.683) and PFR before initiation of helmet (132.3 ± 46.9 vs 121.6 ± 32.7 mm Hg; p = 0.541) were comparable. The NIV success group demonstrated a progressive improvement in PFR in comparison with the failure group at 2 hours (158.8 ± 56.1 vs 118.7 ± 40.7 mm Hg; p = 0.063) and 24 hours (PFR-24) (204.4 ± 94.3 vs 121.3 ± 32.6; p = 0.016). As predictor variables, PFR-24 and change (delta) in PFR at 24 hours from baseline or helmet initiation (dPFR-24) were significantly associated with NIV success in univariate analysis but similar significance could not be reflected in multivariate analysis perhaps due to a small sample size of the study. The PFR-24 cutoff of 161 mm Hg and dPFR-24 cutoff of -1.44 mm Hg discriminate NIV success and failure groups with the area under curve (confidence interval) of 0.78 (0.62-0.95); p = 0.015 and 0.74 (0.55-0.93); p = 0.039, respectively. Helmet interface NIV may be a safe and effective tool for the management of patients with severe COVID-19 pneumonia with acute respiratory failure. More studies are needed to further evaluate the role of helmet NIV especially in patients with initial PFR <150 mm Hg to define PFR/dPFR cutoff at the earliest time point for prediction of helmet-NIV success. How to cite this article Jha OK, Kumar S, Mehra S, Sircar M, Gupta R. Helmet NIV in Acute Hypoxemic Respiratory Failure due to COVID-19: Change in PaO₂/FiO₂ Ratio a Predictor of Success. Indian J Crit Care Med 2021;25(10):1137-1146.

Non-invasive ventilation in the palliative care of patients with chronic obstructive pulmonary disease: a scoping review protocol

INTRODUCTION

Patients with advanced chronic obstructive pulmonary disease (COPD) experience a great symptom burden. Breathlessness is a very frequently reported symptom that negatively affects all aspects of daily life and could lead to fear of dying. Non-invasive ventilation (NIV) could be an important palliative measure to manage breathlessness in patients with advanced COPD. We decided to conduct a scoping review to attain an overview of the existing research and to identify knowledge gaps. This scoping review aims to systematically map published studies on the use of NIV in the palliative care of COPD patients, including the perspectives and experiences of patients, families and healthcare professionals.

METHODS AND ANALYSIS

This scoping review will employ the framework of Arksey and O'Malley. The reporting will be guided by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses extension for Scoping Reviews checklist. A comprehensive and systematic search strategy will be developed in cooperation with an experienced librarian. Database searches will be conducted in AMED, PEDro, Embase, CINAHL, PsycInfo and MEDLINE in February 2021. Pairs of authors will independently assess studies' eligibility and extract data using a standardised data-charting form. The data will be inductively summarised and organised thematically. The results will be discussed with an advisory board consisting of nurses and physicians from respiratory and intensive care units.

ETHICS AND DISSEMINATION

Approval for the workshop with the advisory board has been attained from the Norwegian Centre for Research Data (480222), and approval will be attained from the Personal Data Protection Officers of the participating hospitals. All advisory board participants will sign an informed written consent before participation. The results could contribute to developing the body of evidence on the use of NIV in the palliative care of COPD patients and serve to identify directions for future research.

The relationship between person-centred care and the intensive care unit experience of critically ill patients: A multicentre cross-sectional survey

BACKGROUND

Person-centred care has the potential to improve the patient experience in the intensive care unit (ICU). However, the relationship between person-centred care perceived by critically ill patients and their ICU experience has yet to be determined.

OBJECTIVES

The aim of this study was to investigate the relationship between person-centred care and the ICU experience of critically ill patients.

METHODS

This study was a multicentre, cross-sectional survey involving 19 ICUs of four university hospitals in Busan, Korea. The survey was conducted from June 2019 to July 2020, and 787 patients who had been admitted to the ICU for more than 24 hours participated. We measured person-centred care using the Person-Centered Critical Care Nursing perceived by Patient Questionnaire. Participants' ICU experience was measured by the Korean version of the Intensive Care Experience Questionnaire that consists of four subscales. We analysed the relationship between person-centred care and each area of the ICU experience using multivariate linear regression.

