Introduction
Very few data are available regarding the impact of bronchoscopic lung volume reduction (BLVR) on respiratory muscles function. We aimed at evaluating the evolution of maximal inspiratory pressure (MIP), maximal expiratory pressure (MEP) and sniff nasal inspiratory pressure (SNIP) after BLVR using endobronchial valves (EBVs).
Methods
In this bicentric (Limoges and Toulouse Hospitals) prospective study, we analysed the mean changes of maximal inspiratory pression (MIP), maximal expiratory pression (MEP) and sniff nasal inspiratory pressure (SNIP) at 3 months after treatment. Target lobe volume reduction (TLVR), and changes in forced expiratory (FEV1), residual volume (RV), 6-minute walk distance (6-MWD), mMRC were also calculated.
Results
29 patients were included. TLVR was 1042 ml (63% TLVR, p<0,001), resulting in an 830 ml RV decrease (p=0.006) and a subsequent 215 ml improvement in FEV1 (25% gain, p=0.007). 6MWD was improved by 40 m (p=0.09). MIP significantly improved (83 cm H2O to 106 cm H2O; 28% increase, p=0.01), but not MEP (101 cm H2O to 115 cm H2O, 14% increase, p=0.2) and SNIP (5.6 to 6.4 cm H2O, 14% increase, p=0.18). Increases in MIP and MEP were correlated with RV decrease and FEV1 improvement (R=0.49; p=0.011; and R=0.44, p=0.026, respectively).
Conclusion
BLVR using EBVs improves inspiratory muscles? function, and this improvement is correlated with RV decrease and FEV1 gain.