Severe Community-Acquired Pneumonia: Noninvasive Mechanical Ventilation, Intubation, and HFNT.

Severe acute respiratory failure (ARF) is a major issue in patients with severe community-acquired pneumonia (CAP). Standard oxygen therapy is the first-line therapy for ARF in the less severe cases. However, respiratory supports may be delivered in more severe clinical condition. In cases with life-threatening ARF, invasive mechanical ventilation (IMV) will be required. Noninvasive strategies such as high-flow nasal therapy (HFNT) or noninvasive ventilation (NIV) by either face mask or helmet might cover the gap between standard oxygen and IMV. The objective of all the supporting measures for ARF is to gain time for the antimicrobial treatment to cure the pneumonia. There is uncertainty regarding which patients with severe CAP are most likely to benefit from each noninvasive support strategy. HFNT may be the first-line approach in the majority of patients. While NIV may be relatively contraindicated in patients with excessive secretions, facial hair/structure resulting in air leaks or poor compliance, NIV may be preferable in those with increased work of breathing, respiratory muscle fatigue, and congestive heart failure, in which the positive pressure of NIV may positively impact hemodynamics. A trial of NIV might be considered for select patients with hypoxemic ARF if there are no contraindications, with close monitoring by an experienced clinical team who can intubate patients promptly if they deteriorate. In such cases, individual clinician judgement is key to choose NIV, interface, and settings. Due to the paucity of studies addressing IMV in this population, the protective mechanical ventilation strategies recommended by guidelines for acute respiratory distress syndrome can be reasonably applied in patients with severe CAP.

The Diaphragmatic Initiated Ventilatory Assist (DIVA) trial: study protocol for a randomized controlled trial comparing rates of extubation failure in extremely premature infants undergoing extubation to non-invasive neurally adjusted ventilatory assist versus non-synchronized nasal intermittent positive pressure ventilation.

BACKGROUND: Invasive mechanical ventilation contributes to bronchopulmonary dysplasia (BPD), the most common complication of prematurity and the leading respiratory cause of childhood morbidity. Non-invasive ventilation (NIV) may limit invasive ventilation exposure and can be either synchronized or non-synchronized (NS). Pooled data suggest synchronized forms may be superior. Non-invasive neurally adjusted ventilatory assist (NIV-NAVA) delivers NIV synchronized to the neural signal for breathing, which is detected with a specialized catheter. The DIVA (Diaphragmatic Initiated Ventilatory Assist) trial aims to determine in infants born 240/7-276/7 weeks' gestation undergoing extubation whether NIV-NAVA compared to non-synchronized nasal intermittent positive pressure ventilation (NS-NIPPV) reduces the incidence of extubation failure within 5 days of extubation. METHODS: This is a prospective, unblinded, pragmatic, multicenter phase III randomized clinical trial. Inclusion criteria are preterm infants 24-276/7 weeks gestational age who were intubated within the first 7 days of life for at least 12 h and are undergoing extubation in the first 28 postnatal days. All sites will enter an initial run-in phase, where all infants are allocated to NIV-NAVA, and an independent technical committee assesses site performance. Subsequently, all enrolled infants are randomized to NIV-NAVA or NS-NIPPV at extubation. The primary outcome is extubation failure within 5 days of extubation, defined as any of the following: (1) rise in FiO2 at least 20% from pre-extubation for > 2 h, (2) pH ≤ 7.20 or pCO2 ≥ 70 mmHg; (3) > 1 apnea requiring positive pressure ventilation (PPV) or ≥ 6 apneas requiring stimulation within 6 h; (4) emergent intubation for cardiovascular instability or surgery. Our sample size of 478 provides 90% power to detect a 15% absolute reduction in the primary outcome. Enrolled infants will be followed for safety and secondary outcomes through 36 weeks' postmenstrual age, discharge, death, or transfer. DISCUSSION: The DIVA trial is the first large multicenter trial designed to assess the impact of NIV-NAVA on relevant clinical outcomes for preterm infants. The DIVA trial design incorporates input from clinical NAVA experts and includes innovative features, such as a run-in phase, to ensure consistent technical performance across sites. TRIAL REGISTRATION: www. CLINICALTRIALS: gov , trial identifier NCT05446272 , registered July 6, 2022.

