Advances in non‐invasive positive airway pressure technology

The prevalence of non-invasive ventilation and long-term oxygen treatment in Helsinki University Hospital area, Finland

BACKGROUND

Chronic respiratory failure (CRF) can be treated at home with non-invasive ventilation (NIV) and/or long-term oxygen (LTOT). The prevalence of these treatments is largely unknown. We aimed to clarify the prevalence and indications of the treatments, and the three-year mortality of the treated patients in the Helsinki University Hospital (HUH) area in Finland.

METHODS

In this retrospective study we analyzed the prevalence of adult CRF patients treated with NIV and/or LTOT on 1.1.2018 and followed these patients until 1.1.2021. Data collected included the underlying diagnosis, patient characteristics, information on treatment initiation and from the last follow-up visit, and mortality during the three-year follow-up. Patients with home invasive mechanical ventilation or sleep apnea were excluded.

RESULTS

On 1.1.2018, we had a total of 815 patients treated with NIV and/or LTOT in the Helsinki University Hospital (HUH) area, with a population of 1.4 million. The prevalence of NIV was 35.4 per 100,000, of LTOT 24.6 per 100,000 and of the treatments combined 60.0 per 100,000. Almost half, 44.5%, were treated with NIV, 41.0% with LTOT, and 14.4% underwent both. The most common diagnostic groups were chronic obstructive pulmonary disease (COPD) (33.3%) and obesity-hypoventilation syndrome (OHS) (26.6%). The three-year mortality in all patients was 45.2%. In the COPD and OHS groups the mortality was 61.3% and 21.2%. In NIV treated patients, the treatment durations varied from COPD patients 5.3 years to restrictive chest wall disease patients 11.4 years. The age-adjusted Charlson co-morbidity index (ACCI) median for all patients was 3.0.

CONCLUSIONS

NIV and LTOT are common treatments in CRF. The prevalence in HUH area was comparable to other western countries. As the ACCI index shows, the treated patients were fragile, with multiple co-morbidities, and their mortality was high. Treatment duration and survival vary greatly depending on the underlying diagnosis.

Treatment of Cheyne-Stokes Respiration in Heart Failure with Adaptive Servo-Ventilation: An Integrative Model

The SERVE-HF (Treatment of Predominant Central Sleep Apnea by Adaptive Servo Ventilation in Patients with Heart Failure) multicenter trial found a small but significant increase in all-cause and cardiovascular mortality in patients assigned to adaptive servo-ventilation (ASV) versus guideline-based medical treatment. To better understand the physiological underpinnings of this clinical outcome, we employ an integrative computer model to simulate congestive heart failure with Cheyne-Stokes respiration (CHF-CSR) in subjects with a broad spectrum of underlying pathogenetic mechanisms, as well as to determine the in silico changes in cardiopulmonary and autonomic physiology resulting from ASV. Our simulation results demonstrate that while the elimination of CSR through ASV can partially restore cardiorespiratory and autonomic physiology toward normality in the vast majority of CHF phenotypes, the degree of restoration can be highly variable, depending on the combination of CHF mechanisms in play. The group with the lowest left ventricular ejection fraction (LVEF) appears to be most vulnerable to the potentially adverse effects of ASV, but the level of pulmonary capillary wedge pressure (PCWP) plays an important role in determining the nature of these effects.

Endorsement of: "treatment of adult obstructive sleep apnea with positive airway pressure: an American academy of Sleep Medicine Clinical Practice Guideline" by World Sleep Society

Guidelines for the evaluation and management of sleep disorders from national societies provide recommendations that may be regionally appropriate but may not always be practical or relevant in other parts of the world. A task force of experts from the World Sleep Society's (WSS) International Sleep Medicine Guidelines Committee and Sleep and Breathing Disorders Taskforce reviewed the American Academy of Sleep Medicine's Clinical Practice Guideline on the Treatment of Adult Obstructive Sleep Apnea (OSA) with Positive Airway Pressure with respect to its relevance and applicability to the practice of sleep medicine by sleep specialists in various regions of the world. To improve the evaluation of the guideline, surveys were sent by the senior author and the WSS to approximately 800 sleep doctors around the world to query the availability of OSA treatments in their respective region. The task force and the WSS guidelines committee endorsed the AASM's CPAP guidelines with respect to the indications for PAP therapy, utilization of different PAP modalities, and concurrent strategies to improve outcomes, noting appropriate caveats for universal applicability.