RESULTS

Person-centred care was associated with 'awareness of surroundings' (β = 0.29, p < .001), 'frightening experiences' (β = -0.31, p < .001), and 'satisfaction with care' (β = 0.54, p < .001). However, there was no significant association between person-centred care and 'recall of experience'.

CONCLUSIONS

We observed that person-centred care was positively related to most of the ICU experiences of critically ill patients except for recall of experience. Further studies on developing person-centred nursing interventions are needed.

Association between prehospital arterial hypercapnia and mortality in acute heart failure: a retrospective cohort study

BACKGROUND

Acute Heart Failure (AHF) is a potentially lethal pathology and is often encountered in the prehospital setting. Although an association between prehospital arterial hypercapnia in AHF patients and admission in high-dependency and intensive care units has been previously described, there is little data to support an association between prehospital arterial hypercapnia and mortality in this population.

METHODS

This was a retrospective study based on electronically recorded prehospital medical files. All adult patients with AHF were included. Records lacking arterial blood gas data were excluded. Other exclusion criteria included the presence of a potentially confounding diagnosis, prehospital cardiac arrest, and inter-hospital transfers. Hypercapnia was defined as a PaCO2 higher than 6.0 kPa. The primary outcome was in-hospital mortality, and secondary outcomes were 7-day mortality and emergency room length of stay (ER LOS). Univariable and multivariable logistic regression models were used.

RESULTS

We included 225 patients in the analysis. Prehospital hypercapnia was found in 132 (58.7%) patients. In-hospital mortality was higher in patients with hypercapnia (17.4% [23/132] versus 6.5% [6/93], p = 0.016), with a crude odds-ratio of 3.06 (95%CI 1.19-7.85). After adjustment for pre-specified covariates, the adjusted OR was 3.18 (95%CI 1.22-8.26). The overall 7-day mortality was also higher in hypercapnic patients (13.6% versus 5.5%, p = 0.044), and ER LOS was shorter in this population (5.6 h versus 7.1 h, p = 0.018).

CONCLUSION

Prehospital hypercapnia is associated with an increase in in-hospital and 7-day mortality in patient with AHF.

The Coexistence of Chronic Obstructive Pulmonary Disease and Heart Failure

Chronic obstructive pulmonary disease (COPD) is a chronic illness that is widely prevalent within the United States and has been frequently associated with heart failure (HF). COPD is associated with progressive damage and inflammation of the airways leading to airflow obstruction and inadequate gas exchange. HF represents a decline in the normal functioning of the heart resulting in insufficient pumping of blood through the circulatory system. COPD and HF present with similar signs and symptoms with some variation.

There are many specific diagnostic tests and treatment modalities which we use to diagnose COPD and HF, but it becomes an issue when you come across a patient who has both conditions simultaneously. For example, attempting to use an X-ray to diagnose HF in a COPD patient is next to impossible because the results are manipulated by the COPD disease process. This is the case with many other diagnostic tests such as an electrocardiogram (ECG), chest radiography (X-ray), B-type natriuretic peptide (BNP), echocardiogram, cardiac magnetic resonance imaging (CMR), pulmonary function test (PFT), arterial blood gas (ABG), and exercise stress testing.

When a patient has both COPD and HF, it becomes more difficult to treat. Many treatments for HF have negative impacts on COPD patients and vice-versa, whereas some have also shown positive clinical outcomes in both diseases. It is agreeable that treatment has to be patient-centered and it can vary from case to case depending on the severity of the disease. Ultimately, in this review, we discuss COPD and HF and how they interplay in their diagnostic and treatment modalities to gain a better understanding of how to effectively manage patients who have been diagnosed with both conditions.

