Non-invasive ventilation abolishes the IL-6 response to exercise in muscle-wasted COPD patients: A pilot study

Noninvasive ventilation acutely improves endothelial function in exacerbated COPD patients

PURPOSE

Acute exacerbation of chronic obstructive pulmonary disease (AECOPD) is associated with an elevated risk of cardiovascular events, which can be linked to endothelial dysfunction. In this study, we aimed to investigate whether noninvasive ventilation (NIV) acutely changes endothelial function in hospitalized AECOPD patients.

METHODS

Twenty-one AECOPD patients were assessed in a hospital ward setting from 24 to 48 h after admission. NIV was applied using a ventilator with bilevel pressure support. Before and after NIV protocol, patients were evaluated regarding (1) endothelium-dependent function, assessed non-invasively using the flow-mediated dilation (FMD) method; (2) arterial blood gas analysis. Other baseline evaluations included clinical and anthropometric data, and laboratory tests.

RESULTS

The total group showed a significant improvement in FMD as a result of NIV effect (P = 0.010). While arterial carbon dioxide and oxygen were not altered, oxygen saturation increased after NIV (P = 0.045). The subgroup comparison of responders (FMD ≥ 1%) and non-responders (FMD < 1%) showed significant baseline differences in body mass index (BMI) (P = 0.019) and predicted forced expiratory volume in one second (FEV₁) (P = 0.007). In univariate and multivariate analyses, both BMI and FEV₁ were determinant for endothelial response to NIV.

CONCLUSION

NIV acutely improves endothelial function in hospitalized AECOPD patients. Overweight and COPD severity may represent important characteristics for the magnitude of peripheral vascular response.

Acute effect of inhaled iloprost on exercise dynamic hyperinflation in COPD patients: A randomized crossover study

BACKGROUND AND OBJECTIVE

We tested whether the prostacyclin analog inhaled iloprost modulates dead space, dynamic hyperinflation (DH), and systemic inflammation/oxidative stress during maximal exercise in subjects with chronic obstructive pulmonary disease (COPD) who were not selected based on pulmonary hypertension (PH).

METHODS

Twenty-four COPD patients with moderate-severe obstruction (age 59 ± 7 years, FEV₁ 53 ± 13% predicted) participated in a randomized, double-blind, placebo-controlled crossover trial. Each subject received a single nebulized dose of 5.0 μg iloprost or placebo on non-consecutive days followed by maximal cardiopulmonary exercise tests. The primary outcome was DH quantified by end-expiratory lung volume/total lung capacity ratio (EELV/TLC) at metabolic isotime.

RESULTS

Inhaled iloprost was well-tolerated and reduced submaximal alveolar dead-space fraction but did not significantly reduce DH (0.70 ± 0.09 vs 0.69 ± 0.07 following placebo and iloprost, respectively, p = 0.38). Maximal exercise time (9.1 ± 2.3 vs 9.3 ± 2.2 min, p = 0.31) and peak oxygen uptake (17.4 ± 6.3 vs 17.9 ± 6.9 mL/kg/min, p = 0.30) were not significantly different following placebo versus iloprost.

CONCLUSIONS

A single dose of inhaled iloprost was safe and reduced alveolar dead space fraction; however, it was not efficacious in modulating DH or improving exercise capacity in COPD patients who were not selected for the presence of PH.

Non-Invasive Ventilation as an Adjunct to Exercise Training in Chronic Ventilatory Failure: A Narrative Review

BACKGROUND

Chronic ventilatory failure (CVF) may be associated with reduced exercise capacity. Long-term non-invasive ventilation (NIV) may reduce patients' symptoms, improve health-related quality of life and reduce mortality and hospitalisations. There is an increasing use of NIV during exercise training with the purpose to train patients at intensity levels higher than allowed by their pathophysiological conditions.

OBJECTIVE

This narrative review describes the possibility to train patients with CVF and NIV use as a tool to increase the benefits of exercise training.

METHODS

We searched papers published between 1985 and 2018 in (or with the summary in) English language in PubMed and Scopus databases using the keywords "chronic respiratory failure AND exercise," "non invasive ventilation AND exercise," "pulmonary rehabilitation" and "exercise training."

RESULTS

Exercise training is feasible and effective also in patients with CVF. Assisted ventilation can improve exercise tolerance in different clinical conditions. In patients under long-term home ventilatory support, NIV administered also during walking results in improved oxygenation, decreased dyspnoea and increased walking distance. Continuous positive airway pressure and different modalities of assisted ventilation have been delivered through different interfaces during exercise training programmes. Patients with CVF on long-term NIV may benefit from exercising with the same ventilators, interfaces and settings as used at home.

CONCLUSION

We need more randomised clinical trials to investigate the effects of NIV on exercise training in patients with CVF and define organisation and setting.

The Use of Non-invasive Ventilation during Exercise Training in COPD Patients

Non-invasive ventilation (NIV) is increasingly used in addition to exercise training in patients with chronic obstructive pulmonary disease with the purpose to allow them to train at higher intensities. Different modalities of assisted ventilation have been used with benefits for relief of dyspnoea and increase in exercise capacity. Nevertheless there are some potential problems with the use of NIV in pulmonary rehabilitation programmes. Despite promising results, a generalised use of NIV during exercise training programmes is unlikely to have a role in routine settings. The use of NIV during exercise training as a component of pulmonary rehabilitation should be reserved to individual cases.

Non invasive ventilation as an additional tool for exercise training

Recently, there has been increasing interest in the use of non invasive ventilation (NIV) to increase exercise capacity. In individuals with COPD, NIV during exercise reduces dyspnoea and increases exercise tolerance. Different modalities of mechanical ventilation have been used non-invasively as a tool to increase exercise tolerance in COPD, heart failure and lung and thoracic restrictive diseases. Inspiratory support provides symptomatic benefit by unloading the ventilatory muscles, whereas Continuous Positive Airway Pressure (CPAP) counterbalances the intrinsic positive end-expiratory pressure in COPD patients. Severe stable COPD patients undergoing home nocturnal NIV and daytime exercise training showed some benefits. Furthermore, it has been reported that in chronic hypercapnic COPD under long-term ventilatory support, NIV can also be administered during walking. Despite these results, the role of NIV as a routine component of pulmonary rehabilitation is still to be defined.