title: Exercise related ventilation dynamics and clinical correlates in patients with fibrotic idiopathic interstitial pneumonias.
abstract: Assessment of exercise performance is a key component in the management of interstitial lung diseases, as its limitation may occur very early. Aim of the present study was to assess ventilation dynamics in combination with pulse-oximetry changes in 54 clinically stable patients affected by idiopathic pulmonary fibrosis or idiopathic fibrotic nonspecific interstitial pneumonia. Testing was successfully performed with the Spiropalm 6-MWT Hand-held spirometer by the majority of cases (94%). End test oxygen saturation (SpO2) values <88% were common in most of patients (76%), with a mean distance walked of 403 meters. Ventilation significantly increased due to the contribution of the tidal volume and the respiratory frequency (RF). This finding was associated with a decrease of the end of test respiratory reserve (RR), that was <20% in 9 cases (17.6%). Lung function was inversely related to the end of test RF, while a positive correlation occurred with the end of test RR and the estimated maximal voluntary ventilation (MVV). RR was also a predictive factor of declining forced vital capacity and lung diffusion capacity for carbon monoxide (DLCO) over a 6-month period. Further factors of DLCO impairment were low SpO2 and MVV. Comparison with the cardio-pulmonary exercise test (CPET) showed that the 6-MWT end of test RR was inversely related to the CPET-derived peak RF and VE/VCO2 suggesting RR as pivotal in exercise limitation assessment. Our results open challenging perspectives in an unexplored field. Future research will include management of latent respiratory failure and monitoring of disease progression and therapy response.
authors.affiliation: . demartinomarina@yahoo.it.
authors.forename: Marina
authors.initials: M
authors.lastname: De Martino
authors.forename: Raffaele
authors.initials: R
authors.lastname: Cobuccio
authors.forename: Dario
authors.initials: D
authors.lastname: Bruzzese
authors.forename: Gaetano
authors.initials: G
authors.lastname: Rea
authors.forename: Ilernando
authors.initials: I
authors.lastname: Meoli
authors.forename: Francesco
authors.initials: F
authors.lastname: Stefanelli
authors.forename: Angelo
authors.initials: A
authors.lastname: Canora
authors.forename: Annalisa
authors.initials: A
authors.lastname: Capaccio
authors.forename: Alessandro
authors.initials: A
authors.lastname: Sanduzzi
authors.forename: Alessandro
authors.initials: A
authors.lastname: Matarese
authors.forename: Marialuisa
authors.initials: M
authors.lastname: Bocchino
mesh_terms: D000368:Aged; D018450:Disease Progression; D005080:Exercise Test; D017079:Exercise Tolerance; D005260:Female; D006801:Humans; D054988:Idiopathic Interstitial Pneumonias / Q000175:diagnosis / Q000503:physiopathology*; D054990:Idiopathic Pulmonary Fibrosis / Q000175:diagnosis / Q000503:physiopathology*; D008168:Lung / Q000503:physiopathology*; D008297:Male; D008451:Maximal Voluntary Ventilation; D008875:Middle Aged; D010092:Oximetry; D011237:Predictive Value of Tests; D011379:Prognosis; D011653:Pulmonary Diffusing Capacity; D012123:Pulmonary Ventilation; D015656:Respiratory Mechanics; D013147:Spirometry; D013990:Tidal Volume; D013997:Time Factors
keywords: 6 minute walk test, fibrotic idiopathic interstitial pneumonias, ventilation, cardio-pulmonary exercise testing, exercise limitation