High-flow nasal oxygen versus conventional oxygen therapy and noninvasive ventilation in COVID-19 respiratory failure: a systematic review and network meta-analysis of randomised controlled trials.

BACKGROUND: Noninvasive methods of respiratory support, including noninvasive ventilation (NIV), continuous positive airway pressure (CPAP), and high-flow nasal oxygen (HFNO), are potential strategies to prevent progression to requirement for invasive mechanical ventilation in acute hypoxaemic respiratory failure. The COVID-19 pandemic provided an opportunity to understand the utility of noninvasive respiratory support among a homogeneous cohort of patients with contemporary management of acute respiratory distress syndrome. We performed a network meta-analysis of studies evaluating the efficacy of NIV (including CPAP) and HFNO, compared with conventional oxygen therapy (COT), in patients with COVID-19. METHODS: PubMed, Embase, and the Cochrane library were searched in May 2023. Standard random-effects meta-analysis was used first to estimate all direct pairwise associations and the results from all studies were combined using frequentist network meta-analysis. Primary outcome was treatment failure, defined as discontinuation of HFNO, NIV, or COT despite progressive disease. Secondary outcome was mortality. RESULTS: We included data from eight RCTs with 2302 patients, (756 [33%] assigned to COT, 371 [16%] to NIV, and 1175 [51%] to HFNO). The odds of treatment failure were similar for NIV (P=0.33) and HFNO (P=0.25), and both were similar to that for COT (reference category). The odds of mortality were similar for all three treatments (odds ratio for NIV vs COT: 1.06 [0.46-2.44] and HFNO vs COT: 0.97 [0.57-1.65]). CONCLUSIONS: Noninvasive ventilation, high-flow nasal oxygen, and conventional oxygen therapy are comparable with regards to treatment failure and mortality in COVID-19-associated acute respiratory failure. PROSPERO REGISTRATION: CRD42023426495.

In acute hypoxemic respiratory failure, noninvasive oxygenation methods may reduce death vs. standard oxygen therapy.

SOURCE CITATION: Pitre T, Zeraatkar D, Kachkovski GV, et al. Noninvasive oxygenation strategies in adult patients with acute hypoxemic respiratory failure: a systematic review and network meta-analysis. Chest. 2023;164:913-928. 37085046.

Oxygen debt as a predictor of high-flow nasal cannula therapy failure in SARS-CoV-2 patients with acute respiratory failure: A retrospective cohort study.

BACKGROUND: Severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) is known for its rapid progression to acute hypoxemic respiratory failure (AHRF). The increased use of oxygen therapy during the pandemic and the progression of AHRF have highlighted the need to promptly determine the need for orotracheal intubation (OTI). OBJETIVE: To determine the validity of quantitative measurement of oxygen debt (DEOx) according to arterial gases compared to the use of iROX in patients with high-flow nasal cannula (HFNC) therapy requirement, presenting with acute respiratory failure as a consequence of SARS-CoV-2 infection. In addition, we aimed to identify the factors associated with the need for orotracheal intubation (OTI). METHODS: A retrospective observational cohort study of a database collected from patients with SARS-CoV-2 infection admitted to intensive care units with AHRF and had received HFNC upon admission during the Covid-19 pandemic (March 23, 2020 through August 02, 2021). The variables of interest were factors determining the predictive ability of DEOx and iROX. We used a multiple logarithmic regression model to correct for confounding and mixed-effects variables, and validated for OTI in patients treated with HFNC. RESULTS: From a total of 373 patients treated with HFNC, 317 patients (84.9%) required invasive mechanical ventilation. APACHE II (AOR 1.44; 95% CI: 1.14-1.83, p 0,032), vasopressor use (AOR 27.7; 95% CI: 1.83 - 420,63, p 0,017), and DEOx (AOR 1.26; 95% CI: 1.10 - 1.44, p 0,001) were associated with the need for intubation. The predictive model between iROX and DEOx evidenced an AUC of 0.535 vs. 0.606, respectively, with a DEOx cut off point of 7.14 (±10.16, p < 0.01). DEOx as an independent factor of OTI presents an OR 2,48 with cut point 4.5 mlO2/kg (AUC 0.780, CI 95%, 0.753 - 0.808, p < 0.01). CONCLUSIONS: DEOx is a valuable measurment to identify the need for OTI in patients with SARS-CoV-2 who were under management with HFNC with a predictive value superior to iROX, being a reproducible and valid quantitative method for the need OTI that can be implemented in other critically illconditions. Further studies are required to characterize the usefulness of DEOx more precisely.

