Defining successful non-invasive ventilation initiation: Data from a real-life cohort

Telemonitoring in Non-invasive Ventilation

Telemonitoring in non-invasive ventilation is constantly evolving to enable follow-up of adults and children. Depending on the device and manufacturer, different ventilator variables are displayed on web-based platforms. However, high-granularity measurement is not always available remotely, which precludes breath-by-breath waveforms and precise monitoring of nocturnal gas exchange. Therefore, telemonitoring is mainly useful for monitoring utilization of the device, leaks, and respiratory events. Coordinated relationships between patients, homecare providers, and hospital teams are necessary to transform available data into diagnosis and actions. Telemonitoring is time and cost-consuming. The balance between cost, workload, and clinical benefit should be further evaluated.

[Take-home messages from the 2nd COPD 2023 Biennial of the French Society of Respiratory Diseases. Placing the patient at the center of the care pathway]

INTRODUCTION

The second COPD Biennial organized by the COPD working group of the French Society of Respiratory Diseases took place in Paris (Cochin) on 13th December 2023.

STATE OF THE ART

Major trends in 2023 were discussed; they encompassed concepts, definitions, biologics, care pathways, pulmonary rehabilitation and complex situations entailed by respiratory infections, cardiovascular comorbidities and pulmonary hypertension, and modalities of oxygen therapy and ventilation.

PERSPECTIVES

The different talks underlined major changes in COPD including the concepts of pre-COPD, etiotypes, health trajectories and new definitions of exacerbation. Recent results in biologics for COPD open the door to new pharmacological options. Assessment of current care pathways in France highlighted some causes for concern. For example, pulmonary rehabilitation is a key but insufficiently practiced element. Respiratory infections require careful assessment and treatments. Diagnosis and treatment of cardiovascular comorbidities and pulmonary hypertension are of paramount importance. As of late, oxygen therapy and ventilation modalities have evolved, and are beginning to afford more personalized options.

CONCLUSIONS

As regards COPD, a personalized approach is crucial, placing the patient at the center of the care pathway and facilitating coordination between healthcare providers.

Does PaCO2 correction have an impact on survival of patients with chronic respiratory failure and long-term non-invasive ventilation?

Background and objective

Non-invasive ventilation (NIV) improves survival of patients with chronic respiratory failure (CRF). Most often, pressure settings are made to normalize arterial blood gases. However, this objective is not always achieved due to intolerance to increased pressure or poor compliance. Few studies have assessed the effect of persistent hypercapnia on ventilated patients' survival. Data from the Pays de la Loire Respiratory Health Research Institute cohort were analyzed to answer this question.

Study design and methods

NIV-treated adults enrolled between 2009 and 2019 were divided into 5 subgroups: obesity-hypoventilation syndrome (OHS), COPD, obese COPD, neuromuscular disease (NMD) and chest wall disease (CWD). PaCO2 correction was defined as the achievement of a PaCO2 < 6 kPa or a 20% decrease in baseline PaCO₂ in COPD patients. The endpoint was all-cause mortality. Follow-up was censored in case of NIV discontinuation.

Results

Data from 431 patients were analyzed. Median survival was 103 months and 148 patients died. Overall, PaCO2 correction was achieved in 74% of patients. Bivariate analysis did not show any survival difference between patients who achievedPaCO₂ correction and those who remained hypercapnic: overall population: p = 0.74; COPD: p = 0.97; obese COPD: p = 0.28; OHS: p = 0.93; NMD: p = 0.84; CWD: p = 0.28.

Conclusion

Moderate residual hypercapnia under NIV does not negatively impact survival in CRF patients. In individuals with poor tolerance of pressure increases, residual hypercapnia can therefore be tolerated under long-term NIV. Larger studies, especially with a higher number of patients with residual PaCO2 > 7 kPa, are needed to confirm these results.

Effects of non-invasive ventilation on sleep in chronic hypercapnic respiratory failure

Chronic respiratory disease can exacerbate the normal physiological changes in ventilation observed in healthy individuals during sleep, leading to sleep-disordered breathing, nocturnal hypoventilation, sleep disruption and chronic respiratory failure. Therefore, patients with obesity, slowly and rapidly progressive neuromuscular disease and chronic obstructive airways disease report poor sleep quality. Non-invasive ventilation (NIV) is a complex intervention used to treat sleep-disordered breathing and nocturnal hypoventilation with overnight physiological studies demonstrating improvement in sleep-disordered breathing and nocturnal hypoventilation, and clinical trials demonstrating improved outcomes for patients. However, the impact on subjective and objective sleep quality is dependent on the tools used to measure sleep quality and the patient population. As home NIV becomes more commonly used, there is a need to conduct studies focused on sleep quality, and the relationship between sleep quality and health-related quality of life, in all patient groups, in order to allow the clinician to provide clear patient-centred information.