Dynamic prediction of late noninvasive ventilation failure in intensive care unit using a time adaptive machine model

BACKGROUND

Noninvasive ventilation (NIV) failure is strongly associated with poor prognosis. Nowadays, plenty of mature studies have been proposed to predict early NIV failure (within 48 hours of NIV), however, the prediction for late NIV failure (after 48 hours of NIV) lacks sufficient research. Late NIV failure delays intubation resulting in the increasing mortality of the patients. Therefore, it is of great significance to expeditiously predict the late NIV failure. In order to dynamically predict late NIV failure, we proposed a Time Updated Light Gradient Boosting Machine (TULightGBM) model.

MATERIAL AND METHODS

In this work, 5653 patients undergoing NIV over 48 hours were extracted from the database of Medical Information Mart for Intensive Care Ⅲ (MIMIC-Ⅲ) for model construction. The TULightGBM model consists of a series of sub-models which learn clinical information from updating data within 48 hours of NIV and integrates the outputs of the sub-models by the dynamic attention mechanism to predict late NIV failure. The performance of the proposed TULightGBM model was assessed by comparison with common models of logistic regression (LR), random forest (RF), LightGBM, eXtreme gradient boosting (XGBoost), artificial neural network (ANN), and long short-term memory (LSTM).

RESULTS

The TULightGBM model yielded prediction results at 8, 16, 24, 36, and 48 hours after the start of the NIV with dynamic AUC values of 0.8323, 0.8435, 0.8576, 0.8886, and 0.9123, respectively. Furthermore, the sensitivity, specificity, and accuracy of the TULightGBM model were 0.8207, 0.8164, and 0.8184, respectively. The proposed model achieved superior performance over other tested models.

CONCLUSIONS

The TULightGBM model is able to dynamically predict the late NIV failure with high accuracy and offer potential decision support for clinical practice.

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.

Diaphragm thickening fraction predicts noninvasive ventilation outcome: a preliminary physiological study

BACKGROUND

A correlation between unsuccessful noninvasive ventilation (NIV) and poor outcome has been suggested in de-novo Acute Respiratory Failure (ARF) patients. Consequently, it is of paramount importance to identify accurate predictors of NIV outcome. The aim of our preliminary study is to evaluate the Diaphragmatic Thickening Fraction (DTF) and the respiratory rate/DTF ratio as predictors of NIV outcome in de-novo ARF patients.

METHODS

Over 36 months, we studied patients admitted to the emergency department with a diagnosis of de-novo ARF and requiring NIV treatment. DTF and respiratory rate/DTF ratio were measured by 2 trained operators at baseline, at 1, 4, 12, 24, 48, 72 and 96 h of NIV treatment and/or until NIV discontinuation or intubation. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the ability of DTF and respiratory rate/DTF ratio to distinguish between patients who were successfully weaned and those who failed.

RESULTS

Eighteen patients were included. We found overall good repeatability of DTF assessment, with Intra-class Correlation Coefficient (ICC) of 0.82 (95% confidence interval 0.72-0.88). The cut-off values of DTF for prediction of NIV failure were < 36.3% and < 37.1% for the operator 1 and 2 (p < 0.0001), respectively. The cut-off value of respiratory rate/DTF ratio for prediction of NIV failure was > 0.6 for both operators (p < 0.0001).

CONCLUSION

DTF and respiratory rate/DTF ratio may both represent valid, feasible and noninvasive tools to predict NIV outcome in patients with de-novo ARF. Trial registration ClinicalTrials.gov Identifier: NCT02976233, registered 26 November 2016.