Comparison between high-flow nasal cannula and conventional oxygen therapy in COVID-19 patients: a systematic review and meta-analysis.

BACKGROUND: High-flow nasal cannula (HFNC) and conventional oxygen therapy (COT) are important respiratory support strategies for acute hypoxemic respiratory failure (AHRF) in coronavirus disease 2019 (COVID-19) patients. However, the results are conflicting for the risk of intubation with HFNC as compared to COT. OBJECTIVES: We systematically synthesized the outcomes of HFNC relative to COT in COVID-19 patients with AHRF and evaluated these outcomes in relevant subpopulations. DESIGN: This study was designed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. DATA SOURCES AND METHODS: We searched PubMed, EMBASE, Web of Science, Scopus, ClinicalTrials.gov, medRxiv, BioRxiv, and the Cochrane Central Register of Controlled Trials for randomized controlled trials and observational studies that compared the efficacy of HFNC with COT in patients with COVID-19-related AHRF. Primary outcomes were intubation rate and mortality rate. Secondary outcomes were the ratio of arterial oxygen partial pressure to fractional inspired oxygen (PaO2/FiO2), respiratory rate, hospital length of stay, intensive care unit (ICU) length of stay, and days free from invasive mechanical ventilation. RESULTS: In total, 20 studies with 5732 patients were included. We found a decreased risk of requiring intubation in HFNC compared to COT [odds ratio (OR) = 0.61, 95% confidence interval (CI): 0.46-0.82, p = 0.0009, I2 = 75%]. Similarly, we found HFNC was associated with lower risk of intubation rate compared to COT in the subgroup of patients with baseline PaO2/FiO2 < 200 mmHg (OR = 0.69, 95% CI: 0.55-0.86, p = 0.0007, I2 = 45%), and who were in ICU settings at enrollment (OR = 0.57, 95% CI: 0.38-0.85, p = 0.005, I2 = 80%). HFNC was associated with an improvement of PaO2/FiO2 and respiratory rate compared to COT. The use of HFNC compared to COT did not reduce the mortality rate, days free from invasive mechanical ventilation, hospital length of stay, or ICU length of stay. CONCLUSION: Compared to COT, HFNC may decrease the need for tracheal intubation in patients with COVID-19-related AHRF, particularly among patients with baseline PaO2/FiO2 < 200 mmHg and those in ICU settings. TRIAL REGISTRATION: This systematic review and meta-analysis protocol was prospectively registered with PROSPERO (no. CRD42022339072).

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.

Nutrition practices in hospitalized adults receiving noninvasive forms of respiratory support: A scoping review.

The use of noninvasive respiratory support is increasing, with noninvasive ventilation (NIV) and high-flow nasal cannula providing unique barriers to nutrition support. Limited data related to nutrition management for these patients in the intensive care unit (ICU) exist; however, the literature in non-critically ill patients is not well described, and its improvement may help to inform practice within the ICU. Therefore, a scoping review was conducted of MEDLINE, EmCare, and Cumulative Index of Nursing and Allied Health Literature (CINAHL) databases on August 18, 2022, to identify original publications that included adult patients receiving noninvasive respiratory support in a hospital setting with data related to nutrition management. Data were extracted on study design, population, details of respiratory support, and concepts relating to nutrition management (grouped into nutrition screening, assessment, delivery route, intake, and anthropometry). Eleven studies were included, most of which were small (<100 patients), single-center, observational trials in patients receiving NIV only. Five studies reported results related to route of nutrition and nutrition assessment, two on anthropometry, and one each on quantifying intake and nutrition screening; some studies reported multiple parameters. There was a lack of consensus regarding the ideal method for nutrition assessment and route of nutrition. Oral nutrition was the route most frequently reported, yet calorie and protein delivery via this route were inadequate, and barriers to intake included poor appetite, fatigue, and patient cognition. Future research should address barriers pertinent to this population and the impact of nutrition on outcomes.

Quantitative brainstem and spinal MRI in amyotrophic lateral sclerosis: implications for predicting noninvasive ventilation needs.

