Respiratory symptoms were associated with low CdynL and high RfL, both at rest and exercise (Table 1). Patients with a history of two years or more had at maximal work lower CdynL than those with shorter duration of disease (55 percent pred and 74 percent pred, respectively, p<0.001), and higher RfL (224 percent pred and 146 percent pred, respectively, p<0.05).
No significant differences were seen between patients over 40 and the younger ones, smokers and exsmokers vs nonsmokers or between treated and untreated individuals. buy ventolin inhalers
Arterial Blood Gases in All Patients and in Clinical Subgroups
Both PaC02 and Pa02 were reduced at rest and during exercise (Table 1). No patient had abnormally high PaC02 at rest or during exercise. The Pa02 at rest in the supine position was below the normal range in 22 subjects, and in 20 in the sitting position. Figure 2 shows that both normalization of Pa02 with exercise, and deterioration with falling Pa02, occurred.
Older patients had lower PaOz at maximal exercise than the younger ones (p<0.01), ie, PaO£ was 9.7 kPa and 10.9 kPa, respectively (both p<0.001), and lower sum of Pa02 and PaC02 at exercise (p<0.01). The sum was 14.2 kPa and 15.2 kPa, respectively (both p<0.001).
Figure 2. The change in PaO, during exercise is shown in those patients who have an abnormal PaO, at rest and/or at maximal work. The PaO* is given in kPa. The end points are PaO, sitting at rest and at maximal work expressed as the working capacity in percentage of the predicted normal value. The dots indicate an abnormal value of PaO,. a, upper: These patients had unchanged or rising PaO* during exercise though the resting value was abnormal, b, lower. In other patients there was a fall in PaO* during exercise irrespective of normal or abnormal PaOz at rest.