An exposed/unexposed cohort study assessing the effectiveness, the safety and the survival of patients established on home non-invasive ventilation after 80 years old

BACKGROUND

Little is known about the use of long-term non-invasive ventilation (NIV) in the elderly. We aimed to assess if the effectiveness of long-term NIV of patients ≥ 80 years (older) was not greatly inferior to that of patients < 75 years (younger).

METHODS

This retrospective exposed/unexposed cohort study included all patients established on long-term NIV treated at Rouen University Hospital between 2017 and 2019. Follow-up data were collected at the first visit following NIV initiation. The primary outcome was daytime PaCO2 with a non-inferiority margin of 50% of the improvement of PaCO2 for older patients compared to younger patients.

RESULTS

We included 55 older patients and 88 younger patients. After adjustment on the baseline PaCO2, the mean daytime PaCO2 was reduced by 0.95 (95% CI: 0.67; 1.23) kPa in older patients compared to1.03 (95% CI: 0.81; 1.24) kPa in younger patients for a ratio of improvements estimated at 0.95/1.03 = 0.93 (95% CI: 0.59; 1.27, one-sided p = 0.007 for non-inferiority to 0.50). Median (interquartile range) daily use was 6 (4; 8.1) hours in older versus 7.3 (5; 8.4) hours in younger patients. No significant differences were seen in the quality of sleep and NIV safety. The 24-months survival was 63.6% in older and 87.2% in younger patients.

CONCLUSIONS

effectiveness and safety seemed acceptable in older patients, with a life expectancy long enough to expect a mid-term benefit, suggesting that initiation of long-term NIV should not be refused only based on age. Prospective studies are needed.

Home NIV treatment quality in patients with chronic respiratory failure having participated to the French nationwide telemonitoring experimental program (The TELVENT study)

BACKGROUND

The ETAPES program is a national telemedicine experiment conducted in France between 2018 and 2023 to investigate whether home non-invasive ventilation (NIV) telemonitoring improves healthcare pathways in patients with chronic respiratory failure (CRF) and impacts healthcare organization. The program provides a combination of therapeutic education and NIV telemonitoring with data processed by an algorithm generating alerts. The TELVENT study objective was to analyze the evolution of ventilation quality in patients included in the ETAPES program.

METHODS

Multicentric cohort study on patients undergoing long-term NIV included in the ETAPES program between September 2018 and December 2020 and who did not refuse the use of their data for this research. Data were obtained from homecare provider databases. The primary endpoint was to attain successful NIV treatment, which was determined by a combination of daily NIV usage for > 4 h per day, low leaks, and a low apnea-hypopnea index (AHI) identified by the NIV device. Respiratory disability was assessed using the DIRECT questionnaire.

RESULTS

329 patients were included in the study of which 145 had COPD and 83 had started NIV and ETAPES within one-month delay. Approximately 25% of patients did not achieve the criteria for successful NIV at ETAPES entry. The proportion of patients with successful NIV treatment increased to 86.8% at six months (p = 0.003, Cochran-Armitage trend test) regardless of NIV history and continued to increase at 12 months in newly equipped NIV patients (93.8%, at month 12, p = 0.0026 for trend test). Over time, a significant increase in NIV use and compliance was observed, while AHI significantly decreased in the overall population. No significant decrease was observed for non-intentional leaks. Approximately 4.9 alerts were generated per patient per 6 months. Their number and type (low NIV use, high AHI or leaks) differed among patients based on their NIV history. Respiratory disability score decreased over time compared with baseline.

CONCLUSION

The TELVENT study highlights the importance of remote NIV monitoring to rapidly identify patients with unsuccessful ventilation. The combination of remote monitoring and therapeutic education may improve the quality of home NIV, especially in the first months of treatment.

Quality of life in patients with chronic respiratory failure on home mechanical ventilation

Home mechanical ventilation (HMV) is a treatment for chronic respiratory failure that has shown clinical and cost effectiveness in patients with underlying COPD, obesity-related respiratory failure and neuromuscular disease (NMD). By treating chronic respiratory failure with adequate adherence to HMV, improvement in patient-reported outcomes including health-related quality of life (HRQoL) have been evaluated using general and disease-specific quantitative, semi-qualitative and qualitative methods. However, the treatment response in terms of trajectory of change in HRQoL is not uniform across the restrictive and obstructive disease groups. In this review, the effect of HMV on HRQoL across the domains of symptom perception, physical wellbeing, mental wellbeing, anxiety, depression, self-efficacy and sleep quality in stable and post-acute COPD, rapidly progressive NMD (such as amyotrophic lateral sclerosis), inherited NMD (including Duchenne muscular dystrophy) and obesity-related respiratory failure will be discussed.

