In nine subjects with chronic obstructive pulmonary disease (COPD) and pulsus paradoxus, M-mode echocardiograms showed inspiratory augmentation of right ventricular dimensions and inspiratory decrease of left ventricular diastolic dimensions. In five subjects in whom the echocardiographic transistor was in the subxiphoid position, mean right ventricular dimensions increased during inspiration f...

Prolonged high-intensity ventilation is associated with the development of rapid shallow breathing with decreased end-inspiratory volumes of all chest wall compartments. During respiratory muscle endurance training using normocapnic hyperpnoea, tidal volume (V(T)) is normally kept constant. The aim of this study was to investigate possible changes in muscle recruitment during constant-V(T) hype...

The factors determining maximum expiratory flow and maximum inspiratory flow of the lung are reviewed with particular reference to a model which compares the lung on forced expiration to a Starling resistor. The theoretical significance of the slope of the expiratory maximum flowvolume curve is discussed. A method of comparing maximum expiratory flow with maximum inspiratory flow at similar lun...

OBJECTIVE To investigate the time-courses of lung function and respiratory muscle pressure generating capacity after spinal cord injury. DESIGN Multi-centre, prospective cohort study. SUBJECTS One hundred and nine subjects with recent, motor complete spinal cord injury. METHODS Lung function and respiratory muscle pressure generating capacity were measured at first mobilization, at discha...

OBJECTIVE To evaluate inspiratory volume in patients undergoing cardiac surgery and to determine the effects that incentive spirometry (IS) and the breath stacking (BS) technique have on the recovery of FVC in such patients. METHODS A prospective, controlled, randomized clinical trial involving 35 patients undergoing cardiac surgery at the Hospital de Força Aérea do Galeão (HFAG, Galeão Air F...

PURPOSES The aim of the study was to use three-dimensional high-resolution CT scan data sets in inspiration and expiration for the quantitative evaluation of emphysema. Using an advanced dedicated semiautomatic analysis tool, the functional inspiratory/expiratory shifts of emphysema volume and clusters were quantified. The pulmonary function test (PFT) served as the clinical "gold standard." ...

Introduction The basic 4 volumes do not overlap each other: tidal volume, inspiratory and expiratory reserve volumes and residual volume. On the other hand, lung capacities include two or more volumes: inspiratory capacity, vital capacity, functional residual capacity and total lung capacity. Spirographic examination of lung functions is characterized by the following main changes: in the obstr...

BACKGROUND High tidal volume can cause ventilator-induced lung injury (VILI), but positive end-expiratory pressure (PEEP) is thought to be protective. We aimed to find the volumetric VILI threshold and see whether PEEP is protective per se or indirectly. METHODS In 76 pigs (22 ± 2 kg), we examined the lower and upper limits (30.9-59.7 mL/kg) of inspiratory capacity by computed tomography (CT)...

Ideally, the inspired (tidal) volume (V(T)) provided by a volume-controlled ventilation device should not change when the pressure imposed on the ventilator varies. A bench study evaluation of V(T) versus pressure was performed on 10 commercially available devices. The difference between the desired V(T) and the observed V(T) reached 100 mL for some devices when inspiratory resistance was at it...

BACKGROUND Esophageal pressure, used as a surrogate for pleural pressure, is commonly measured by air-filled balloon, and the accuracy of measurement depends on the proper balloon volume. It has been found that larger filling volume is required at higher surrounding pressure. In the present study, we determined the balloon pressure-volume relationship in a bench model simulating the pleural cav...