Pulmonary ventilation

Since 1956, the pMDI has become the most commonly prescribed and used aerosol device in the world. While concerns about global warming have led to a worldwide ban of CFCs, new HFA-propelled pMDIs are in development, requiring an evolutionary transition in the technology. The phase-out of CFC-propelled pMDIs has stimulated the development of more efficient DPIs, but issues such as cost of device production, inspiratory flow requirement, and the effects of ambient humidity on drug delivery may limit DPI acceptance, and industry projections suggest that the DPI will not completely replace the pMDI. Holding chambers may perform differently with HFA-propelled pMDIs, but HFA-propelled pMDIs generally appear to cause less oropharyngeal deposition and to improve lung delivery while continuing to provide protection from poor hand-breath coordination. The initial offerings of the emerging HFA-propelled pMDI technology appear to be resulting in an improved pMDI.

Pulmonary function is altered in ankylosing spondylitis (AS) owing mainly to the restriction of chest wall involvement (limited chest expansion). The objective of this study was to investigate the relationship between chest expansion, respiratory muscle strength (MIP, MEP) maximum voluntary ventilation (MVV), and BASFI score in patients with AS. Twenty-three male patients with definite AS and 21 age-matched healthy male controls were recruited for the study. Patients with AS were assessed for functional status by BASFI. Measurement of chest expansion and lumbar spinal flexion (modified Schober) method was performed in all subjects. Pulmonary function tests were performed by spirometry. Respiratory muscle strength was evaluated by a mouth-pressure meter (MPM). Body mass index (kg/m2) was recorded in all individuals. Chest expansion and modified Schober measurement were significantly lower in AS patients (p<0.05). Pulmonary function tests revealed restrictive lung disease. The mean BASFI score suggested good functional capacity in the AS group. The respiratory muscle strength and MVV were also lower in AS (p<0.05). The chest expansion was correlated with MIP and MEP values (r=0.491; p=0.02, r=0.436; p=0.05). Chest expansion was also correlated negatively with disease duration (r=−0.502; p=0.03). In addition, there was no correlation between chest expansion and BASFI score (r=−0.076; p=0.773). This study demonstrates that functional status (BASFI) is not influenced by the limitation of chest wall movement. It may be as a result of the maintenance of moderate physical activity during active life in patients with AS.

This study was designed to quantify the daily distribution of training intensity in a group of professional soccer players in Norway based on three different methods of training intensity quantification. Fifteen male athletes (age, 24 ± 5 y) performed treadmill test to exhaustion to determine heart rate and VO2 corresponding to ventilatory thresholds (VT1, VT2), maximal oxygen consumption (VO2max) and maximal heart rate. VT1 and VT2 were used to delineate three intensity zones based on heart rate. During a 4 wk period in the preseason (N = 15), and two separate weeks late in the season (N = 11), all endurance and on-ball training sessions (preseason: N = 378, season: N= 78) were quantified using continuous heart rate registration and session rating of perceived exertion (sRPE). Three different methods were used to quantify the intensity distribution: time in zone, session goal and sRPE. Intensity distributions across all sessions were similar when based on session goal or by sRPE. H...