Application of aerosol therapy in respiratory diseases in children: A Saudi expert consensus

The Saudi Pediatric Pulmonology Association (SPPA) is a subsidiary of the Saudi Thoracic Society (STS), which consists of a group of Saudi experts with well-respected academic and clinical backgrounds in the fields of asthma and other respiratory diseases. The SPPA Expert Panel realized the need to draw up a clear, simple to understand, and easy to use guidance regarding the application of different aerosol therapies in respiratory diseases in children, due to the high prevalence and high economic burden of these diseases in Saudi Arabia. This statement was developed based on the available literature, new evidence, and experts' practice to come up with such consensuses about the usage of different aerosol therapies for the management of respiratory diseases in children (asthma and nonasthma) in different patient settings, including outpatient, emergency room, intensive care unit, and inpatient settings. For this purpose, SPPA has initiated and formed a national committee which consists of experts from concerned specialties (pediatric pulmonology, pediatric emergency, clinical pharmacology, pediatric respiratory therapy, as well as pediatric and neonatal intensive care). These committee members are from different healthcare sectors in Saudi Arabia (Ministry of Health, Ministry of Defence, Ministry of Education, and private healthcare sector). In addition to that, this committee is representing different regions in Saudi Arabia (Eastern, Central, and Western region). The subject was divided into several topics which were then assigned to at least two experts. The authors searched the literature according to their own strategies without central literature review. To achieve consensus, draft reports and recommendations were reviewed and voted on by the whole panel.

Perioperative Noninvasive Ventilation After Adult or Pediatric Surgery: A Comprehensive Review

Postoperative pulmonary complications and acute respiratory failure are among the leading causes of adverse postoperative outcomes. Noninvasive ventilation may safely and effectively prevent acute respiratory failure in high-risk patients after cardiothoracic surgery and after abdominal surgery. Moreover, noninvasive ventilation can be used to treat postoperative hypoxemia, particularly after abdominal surgery. Noninvasive ventilation also can be helpful to prevent or manage intraoperative acute respiratory failure during non-general anesthesia, primarily in patients with poor respiratory function. Finally, noninvasive ventilation is superior to standard preoxygenation in delaying desaturation during intubation in morbidly obese and in critically ill hypoxemic patients. The few available studies in children suggest that noninvasive ventilation could be safe and valuable in treating hypoxemic or hypercapnic acute respiratory failure after cardiac surgery; on the other hand, it could be dangerous after tracheoesophageal correction.

Helmet CPAP to treat hypoxic pneumonia outside the ICU: an observational study during the COVID-19 outbreak

BACKGROUND

Respiratory failure due to COVID-19 pneumonia is associated with high mortality and may overwhelm health care systems, due to the surge of patients requiring advanced respiratory support. Shortage of intensive care unit (ICU) beds required many patients to be treated outside the ICU despite severe gas exchange impairment. Helmet is an effective interface to provide continuous positive airway pressure (CPAP) noninvasively. We report data about the usefulness of helmet CPAP during pandemic, either as treatment, a bridge to intubation or a rescue therapy for patients with care limitations (DNI).

METHODS

In this observational study we collected data regarding patients failing standard oxygen therapy (i.e., non-rebreathing mask) due to COVID-19 pneumonia treated with a free flow helmet CPAP system. Patients' data were recorded before, at initiation of CPAP treatment and once a day, thereafter. CPAP failure was defined as a composite outcome of intubation or death.

RESULTS

A total of 306 patients were included; 42% were deemed as DNI. Helmet CPAP treatment was successful in 69% of the full treatment and 28% of the DNI patients (P < 0.001). With helmet CPAP, PaO₂/FiO₂ ratio doubled from about 100 to 200 mmHg (P < 0.001); respiratory rate decreased from 28 [22-32] to 24 [20-29] breaths per minute, P < 0.001). C-reactive protein, time to oxygen mask failure, age, PaO₂/FiO₂ during CPAP, number of comorbidities were independently associated with CPAP failure. Helmet CPAP was maintained for 6 [3-9] days, almost continuously during the first two days. None of the full treatment patients died before intubation in the wards.

CONCLUSIONS

Helmet CPAP treatment is feasible for several days outside the ICU, despite persistent impairment in gas exchange. It was used, without escalating to intubation, in the majority of full treatment patients after standard oxygen therapy failed. DNI patients could benefit from helmet CPAP as rescue therapy to improve survival.

TRIAL REGISTRATION

NCT04424992.

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.

