The rate of energy transfer at a specific moment is Pl* V. The average of this product over a number of complete breaths represents the resistive work of breathing. “Functional lung resistance” was defined as the relationship between work rate against resistance and ventilation according to principles described by Otis et al, and represents a flow weighted average of resistance over the whole breath.
RfL = (WresL/VE2) ~ir Eq 1
Ventilation at maximal exercise was related to maximal breathing capacity to yield the dyspneic index, which has a normal range of 60 to 80 percent. flovent inhaler
Arterial blood was obtained from a catheter in a radial artery for immediate analysis of arterial oxygen and carbon dioxide tensions and base excess. Samples were drawn at rest with the patient in both supine and sitting position, and during exercise. The ECC, heart rate, and breathing frequency were also recorded. All subjects had given informed consent to the measurements.
Statistical Methods For statistical analysis, Students f-test for paired and unpaired comparisons and single and double correlation tests were used. Differences with a probability level of p<0.05 are marked *, of p<0.01 ** and of p<0.001 ***. The range of a parameter was calculated as the interval between the fifth and 95th percentiles of observed values.