BACKGROUND: Respiratory complications resulting from motor neurons degeneration are the primary cause of death in amyotrophic lateral sclerosis (ALS). Predicting the need for non-invasive ventilation (NIV) in ALS is important for advance care planning and clinical trial design. The aim of this study was to assess the potential of quantitative MRI at the brainstem and spinal cord levels to predict the need for NIV during the first six months after diagnosis. METHODS: Forty-one ALS patients underwent MRI and spirometry shortly after diagnosis. The need for NIV was monitored according to French health guidelines for 6 months. The performance of four regression models based on: clinical variables, brainstem structures volumes, cervical spinal measurements, and combined variables were compared to predict the need for NIV within this period. RESULTS: Both the clinical model (R2 = 0.28, AUC = 0.85, AICc = 42.67, BIC = 49.8) and the brainstem structures' volumes model (R2 = 0.30, AUC = 0.85, AICc = 40.13, BIC = 46.99) demonstrated good predictive performance. In addition, cervical spinal cord measurements model similar performance (R2 = 0.338, AUC = 0.87, AICc = 37.99, BIC = 44.49). Notably, the combined model incorporating predictors from all three models yielded the best performance (R2 = 0.60, AUC = 0.959, AICc = 36.38, BIC = 44.8). These findings are supported by observed positive correlations between brainstem volumes, cervical (C4/C7) cross-sectional area, and spirometry-measured lung volumes. CONCLUSIONS: Our study shows that brainstem volumes and spinal cord area are promising measures to predict respiratory intervention needs in ALS.

Association between goal nutrition and intubation in patients with bronchiolitis on noninvasive ventilation: A retrospective cohort study.

BACKGROUND: Acute bronchiolitis causes many hospitalizations in children younger than 2 years. Early enteral nutrition is associated with improved outcomes in these patients. However, often nutrition is withheld when patients require noninvasive respiratory support because of the risk of aspiration worsening respiratory failure, possibly requiring intubation. We hypothesize that achieving goal energy intake is associated with a lower intubation rate in hospitalized children with bronchiolitis who require noninvasive ventilation. METHODS: This retrospective cohort study examined the association between goal enteral nutrition (60% of dietary reference energy intake) and intubation rates. We grouped patients by severity of illness and compared intubation rates in those who met goal energy to those who did not. We use stratified analysis methods (for both level of respiratory support and feeding route) to evaluate progression to intubation. RESULTS: Of the 272 patients, 215 met goal feeds. These groups had similar demographics, but the goal-feeds group started on higher respiratory support in the pediatric intensive care unit. We found that 4.65% of the patients who met goal feeds required intubation compared with 24.6% of patients who did not meet goal feeds (P < 0.0001), even after controlling for respiratory status at admission and time of feed initiation and feeding route. CONCLUSION: We observed when adjusting for severity, feeding route, and respiratory support, achieving goal energy intake remained associated with a lower rate of intubation, without higher rates of aspiration. Confounding factors include practice variation and difference in severity of illness that objective scoring may have missed.

Pediatric long-term noninvasive respiratory support in children with central nervous system disorders.

RATIONALE: The use of long-term noninvasive respiratory support is increasing in children along with an extension of indications, in particular in children with central nervous system (CNS) disorders. OBJECTIVE: The aim of this study was to describe the characteristics of children with CNS disorders treated with long-term noninvasive respiratory support in France. METHODS: Data were collected from 27 French pediatric university centers through an anonymous questionnaire filled for every child treated with noninvasive ventilatory support ≥3 months on 1st June 2019. MAIN RESULTS: The data of 182 patients (55% boys, median age: 10.2 [5.4;14.8] years old [range: 0.3-25]) were collected: 35 (19%) patients had nontumoral spinal cord injury, 22 (12%) CNS tumors, 63 (35%) multiple disabilities, 26 (14%) central alveolar hypoventilation and 36 (20%) other CNS disorders. Seventy five percent of the patients were treated with noninvasive ventilation (NIV) and 25% with continuous positive airway pressure (CPAP). The main investigations performed before CPAP/NIV initiation were nocturnal gas exchange recordings, alone or coupled with poly(somno)graphy (in 29% and 34% of the patients, respectively). CPAP/NIV was started in an acute setting in 10% of the patients. Median adherence was 8 [6;10] hours/night, with 12% of patients using treatment <4 h/day. Nasal mask was the most common interface (70%). Airway clearance techniques were used by 31% of patients. CONCLUSION: CPAP/NIV may be a therapeutic option in children with CNS disorders. Future studies should assess treatment efficacy and patient reported outcome measures.