Multidimensional prognostic index (MPI) predicts non-invasive ventilation failure in older adults with acute respiratory failure

BACKGROUND

Acute respiratory failure (ARF) is a very common complication among hospitalized older adults. Non-invasive ventilation (NIV) may avoid admission to intensive care units, intubation and their related complication, but still lacks specific indications in older adults. Multidimensional Prognostic Index (MPI) based on comprehensive geriatric assessment (CGA) could have a role in defining the short-term prognosis and the best candidates for NIV among older adults with ARF.

METHODS

This is a retrospective observational study which enrolled patients older than 70 years, consecutively admitted to an acute geriatric unit with ARF. A standardized CGA was used to calculate the MPI at admission. Multivariate Cox regression models were used to test if MPI score could predict in-hospital mortality and NIV failure. Receiver operator curve (ROC) analysis was used to identify the discriminatory power of MPI for NIV failure.

RESULTS

We enrolled 231 patients (88.2 ± 5.9 years, 47% females). Mean MPI at admission was 0.76±0.16. In-hospital mortality rate was 33.8%, with similar incidence in patients treated with and without NIV. Among NIV users (26.4%), NIV failure occurred in 39.3%. Higher MPI scores at admission significantly predicted in-hospital mortality (β=4.46, p<0.0001) among patients with ARF and NIV failure (β=7.82, p = 0.001) among NIV users. MPI showed good discriminatory power for NIV failure (area under the curve: 0.72, 95% CI: 0.58-0.85, p<0.001) with optimal cut-off at MPI value of 0.84.

CONCLUSIONS

MPI at admission might be a useful tool to early detect patients more at risk of in-hospital death and NIV failure among older adults with ARF.

Early versus late tracheal intubation in COVID-19 patients: a "pros/cons" debate also considering heart-lung interactions

The best timing of orotracheal intubation and invasive ventilation in COVID-19 patients with acute respiratory distress syndrome is unknown. The use of non-invasive ventilation, a life-saving technique in many medical conditions, is debated in patients with ARDS since prolonged NIV and delayed intubation may be harmful. Shortage of intensive care beds and ventilators during a respiratory pandemic can trigger a widespread use of early non-invasive ventilation in many hospitals but which is the best way to ventilate patients with severe bilateral pneumonia and severely increased spontaneous ventilation is controversial. Moreover, viral spreading to health-care workers and other hospitalized patients is an issue for any device used to administer oxygen. Even if protective mechanical ventilation is currently the gold standard for the management of acute respiratory distress syndrome, tracheal intubation is not without risks and is associated with delirium, hemodynamic instability, immobilization and post intensive care syndrome. Both invasive and non-invasive ventilation are associated with advantages and limitations that should be carefully considered when patients with COVID-19-ARDS need our attention. In the absence of strong evidence, in this review we highlight all the pro and con of these two different approaches.

Continuous positive airway pressure and pronation outside the intensive care unit in COVID 19 ARDS

BACKGROUND

The efficacy and safety of continuous positive airway pressure and respiratory physiotherapy outside the ntensive care unit during a pandemic.

METHODS

In this cohort study performed in February-May 2020 in a large teaching hospital in Milan, COVID-19 patients with adult respiratory distress syndrome receiving continuous positive airway pressure (positive end-expiratory pressure = 10 cm H2O, FiO2 = 0.6, daily treatment duration: 4x3hcycles) and respiratory physiotherapy including pronation outside the intensive care unit were followed up.

RESULTS

Of 90 ARDS patients treated with continuous positive airway pressure (45/90, 50% pronated at least once) outside the intensive care unit and with a median (interquartile) follow up of 37 (11-46) days, 45 (50%) were discharged at home, 28 (31%) were still hospitalized, and 17 (19%) died. Continuous positive airway pressure failure was recorded for 35 (39%) patients. Patient mobilization was associated with reduced failure rates (p=0.033). No safety issues were observed.