Comparing effectiveness of intelligent volume-assured pressure support (iVAPS) vs bi-level positive airway pressure spontaneous/timed (BPAP S/T) for hypercapnic respiratory failure in chronic obstructive pulmonary disease

BACKGROUND AND AIM

Intelligent volume-assured pressure support (iVAPS) is a relatively new hybrid mode of non-invasive ventilation (NIV). There is still limited evidence for iVAPS. The aim of this study was to compare the effectiveness of iVAPS to that of bi-level positive airway pressure spontaneous/timed (BPAP S/T) in patients with acute hypercapnic respiratory failure or acute-on-chronic hypercapnic respiratory failure caused by acute exacerbation of chronic obstructive pulmonary disease (AECOPD) in the emergency department.

MATERIAL AND METHODS

This was an observational, retrospective study. Eighty-two patients with hypercapnic respiratory failure caused by AECOPD, who were admitted to our emergency department, were analysed. Arterial blood gas (ABG) parameters, length of hospital stay and rate of intensive care unit (ICU) admission were compared between iVAPS and BPAP S/T.

RESULTS

A total of 82 patients (26 females, 56 males, mean age 68.26 ± 11.63 years) who were treated with iVAPS (N = 26) or BPAP S/T (N = 56) were enrolled. There were no significant differences between two modes with respect to demographics such as age, gender, presence of comorbidity, usage of long-term oxygen therapy or NIV, and the baseline ABG parameters. The presence of pneumonia was significantly higher in BPAP S/T (P = .01). The rate of ICU admission was 26.9% in iVAPS vs 25% in BPAP S/T. The mean length of hospital stay was 11.5 ± 12.3 days in iVAPS and 9.7 ± 7.4 days in BPAP S/T (P = .53). The mean values of ABG parameters at the 1st and 24th hours of NIV therapy did not differ in both groups.

CONCLUSION

Both modes were similarly effective in the management of appropriately selected patients with hypercapnic respiratory failure caused by AECOPD. Hence, we underline that NIV mode selection in the emergency department should be performed in line with experiences of clinicians/institutions and accessibility of ventilator devices/modes.

Efficacy and adherence of noninvasive ventilation treatment in children with Down syndrome

OBJECTIVE

Children with Down syndrome (DS) have an increased prevalence of obstructive sleep apnea (OSA). Noninvasive ventilation (NIV) is a common modality of OSA treatment in this cohort. This study aimed to measure adherence and efficiency of NIV delivery in children with DS.

STUDY DESIGN

This was a retrospective cohort study involving 106 children with confirmed OSA and home NIV with downloadable data capacity. Children were divided into DS (n = 44) and non-DS cohorts (n = 62). Adherence, clinical outcomes apnea-hypopnoea index (AHI), positive airway pressure delivery, and leakage were recorded and compared between DS and non-DS cohorts and within the DS cohort based on past surgical history.

RESULTS

Significantly greater NIV usage was observed in the DS cohort, they showed more consistent use with an increased percentage of days used relative to their non-DS counterparts (78.95 ± 2.26 vs. 72.11 ± 2.14, p = .031). However, despite greater usage, poorer clinical outcomes in the form of increased AHI (p = .0493) was observed in the DS cohort, where significantly greater leakage was also shown 41.00 ± 1.61 L/min versus 36.52 ± 1.18 L/min (p = .022). Twenty children with DS had prior cardiac surgery; compliance across all parameters was significantly reduced relative to those without.