Effect of different noninvasive ventilation interfaces on the prevention of facial pressure injury: A network meta-analysis.

OBJECTIVE: To assess the effect of different noninvasive ventilation interfaces on preventing the facial pressure injury. METHODS: This network meta-analysis was conducted following the PRISMA reporting guidelines. Seven electronic databases were systematically searched for randomised controlled trials about the comparative effectiveness of different interfaces in preventing facial pressure injury with noninvasive ventilation in adults and newborns from inception to June 2023. The acronym of PICOS was used and the keywords as well as inclusion/exclusion criteria were determined. Study selection and data extraction were performed by two independent reviewers. The Cochrane risk of bias assessment tool was used to assess the methodological quality. RESULTS: A total of 78 randomised controlled trials involving 7,291 patients were included. The results of network meta-analysis showed that the effectiveness of the eight noninvasive ventilation interfaces on the prevention of facial pressure injury was in the order of: nasal cannula > full-face mask > rotation of nasal mask with nasal prongs > helmet > nasal mask > oronasal mask > nasal prongs > face mask. The use of full-face mask in adults and nasal cannula in newborns had the best effect on preventing the incidence of facial pressure injury. CONCLUSIONS: The use of full-face mask in adults and nasal cannula in newborns had the most clinical advantage in preventing the incidence of facial pressure injury and were worthy promoting in clinical practice. IMPLICATIONS FOR CLINICAL PRACTICE: This study provides a certain theoretical basis for the selection of appropriate interface for patients with noninvasive ventilation. Clinical practitioners should choose the appropriate interfaces based on the patient's specific condition to reduce the incidence of facial pressure injury, enhance patient comfort, and improve the effectiveness of respiratory therapy.

PHYSIO+++: protocol for a pilot randomised controlled trial assessing the feasibility of physiotherapist-led non-invasive ventilation for patients with hypoxaemia following abdominal surgery.

INTRODUCTION: Few clinical trials have investigated physiotherapy interventions to treat hypoxaemia following abdominal surgery. The objective of this study is to determine the feasibility and safety of conducting a clinical trial of physiotherapist-led non-invasive ventilation (NIV). METHODS AND ANALYSIS: This single-centre, 50-patient, parallel-group, assessor blinded, pilot feasibility randomised controlled trial with concealed allocation will enrol spontaneously ventilating adults with hypoxaemia within 72 hours of major abdominal surgery. Participants will receive either (1) usual care physiotherapy of a single education session (talk), daily walking of 10-15 min (walk) and four sessions of coached deep breathing and coughing (breathe) or (2) usual care physiotherapy plus four 30 min sessions of physiotherapist-led NIV delivered over 2 postoperative days. Primary feasibility and safety outcome measures are; number of eligible patients recruited per week, total time of NIV treatment delivered, acceptability of treatments to patients and clinicians and incidence of adverse events. Secondary feasibility outcomes include measures of recruitment and treatment adherence. Exploratory outcome measures include change in respiratory parameters, postoperative pulmonary complications, length of hospital stay, health-related quality of life, postoperative activity levels and mortality. ETHICS AND DISSEMINATION: Ethics approval has been obtained from the relevant institution. Results will be published to inform future research. TRIAL REGISTRATION NUMBER: ACTRN12622000839707.

High-intensity non-invasive ventilation during exercise-training versus without in people with very severe COPD and chronic hypercapnic respiratory failure: a randomised controlled trial.