CONCLUSIONS

Continuous positive airway pressure with patient mobilization (including pronation) was effective and safe in patients with ARDS due to COVID-19 managed outside the intensive care unit setting during the pandemic.

The management of coronavirus disease 2019 (COVID-19)

In December 2019, a novel coronavirus causing severe acute respiratory disease occurred in Wuhan, China. It is an emerging infectious disease with widespread and rapid infectiousness. The World Health Organization declared the coronavirus outbreak to be a public health emergency of international concern on 31 January 2020. Severe COVID-19 patients should be managed and treated in a critical care unit. Performing a chest X-ray/CT can judge the severity of the disease. The management of COVID-19 patients includes epidemiological risk and patient isolation; treatment entails general supportive care, respiratory support, symptomatic treatment, nutritional support, psychological intervention, etc. The prognosis of the patients depends upon the severity of the disease, the patient's age, the underlying diseases of the patients, and the patient's overall medical condition. The management of COVID-19 should focus on early diagnosis, immediate isolation, general and optimized supportive care, and infection prevention and control.

Bedside risk stratification for mortality in patients with acute respiratory failure treated with noninvasive ventilation

Our hypothesis was that patients managed with noninvasive ventilation (NIV) on the wards could be risk-stratified with initial pulse oximetry/fraction of inspired oxygen (SpO₂/FiO₂) ratios and tidal volumes (Vte). A prospective study of consecutive patients with acute respiratory failure requiring NIV on the wards was conducted. A multivariate logistic regression model and a negative binomial regression model were used. A total of 403 patients (55.8% women) had a mean age of 65.0 ± 14.9 years with a mean body mass index of 32.1 ± 11.1 kg/m². The 28-day mortality was 14.1%, and the intubation rate was 16.1%. Pneumonia was associated with the highest 28-day mortality (22.5%) and rate of intubation (36.7%) when compared with chronic obstructive pulmonary disease (4.4% and 7.3%) or congestive heart failure (22.2% and 13.4%). The SpO₂/FiO₂ groups were <214 (26.6%), 214 -357 (66.0%), and ≥357 (7.4%). Those in the SpO₂/FiO₂ < 214 group had a higher 28-day mortality rate (odds ratio [OR] = 8.19; 95% confidence interval [CI] 1.02 -65.7), intubation rate (OR = 3.7; 95% CI 1.1 -12.1), intensive care unit admission rate (OR = 2.9; 95% CI 1.2 -7.4), and length of stay (relative risk = 2.0; 95% CI 1.3 -3.0). A Vte/predicted body weight <7.7 mL/kg was associated with increased intubations (OR = 3.1; 95% CI 1.3 -7.4), intensive care unit admissions (OR = 2.5; 95% CI 1.3 -4.6), and 30-day readmissions (OR = 2.9; 95% CI 1.2 -6.8). In conclusion, in patients without acute respiratory distress syndrome who had acute respiratory failure managed with noninvasive ventilation on the wards, severe hypoxemia as assessed by a simple SpO₂/FiO₂ ≤ 214 was associated with poor outcomes.

Dose-response characteristics of noninvasive ventilation in acute respiratory failure

Acute noninvasive ventilation (NIV) is a well-established therapy for acute respiratory failure but the dose–response characteristics of this therapy have not been defined. The aim of this study was to define this dose–response relationship.

This study was a retrospective review of patients receiving NIV for acute respiratory failure in a tertiary hospital respiratory high-dependency unit between July 2012 and June 2017. Mask-on time (rather than the period that NIV was in use) as the “dose” was compared with hospital survival as the “response”.

654 patients were included, 594 (91%) with hypercapnic respiratory failure (HCRF). NIV was used for a median (interquartile range (IQR)) duration of 2.74 (1.51–4.73) days and median (IQR) mask-on time was 34 (18–60) h (56.1% (41.2–69.5%) of treatment time). There was evidence of a dose–response relationship in the HCRF group up to a ceiling of 24 h mask-on time, but not in the hypoxaemic respiratory failure (HRF) group. There was a difference in survival with as little as 2 h mask-on time (92% compared with 73%; p<0.001). Patients requiring NIV for 80–100% of therapy time had lower survival.

