title: Accuracy of noninvasive estimates of respiratory muscle effort during spontaneous breathing in restrictive diseases.
abstract: Mean inspiratory pressure (Pi), estimated from the occlusion pressure at the mouth and the inspiratory time, is useful as a noninvasive estimate of respiratory muscle effort during spontaneous breathing in normal subjects and patients with chronic obstructive pulmonary disease. The aim of this study was to compare the Pi with respect to mean esophageal pressure (Pes) in patients with restrictive disorders. Eleven healthy volunteers, 12 patients with chest wall disease, 14 patients with usual interstitial pneumonia, and 17 patients with neuromuscular diseases were studied. Pi, Pes, and mean transdiaphragmatic pressure were simultaneously measured. Tension-time indexes of diaphragm (TTdi) and inspiratory muscles (TTmu) were also determined. In neuromuscular patients, significant correlations were found between Pi and Pes, Pi and transdiaphragmatic pressure, and TTmu and TTdi. A moderate agreement between Pi and Pes and between TTmu and TTdi was found. No significant correlation between these parameters was found in the other patient groups. These findings suggest that Pi is a good surrogate for the invasive measurement of respiratory muscle effort during spontaneous breathing in neuromuscular patients.
authors.affiliation: Alfredo Marqueriáe 11, izqda, 1 degrees A, 28034 Madrid, Spain. fgr01m@jazzfree.com
authors.forename: Francisco
authors.initials: F
authors.lastname: García-Río
authors.forename: José M
authors.initials: JM
authors.lastname: Pino
authors.forename: Angeles
authors.initials: A
authors.lastname: Ruiz
authors.forename: Salvador
authors.initials: S
authors.lastname: Díaz
authors.forename: Concepción
authors.initials: C
authors.lastname: Prados
authors.forename: José
authors.initials: J
authors.lastname: Villamor
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D003964:Diaphragm / Q000503:physiopathology; D004947:Esophagus / Q000503:physiopathology; D006801:Humans; D001239:Inhalation; D017563:Lung Diseases, Interstitial / Q000503:physiopathology*; D008875:Middle Aged; D009468:Neuromuscular Diseases / Q000503:physiopathology*; D011312:Pressure; D012119:Respiration; D012129:Respiratory Function Tests / Q000592:standards*; D012132:Respiratory Muscles / Q000503:physiopathology*; D013896:Thoracic Diseases / Q000503:physiopathology*