BACKGROUND: People with very severe chronic obstructive pulmonary disease (COPD) using nocturnal non-invasive ventilation (NIV) for chronic hypercapnic respiratory failure (CHRF) experience reduced exercise capacity and severe dyspnoea during exercise training (ET). The use of NIV during ET can personalise training during pulmonary rehabilitation (PR) but whether high-intensity NIV (HI-NIV) during exercise is accepted and improves outcomes in these extremely physically limited patients is unknown. The aim of this trial was to determine if ET with HI-NIV during PR was more effective than without at improving exercise capacity and reducing dyspnoea during exercise. METHODS: Patients with COPD, CHRF and nocturnal-NIV were randomised to supervised cycle-ET as part of PR with HI-NIV or without (control). Primary outcome was change in cycle endurance time (ΔCETtime), while secondary outcomes were dyspnoea at isotime during the cycle endurance test and during ET-sessions and for the HI-NIV group, post-trial preferred exercising method. RESULTS: Twenty-six participants (forced expiratory volume in 1 s 22±7%pred, PaCO251±7 mm Hg) completed the trial (HI-NIV: n=13, ET: IPAP 26±3/EPAP 6±1 cm H2O; control n=13). At completion of a 3 week ET-programme, no significant between-group differences in ΔCETtime were seen (HI-NIV-control: Δ105 s 95% CI (-92 to 302), p=0.608). Within-group ΔCETtime was significant (HI-NIV: +246 s 95% CI (61 to 432); control: +141 s 95% CI (60 to 222); all p<0.05). The number of responders (Δ>minimal important difference (MID)101 s: n=53.8%) was the same in both groups for absolute ΔCETtime and 69.2% of control and 76.9% of the HI-NIV group had a %change>MID33%.Compared with control, the HI-NIV group reported less isotime dyspnoea (Δ-2.0 pts. 95% CI (-3.2 to -0.8), p=0.005) and during ET (Δ-3.2 pts. 95% CI (-4.6 to -1.9), p<0.001). Most of the HI-NIV group (n=12/13) preferred exercising with NIV. CONCLUSION: In this small group of patients with very severe COPD requiring nocturnal NIV, participation in an ET-programme during PR significantly improved exercise capacity irrespective of HI-NIV use. Reported dyspnoea was in favour of HI-NIV. TRIAL REGISTRATION NUMBER: NCT03803358.

Noninvasive Home Mechanical Ventilation for Stable Hypercapnic COPD: A Clinical Respiratory Review from Canadian Perspectives.

Acute short-term noninvasive ventilation (NIV) for hypercapnic respiratory failure in chronic obstructive pulmonary disease (COPD) has well-established benefits; however, the role of long-term home NIV remains controversial. In the past decade, studies utilizing aggressive NIV settings to maximally reduce carbon dioxide levels (PaCO2) have resulted in several positive clinical trials and led to updated guidelines on home NIV for stable hypercapnic COPD patients. This clinical respiratory review discusses the high-intensity NIV approach, summarizes recent key trials and guidelines pertaining to home NIV in COPD, and considers key clinical questions for future research and application in the Canadian context. With recent evidence and Canadian Thoracic Society (CTS) guidelines supporting the use of NIV in carefully selected COPD patients with persistent daytime hypercapnia, we believe it is time to reconsider our approach.

Generation of Aerosols by Noninvasive Respiratory Support Modalities: A Systematic Review and Meta-Analysis.

Importance: Infection control guidelines have historically classified high-flow nasal oxygen and noninvasive ventilation as aerosol-generating procedures that require specialized infection prevention and control measures. Objective: To evaluate the current evidence that high-flow nasal oxygen and noninvasive ventilation are associated with pathogen-laden aerosols and aerosol generation. Data Sources: A systematic search of EMBASE and PubMed/MEDLINE up to March 15, 2023, and CINAHL and ClinicalTrials.gov up to August 1, 2023, was performed. Study Selection: Observational and (quasi-)experimental studies of patients or healthy volunteers supported with high-flow nasal oxygen or noninvasive ventilation were selected. Data Extraction and Synthesis: Three reviewers were involved in independent study screening, assessment of risk of bias, and data extraction. Data from observational studies were pooled using a random-effects model at both sample and patient levels. Sensitivity analyses were performed to assess the influence of model choice. Main Outcomes and Measures: The main outcomes were the detection of pathogens in air samples and the quantity of aerosol particles. Results: Twenty-four studies were included, of which 12 involved measurements in patients and 15 in healthy volunteers. Five observational studies on SARS-CoV-2 detection in a total of 212 air samples during high-flow nasal oxygen in 152 patients with COVID-19 were pooled for meta-analysis. There was no association between high-flow nasal oxygen and pathogen-laden aerosols (odds ratios for positive samples, 0.73 [95% CI, 0.15-3.55] at the sample level and 0.80 [95% CI, 0.14-4.59] at the patient level). Two studies assessed SARS-CoV-2 detection during noninvasive ventilation (84 air samples from 72 patients). There was no association between noninvasive ventilation and pathogen-laden aerosols (odds ratios for positive samples, 0.38 [95% CI, 0.03-4.63] at the sample level and 0.43 [95% CI, 0.01-27.12] at the patient level). None of the studies in healthy volunteers reported clinically relevant increases in aerosol particle production by high-flow nasal oxygen or noninvasive ventilation. Conclusions and Relevance: This systematic review and meta-analysis found no association between high-flow nasal oxygen or noninvasive ventilation and increased airborne pathogen detection or aerosol generation. These findings argue against classifying high-flow nasal oxygen or noninvasive ventilation as aerosol-generating procedures or differentiating infection prevention and control practices for patients receiving these modalities.

