Breathing control, brain, and bodily self-consciousness: Toward immersive digiceuticals to alleviate respiratory suffering

Impact des processus cognitifs sur la ventilation spontanée et en condition de dyspnée expérimentale

See related article Both static and dynamic hyperinflation (DH) are known to play a key role in dyspnoea sensation and exercise capacity limitation in chronic obstructive pulmonary disease (COPD).1, 2 DH is defined as a temporary increase in end-expiratory lung volume relative to the resting baseline value when ventilation is acutely increased, and can be quantified as a reduction in inspiratory capacity from baseline or resting state.1 Bronchoscopic lung volume reduction (BLVR) techniques are aimed at reducing lung hyperinflation, which in the case of endobronchial valve (EBV) treatment is achieved by placing these valves in the supporting segmental airways of a preselected target emphysematous lobe, resulting in a lobar atelectasis.3 All randomized clinical trials investigating EBV have reported a significant reduction of static hyperinflation after treatment.4-8 While static hyperinflation is considered as an essential outcome measure after EBV treatment, there are only limited clinical data available regarding the effect of lung volume reduction treatment on DH. Two studies, performed in patients with emphysema who underwent lung volume reduction surgery, observed a reduction in DH after treatment.9, 10 In two studies investigating the effect of BLVR on DH, one study observed a reduction in DH while another observed an increase in DH after treatment, the latter due to a significant improvement in static hyperinflation, allowing a larger change in inspiratory capacity during the DH manoeuvre.11, 12 In a recent publication in Respirology, Fumat et al.13 report the outcomes of their multi-centre clinical study investigating the effect of BLVR with EBVs on DH. They included 39 patients who were treated with EBV and underwent incremental cycle ergometry at baseline and 3 months after treatment. After treatment, a significant improvement in inspiratory capacity at isotime was observed, with approximately half of the patients reaching the minimal important difference (MID) criteria for reduction of DH. This well executed study provides relevant new data to the field of BLVR. Fumat et al. raise the question whether patients suffering from relevant DH but with static hyperinflation lower than the currently accepted treatment selection threshold of residual volume (RV) 175% of predicted or RV/total lung capacity ratio of >55% could be clinical responders after EBV treatment.3 While this is indeed an interesting subject for future research, it is very well possible that only a limited number of patients might meet these criteria. It could be debated whether the assessment of DH deserves a standard role in patient selection for and assessment of treatment response after BLVR treatment. While the current study does provide useful further insights in the mechanisms of effect of EBV treatment, no significant differences were observed in modified Medical Research Council (mMRC) scores and 6-minute walking distance (6MWD) between DH responders and non-responders. We therefore wonder to what degree DH actually contributes to these important patient-based outcomes. Future studies in patients treated with EBV, with a larger magnitude of response and higher number of responders, are needed to further elucidate this. When the presence or magnitude of DH indeed does not identify responders, we would favour the use of outcome measures that are closer to patients’ experiences, such as attainment of patient-specific goals, quality of life outcomes and assessment of exercise capacity.14 In conclusion, the current study demonstrated a significant reduction of DH after EBV treatment. While assessment of DH provides useful insights in the mechanisms of effect of EBV treatment, we propose to prioritize other outcome measures closer to patient experiences after BLVR. Jorrit B. A. Welling: No conflicts of interests. Dirk-Jan Slebos: Principal Investigator and advisor to PulmonX Inc., CA, USA. This publication is linked to a related article. To view this article, visit https://doi.org/10.1111/resp.14488 

https://onlinelibrary.wiley.com/doi/pdfdirect/10.1111/resp.14507

Dynamics of hyperinflation

Réduction de volume pulmonaire par valves endobronchiques : une nouvelle approche

In healthy humans, inspiratory threshold loading deteriorates cognitive performances. This can result from motor-cognitive interference (activation of motor respiratory-related cortical networks vs...

Impact of inspiratory threshold loading on brain activity and cognitive performances in healthy humans.

Dynamic hyperinflation (DH) is a major marker of exertional dyspnoea in severe emphysema. We hypothesized that bronchoscopic lung volume reduction (BLVR) using endobronchial valves (EBVs) decreases DH.

Impact of bronchoscopic lung volume reduction with endobronchial valves on dynamic hyperinflation: Results from the PIERCE study

Based on the positive outcomes of five randomised controlled trials [1–4], bronchoscopic lung volume reduction (BLVR) using endobronchial valves (Zephyr EBVs; PulmonX Corp., Redwood City, CA, USA) is now a treatment option for a subset of patients with severe emphysema [5]. Very few data are available regarding the relevance of a sequential, bilateral treatment using EBVs in patients with severe emphysema. Fiorelli et al. [6] reported in 2016 their experience with 14 patients treated contralaterally after loss of benefit (18 months median delay between both sides) and demonstrated that patients can recover similar functional parameters compared to outcomes obtained after the initial intervention. The same year, Trudzinski et al. Bilateral endobronchial valves treatment can lead to additional significant benefits in patients who respond to the first procedure and have a clear target lobe on both lungs but increases the rate of complications https://bit.ly/3J0mZ8h

/pdf/bilateral-endobronchial-valves-treatment-for-severe-2ksw28sk.pdf

Romain Barthes

Papers

Impact of inspiratory threshold loading on brain activity and cognitive performances in healthy humans.

Impact of bronchoscopic lung volume reduction with endobronchial valves on dynamic hyperinflation: Results from the PIERCE study

Bilateral endobronchial valves treatment for severe emphysema

Bronchoscopic lung volume reduction with endobronchial valves improves respiratory muscle function in patients with severe emphysema