We conclude that there is evidence of a dose–response relationship between cumulative NIV usage (mask-on time) and survival from as little as 2 h to a ceiling of ∼24 h in HCRF, but not in HRF.

Acute NIV in respiratory failure has a dose–response effect on survival from as little as 2 h of therapyhttp://bit.ly/2okErQZ

Impact of Using a Novel Gastric Feeding Tube Adaptor on Patient's Comfort and Air Leaks During Non-invasive Mechanical Ventilation

INTRODUCTION

The presence of oral or naso-enteral probes during non-invasive mechanical ventilation (NIMV) increases the risk of leakage and patient discomfort. The objective of this study was to evaluate the effectiveness of a novel tube adapter for NIMV (TA-NIMV) in relation to leakage and comfort level.

METHODS

A non-randomized quasi-experimental design was performed in an adult intensive care unit of a highly complex hospital, in which patients were their own controls. We included adult patients who required NIV with oronasal mask and who simultaneously had oral or naso-enteric tubes. The interventions were as follows: every participant received two therapies, one with the TA-NIMV and one conventional therapy of NIMV (CT-NIMV). Comfort could be evaluated in 99 patients with a Glasgow Coma Scale of 15. The outcomes of interest was the average percentage of air leak and patient comfort during each intervention.

RESULTS

196 patients were included in the study during a 16-month period. The mean air leak percentage was 9.2% [standard deviation (SD), 7.7] during TA-NIMV and 32.5% (SD, 12.5) during CT-NIMV (p<0.001). 84.9% reported being comfortable or very comfortable during TA-VMNI. 66.7% Uncomfortable or Very uncomfortable during CT-NIMV (p<0.001).

CONCLUSION

Higher comfort levels and lower air leakage volume percentages were achieved using the TA-NIMV than those achieved by CT-NIMV.

Prophylactic Noninvasive Ventilation Versus Conventional Care in Patients After Cardiac Surgery

BACKGROUND

Cardiac surgery can be accompanied by postoperative complications, which are associated with increased postoperative morbidity and mortality. Therefore, it is necessary to investigate the effect of prophylactic noninvasive ventilation (NIV) after extubation versus conventional pulmonary care on complications after cardiac surgery.

MATERIALS AND METHODS

An electronic search of PubMed, Cochrane Library, Ovid, and EMBASE was conducted to find randomized controlled trials which compared the effect of prophylactic NIV with controlled strategies on complications and which were published before April 2018.

RESULTS

Ten studies (1011 patients) were included in the final analysis. The atelectasis rate was 32.6% in the prophylactic-NIV group, which was lower than that in the control group (48.71%). Prophylactic NIV could lower the rate of atelectasis, reintubation, and other respiratory complications (pleural effusion, pneumonia, and hypoxia) (odds ratio = 0.43, 0.33, and 0.45; 95% confidence interval: 0.21-0.88, 0. 13-0.84, 0.27-0.75; P = 0.02, 0.02, and 0.002, respectively). The effect on cardiac and distal organ complications (P = 0.07) and hospital mortality (P = 0.62) might be limited.

CONCLUSIONS

Prophylactic NIV is associated with a lower rate of postoperative pulmonary complications. The effect on the other complications and hospital mortality might be limited. Further evidence with randomized controlled trials can discern the benefits.

Noninvasive Ventilation Is Interrupted Frequently and Mostly Used at Night in the Pediatric Intensive Care Unit

BACKGROUND

Noninvasive ventilation (NIV) is commonly used to support children with respiratory failure, but detailed patterns of real-world use are lacking. The aim of our study was to describe use patterns of NIV via electronic medical record (EMR) data.

METHODS

We performed a retrospective electronic chart review in a tertiary care pediatric ICU in the United States. Subjects admitted to the pediatric ICU from 2014 to 2017 who were mechanically ventilated were included in the study.