A pragmatic, open-label, multi-center, randomized controlled clinical trial on the rotational use of interfaces vs standard of care in patients treated with noninvasive positive pressure ventilation for acute hypercapnic respiratory failure: the ROTAtional-USE of interface STUDY (ROTA-USE STUDY).

BACKGROUND: In the last decades, noninvasive ventilation (NIV) has been increasingly used to support patients with hypercapnic and hypoxemic acute respiratory failure. Pressure ulcers are a frequently observed NIV-related adverse effect, directly related to interface type and exposure time. Switching to a different interface has been proposed as a solution to improve patient comfort. However, large studies investigating the benefit of this strategy are not available. Thus, the aim of the ROTAtional-USE of interface STUDY (ROTA-USE STUDY) is to investigate whether a protocolized rotational use of interfaces during NIV is effective in reducing the incidence of pressure ulcers. METHODS: The ROTA-USE STUDY is a pragmatic, parallel arm, open-label, multicenter, spontaneous, non-profit, randomized controlled trial requiring non-significant risk medical devices, with the aim to determine whether a rotational strategy of NIV interfaces is associated with a lower incidence of pressure ulcers compared to the standard of care. In the intervention group, NIV mask will be randomly chosen and rotated every 6 h. In the control group, mask will be chosen according to the standard of care of the participating centers and changed in case of discomfort or in the presence of new pressure sores. In both groups, the skin underneath the mask will be inspected every 12 h for any possible damage by blinded assessors. The primary outcome is the proportion of patients developing new pressure sores at 36 h from randomization. The secondary outcomes are (i) onset of pressure sores measured at different time points, i.e., 12, 24, 36, 48, 60, 72, 84, and 96 h; (ii) number and stage of pressure sores and comfort measured at 12, 24, 36, 48, 60, 72, 84, and 96 h; and (iii) the economic impact of the protocolized rotational use of interfaces. A sample size of 239 subjects per group (intervention and control) is estimated to detect a 10% absolute difference in the proportion of patients developing pressure sores at 36 h. DISCUSSION: The development of pressure ulcers is a common side effect of NIV that negatively affects the patients' comfort and tolerance, often leading to NIV failure and adverse outcomes. The ROTA-USE STUDY will determine whether a protocolized rotational approach can reduce the incidence, number, and severity of pressure ulcers in NIV-treated patients. TRIAL REGISTRATION: ClinicalTrials.gov NCT05513508. Registered on August 24, 2022.

High flow nasal cannula use is associated with increased hospital length of stay for pediatric asthma.

BACKGROUND: High flow nasal cannula (HFNC) is a respiratory device increasingly used to treat asthma. Recent mechanistic studies have shown that nebulized medications may have reduced delivery with HFNC, which may impair asthma treatment. This study evaluated the association between HFNC use for pediatric asthma and hospital length of stay (LOS). METHODS: This was a retrospective matched cohort study. Cases included patients aged 2-18 years hospitalized between January 2010 and December 2021 with asthma and received HFNC treatment. Controls were selected using logistic regression propensity score matching based on demographics, vital signs, medications, imaging, and social and environmental determinants of health. The primary outcome was hospital LOS. RESULTS: A total of 23,659 encounters met eligibility criteria, and of these 1766 cases included HFNC treatment with a suitable matched control. Cases were well-matched in demographics, social and environmental determinants of health, and clinical characteristics including use of adjunctive asthma therapies. The median hospital LOS for study cases was significantly higher at 87 h (interquartile range [IQR]: 61-145) compared to 66 h (IQR: 43-105) in the matched controls (p < 0.01). There was no significant difference in the rate of intubation and mechanical ventilation (8.9% vs. 7.6%, p = .18); however, the use of NIV was significantly higher in the cases than the control group (21.3% vs. 6.7%, p < .01). CONCLUSION: In this study of children hospitalized for asthma, HFNC use was associated with increased hospital LOS compared to matched controls. Further research using more granular data and additional relevant variables is needed to validate these findings.