CONCLUSION

These data confirm that satisfactory NIV adherence is achievable in children with DS. However, we have identified excessive system leak at the machine-patient interface as a factor, which could undermine NIV efficacy in children with DS.

Validating respiratory index of auto-titrating positive airway pressure device with polysomnography

PURPOSE

Positive airway pressure (PAP) devices have been widely used as the first line of treatment in obstructive sleep apnea (OSA). Most advanced PAP devices support the estimation of respiratory index (RI) using the patient's mask airflow. In addition to the compliance factor for PAP device use, which is important for monitoring patient sleep health, RI is also becoming important for monitoring. However, there are few reports that validate RI of a PAP device with polysomnography.

METHODS

Between January 2015 and December 2017, 50 participants were enrolled who were diagnosed with OSA and prescribed auto-titration PAP (APAP) devices. The RIs of participants were measured at night using APAP devices, concurrently with electroencephalography, respiratory inductance plethysmography sensors, and other polysomnographic sensors in a sleep laboratory. The respiratory-related data of APAP were prospectively analyzed with the manually scored polysomnographic data.

RESULTS

The apnea-hypopnea index and apnea index showed a statistically close relationship between the auto-scored respiratory data from the APAP device and the manually scored respiratory data from polysomnographic sensors. Obstructive apnea and central apnea indices showed relatively low correlations. The differences between the auto-scored RI and manually scored RI were influenced by BMI, waist circumference, weight, oxygen saturation, and respiratory distress indices of diagnostic polysomnographic factors.

CONCLUSIONS

The RIs of APAP devices have a tendency to be underestimated or mismatched when compared with polysomnography. Sleep specialists are advised to consider additional anthropometric and diagnostic factors to account for these differences during PAP treatment.

The future of sleep-disordered breathing: A public health crisis

Find the whole series here https://onlinelibrary.wiley.com/doi/toc/10.1111/(ISSN)1440-1843.new-frontiers-in-sleep-disordered-breathing See cover image.

Long-Term Noninvasive Ventilation in the Geneva Lake Area: Indications, Prevalence, and Modalities

BACKGROUND

Noninvasive ventilation (NIV) is standard of care for chronic hypercapnic respiratory failure, but indications, devices, and ventilatory modes are in constant evolution.

RESEARCH QUESTION

To describe changes in prevalence and indications for NIV over a 15-year period; to provide a comprehensive report of characteristics of the population treated (age, comorbidities, and anthropometric data), mode of implementation and follow-up, devices, modes and settings used, physiological data, compliance, and data from ventilator software.

STUDY DESIGN AND METHODS

Cross-sectional observational study designed to include all subjects under NIV followed by all structures involved in NIV in the Cantons of Geneva and Vaud (1,288,378 inhabitants).

RESULTS

A total of 489 patients under NIV were included. Prevalence increased 2.5-fold since 2000 reaching 38 per 100,000 inhabitants. Median age was 71 years, with 31% being > 75 years of age. Patients had been under NIV for a median of 39 months and had an average of 3 ± 1.8 comorbidities; 55% were obese. COPD (including overlap syndrome) was the most important patient group, followed by obesity hypoventilation syndrome (OHS) (26%). Daytime Paco₂ was most often normalized. Adherence to treatment was satisfactory, with 8% only using their device < 3.5 h/d. Bilevel positive pressure ventilators in spontaneous/timed mode was the default mode (86%), with a low use of autotitrating modes. NIV was initiated electively in 50% of the population, in a hospital setting in 82%, and as outpatients in 15%.

INTERPRETATION

Use of NIV is increasing rapidly in this area, and the population treated is aging, comorbid, and frequently obese. COPD is presently the leading indication followed by OHS.

TRIAL REGISTRY

ClinicalTrials.gov; No.: NCT04054570; URL: www.clinicaltrials.gov.