Does one size fit all? An update on chronic ventilatory support in different respiratory illnesses

Home noninvasive ventilation (HNIV) improves outcomes in different disease categories. In this article, we discuss indications for when and how to initiate HNIV in COPD, obesity hypoventilation syndrome (OHS) and neuromuscular disorders (NMD). While in COPD, significant diurnal hypercapnia and high-intensity HNIV are essential ingredients for success, in NMD and OHS, early respiratory changes are best detected during sleep through oxy-capnography associated (or not) with respiratory polygraphy. In COPD and OHS, it is crucial to consider the coexistence of obstructive sleep apnoea because treatment with continuous positive airway pressure may be the simplest and most effective treatment that should be proposed even in hypercapnic patients as first-line therapy. In NMD, the need for continuous HNIV and eventual switching to tracheostomy ventilation makes this group's management more challenging. Achieving successful HNIV by improving quality of sleep, quality of life and keeping a good adherence to the therapy is a challenge, above all in COPD patients. In OHS patients, on top of HNIV, initiation of other interventions such as weight loss management is crucial. More resources should be invested in improving all these aspects. Telemonitoring represents a promising method to improve titration and follow-up of HNIV.

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.

Highlights from the Respiratory Failure and Mechanical Ventilation 2022 Conference

The Respiratory Intensive Care Assembly of the European Respiratory Society gathered in Berlin to organise the second Respiratory Failure and Mechanical Ventilation Conference in June 2022. The conference covered several key points of acute and chronic respiratory failure in adults. During the 3-day conference, ventilatory strategies, patient selection, diagnostic approaches, treatment and health-related quality of life topics were addressed by a panel of international experts. Lectures delivered during the event have been summarised by Early Career Members of the Assembly and take-home messages highlighted.

Responses of Bilevel Ventilators to Unintentional Leak: A Bench Study

BACKGROUND

The impact of leaks has mainly been assessed in bench models using continuous leak patterns which did not reflect real-life leakage. We aimed to assess the impact of the pattern and intensity of unintentional leakage (UL) using several respiratory models.

METHODS

An active artificial lung (ASL 5000) was connected to three bilevel-ventilators set in pressure mode; the experiments were carried out with three lung mechanics (COPD, OHS and NMD) with and without upper airway obstruction. Triggering delay, work of breathing, pressure rise time, inspiratory pressure, tidal volume, cycling delay and the asynchrony index were measured at 0, 6, 24 and 36 L/min of UL. We generated continuous and inspiratory UL.

RESULTS

Compared to 0 L/min of UL, triggering delays were significantly higher with 36 L/min of UL (+27 ms) and pressure rise times were longer (+71 ms). Cycling delays increased from -4 [-250-169] ms to 150 [-173-207] ms at, respectively 0 L/min and 36 L/min of UL and work of breathing increased from 0.15 [0.12-0.29] J/L to 0.19 [0.16-0.36] J/L. Inspiratory leakage pattern significantly increased triggering delays (+35 ms) and cycling delays (+263 ms) but decreased delivered pressure (-0.94 cmH₂O) compared to continuous leakage pattern. Simulated upper airway obstruction significantly increased triggering delay (+199 ms), cycling delays (+371 ms), and decreased tidal volume (-407 mL) and pressure rise times (-56 ms).

CONCLUSIONS

The pattern of leakage impacted more the device performances than the magnitude of the leakage per se. Flow limitation negatively reduced all ventilator performances.

Transitioning from hospital to home with non-invasive ventilation: who benefits? Results of a cohort study

Background

Non-invasive ventilation (NIV) is effective in a variety of acute respiratory illnesses in hospitalised patients. Home NIV is effective for stable patients with hypercapnia due to neuromuscular or chronic pulmonary disease. However, there are little data to guide which patients may benefit from NIV immediately following hospitalisation with hypercapnia.

Objective

To evaluate outcomes of patients with daytime hypercapnia at the end of an acute hospital admission.

Design

Retrospective cohort study.

Participants

Entry into the cohort was by querying the hospital electronic medical system for consultations regarding NIV after discharge. Cases received NIV and controls did not. We extracted data on demographics, ICD-9 diagnoses and medications coded at admission, blood gas measurements and dates of discharge, first readmission and death.

Intervention

None.

Main measurement

Time from hospital discharge to mortality or readmission.

Key results

We identified 585 cases and 53 controls who survived to discharge at the index admission. Cases and controls were broadly similar in age and Charlson Comorbidity Index. In the whole cohort, cases treated with home NIV were at increased risk of death compared with controls (HR 1.88 95% CI 1.17 to 3.03). In multivariate Cox regression for all-cause mortality, poor prognostic factors were increasing age (HR 1.03 per year, 95% CI 1.02 to 1.04), cardiac failure (HR 1.31, 95% CI 1.01 to 1.67) and failure to attend NIV follow-up (HR 2.33, 95% CI 1.33 to 4.10). In contrast, chronic respiratory disease was associated with improved prognosis (HR 0.77, 95% CI 0.61 to 0.97) as was sleep apnoea (HR 0.44, 95% CI 0.23 to 0.83). Cases did not have different time-to-readmission compared with controls (HR 1.42 95% CI 0.99 to 2.02).

Conclusion

Transitioning to home NIV after a hypercapnic hospitalisation may be useful in younger, co-operative patients with chronic respiratory disease. For older patients or those with cardiac failure, home NIV may not be beneficial and may potentially be harmful.