Associations With Severe Desaturation Events Among Children Receiving Noninvasive Respiratory Support at Time of Intubation.

BACKGROUND: Endotracheal intubation is a common procedure associated with adverse events, including severe desaturation. Many patients receive noninvasive respiratory support to reduce the need for intubation. There are minimal data about the association between noninvasive respiratory support and the risk of a severe desaturation event during intubation. We aim to differentiate patients based on the level of noninvasive respiratory support, analyze the severe desaturation event by groups, and identify modifiable risk factors. METHODS: Oral intubations, excluding tube exchanges or re-intubation after unplanned extubation, from October 2018 through July 2020, at the study site were reviewed. A severe desaturation event was defined as [Formula: see text] < 70% or a >15% decrease from baseline in cyanotic heart disease. We analyzed outcomes by 4 groups: room air/nasal cannula (≤0.5 L/kg/min), high-flow nasal cannula (HFNC) (0.5-2 L/kg/min), high HFNC (≥2 L/kg/min), and noninvasive ventilation (NIV). RESULTS: Of 243 subjects who were intubated, 31% were receiving room air/nasal cannula, 25% were receiving HFNC, 18% were receiving high HFNC, and 26% were receiving NIV. Twelve percent of all the subjects had a severe desaturation event. In a univariate analysis, the incidence of a severe desaturation event was similar among all levels of respiratory support (P = .14). A severe desaturation event was more likely in those subjects who were receiving [Formula: see text] ≥ 0.6 at the time of the decision to intubate (19.6%) versus [Formula: see text] < 0.6 (8.1%) (P = .02). The duration of noninvasive respiratory support was longer (5 vs 1 h; P = .02) among those with a severe desaturation event. In a regression analysis, when adjusting for ≥2 intubation attempts pre-intubation, NIV use was independently associated with increased odds of severe desaturation events (odds ratio 3.14, CI 1.08-10.5). CONCLUSIONS: Results of our study suggest that [Formula: see text] > 0.60, the duration of noninvasive respiratory support, and exposure to NIV before an intubation are risk factors of severe desaturation events during intubation.

Effect of Intensity of Home Noninvasive Ventilation in Individuals With Neuromuscular and Chest Wall Disorders: A Systematic Review and Meta-Analysis of Individual Participant Data

Introduction: Home noninvasive ventilation (NIV), targeting a reduction of carbon dioxide with a combination of sufficient inspiratory support and backup-rate improves outcomes in patients with chronic obstructive pulmonary disease. The aim of this systematic review with individual participant data (IPD) meta-analysis was to evaluate the effects of intensity of home NIV on respiratory outcomes in individuals with slowly progressive neuromuscular (NMD) or chest-wall disorders (CWD). Methods: Controlled, non-controlled and cohort studies indexed between January-2000 and December-2020 were sought from Medline, Embase and the Cochrane Central Register. Outcomes were diurnal PaCO2, PaO2, daily NIV usage, and interface type (PROSPERO-CRD 42021245121). NIV intensity was defined according to the Z-score of the product of pressure support (or tidal volume) and backup-rate. Results: 16 eligible studies were identified; we obtained IPD for 7 studies (176 participants: 113-NMD; 63-CWD). The reduction in PaCO2 was greater with higher baseline PaCO2. NIV intensity per se was not associated with improved PaCO2 except in individuals with CWD and the most severe baseline hypercapnia. Similar results were found for PaO2. Daily NIV usage was associated with improvement in gas exchange but not with NIV intensity. No association between NIV intensity and interface type was found. Conclusion: Following home NIV initiation in NMD or CWD patients, no relationship was observed between NIV intensity and PaCO2, except in individuals with the most severe CWD. The amount of daily NIV usage, rather than intensity, is key to improving hypoventilation in this population during the first few months after introduction of therapy. (AU)