conclusions negative pressure inspiration is significantly impaired by an unstable chest wall. restoring mechanical stability of the fractured ribs improves respiratory outcomes similar to baseline values. results a wide variation in the mean inspiratory volumes and peak flows were measured between specimens; however, the effect of a flail chest wall and the subsequent internal fixation of the ...

BACKGROUND The 2005 American Thoracic Society/European Respiratory Society guidelines on spirometry emphasize examination of the inspiratory curve of the flow-volume loop for evidence of intrathoracic or extrathoracic upper airway obstruction. We sought to determine how frequently evaluations are performed for abnormal inspiratory curves. METHODS We retrospectively reviewed all examinations p...

BACKGROUND A lung-protecting strategy is essential when ventilating acute lung injury/acute respiratory distress syndrome patients. Current emphasis is on limiting inspiratory pressure and volume. This study was designed to investigate the effect of peak inspiratory flow on lung injury. METHODS Twenty-four rabbits were anesthetized, tracheostomized, ventilated with a Siemens Servo 300, and ra...

We measured the tidal volume achieved during intermittent positive pressure ventilation using various inspiratory times with a minimum of 0.2 seconds. Results indicate that tidal volume shows no reduction with inspiratory times down to 0.4 seconds. An inspiratory time of 0.3 seconds, however, is likely to reduce tidal volume by 8%, and at 0.2 seconds a 22% fall may be anticipated.

Chest wall volumes and breathing patterns of 13 male COPD patients were evaluated at rest and during inspiratory loaded breathing (ILB). The sternocleidomastoid (SMM) and abdominal muscle activity was also evaluated. The main compartment responsible for the tidal volume at rest and during ILB was the abdomen. During ILB patients exhibited, in addition to increases in the ratio of inspiratory ti...

The physiology underlying inspiratory flow has been the subject of study for a long time. In the late 1950s, Hyatt et al did seminal investigations of the pressure, flow, and volume characteristics of the lung.1 In those early days the primary interest in flow-volume curves centered on expiratory flow, what controlled it, and how it was limited in various obstructive lung diseases.2 Even in the...

BACKGROUND Chest wall mobility is often measured in clinical practice, but the correlations between chest wall mobility and respiratory muscle strength and lung volumes are unknown. We investigate the associations between chest wall mobility, axillary and thoracic cirtometry values, respiratory muscle strength (maximum inspiratory pressure and maximum expiratory pressure), and lung volumes (exp...

Slow spirometry and forced spirometry (flow volume loop) are often used to measure clinically relevant lung volumes and forced expiratory and inspiratory flows. Dynamic parameters, such as forced expiratory volumes in one second (FEV1) or forced vital capacity (FVC) and static lung volumes, such as expiratory reserve volume (ERV), inspiratory capacity (IC) and inspiratory vital capacity (IVC) c...

BACKGROUND This study investigated whether the inspiratory muscles are susceptible to fatigue during acute airway narrowing because of increased airway resistance and hyperinflation. METHODS Asthmatic subjects performed up to four series (on separate days) of 18 maximal static inspiratory efforts of 10 seconds' duration with 10 second rest intervals (50% duty cycle; total duration six minutes...