RESULTS

The median number of discrete device episodes, defined as a time on support without interruption, was 20 (interquartile range [IQR] 8-49) per subject. The median duration of bi-level positive airway pressure (BPAP) support prior to interruption was 6.3 h (IQR 2.4-10.4); the median duration of CPAP was 6 h (IQR 2.1-10.4). Interruptions to BPAP had a median duration of 6.3 h (IQR 2-15.5); interruptions to CPAP had a median duration of 8.6 h (IQR 2.2-16.8). Use of NIV followed a diurnal pattern, with 44% of BPAP and 42% of CPAP subjects initiating support between 7:00 pm and midnight, and 49% of BPAP and 46% of CPAP subjects stopping support between 5:00 am and 10:00 am.

CONCLUSIONS

NIV was frequently interrupted, and initiation and discontinuation of NIV follows a diurnal pattern. Use of EMR data collected for routine clinical care allowed the analysis of granular details of typical use patterns. Understanding NIV use patterns may be particularly important to understanding the burden of pediatric ICU bed utilization for nocturnal NIV. To our knowledge, this is the first study to examine in detail the use of pediatric NIV and to define diurnal use and frequent interruptions to support.

Non-invAsive VentIlation for early General wArd respiraTory failurE (NAVIGATE): A multicenter randomized controlled study. Protocol and statistical analysis plan

OBJECTIVE

Few randomized trials have evaluated the use of non-invasive ventilation (NIV) for early acute respiratory failure (ARF) in non-intensive care unit (ICU) wards. The aim of this study is to test the hypothesis that early NIV for mild-moderate ARF in non-ICU wards can prevent development of severe ARF.

DESIGN

Pragmatic, parallel group, randomized, controlled, multicenter trial.

SETTING

Non-intensive care wards of tertiary centers.

PATIENTS

Non-ICU ward patients with mild to moderate ARF without an established indication for NIV.

INTERVENTIONS

Patients will be randomized to receive or not receive NIV in addition to best available care.

MEASUREMENTS AND MAIN RESULTS

We will enroll 520 patients, 260 in each group. The primary endpoint of the study will be the development of severe ARF. Secondary endpoints will be 28-day mortality, length of hospital stay, safety of NIV in non-ICU environments, and a composite endpoint of all in-hospital respiratory complications.

CONCLUSIONS

This trial will help determine whether the early use of NIV in non-ICU wards can prevent progression from mild-moderate ARF to severe ARF.

Respiratory Failure, Noninvasive Ventilation, and Symptom Burden: An Observational Study

BACKGROUND

Noninvasive ventilation (NIV) is commonly used to manage acute respiratory failure due to decompensated cardiorespiratory disease. We describe symptom burden in this population.

MEASURES

Fifty consecutive, consenting, English-speaking, cognitively intact patients, admitted to wards other than the intensive care unit in a tertiary teaching hospital and treated with NIV for hypercapnic respiratory failure, were recruited. The 14-item Condensed Memorial Symptom Assessment Scale was used to assess physical and psychological symptoms within 36 hours of commencing NIV. Breathlessness (using Borg score), pain location and intensity using a numerical rating scale, and four symptoms potentially prevalent in patients undergoing NIV (cough, sputum, gastric bloating, and dry eyes) were also assessed.

OUTCOMES

Patients reported a median of 10 symptoms (IQR 9-13). A median of five symptoms (IQR 3-7) were rated as severe. Breathlessness was the most prevalent and most distressing symptom, with participants reporting a mean maximum Borg score of 7.55 over the 24 hours before admission. Dry mouth, lack of energy, cough, sputum, difficulty sleeping, and psychological symptoms were prevalent. Pain, when reported, was of moderate intensity and contributed to distress.

CONCLUSIONS/LESSONS LEARNED

This study describes the patient-reported symptoms occurring during an episode of acute respiratory failure. Understanding the symptom profile of patients in this setting may allow clinicians to target symptom relief while simultaneously managing respiratory failure, enhancing care.

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.