Loading

wait a moment

Exercise intolerance in chronic airflow limitation: Variation in the ventilatory responses to exercise (3)

The effects of these three factors on Ve may be expressed in an equation that combines metabolism (oxygen and RER), Va (reflected in PaC02) and dead space:
Exercise intolerance. Formula
which helps us to understand why Ve may be so variable among different individuals during exercise. Increases in VE contribute as much to dyspnea in COLD as reductions in MVV (Figure 5).
Figure 5. Exercise intolerance
Figure 5) Ventilation in relation to carbon dioxide output in the same patients as in Figure 4; ventilation in exercise progressively encroached on maximal voluntary ventilation (MW) with progressive dyspnea, due to both increases in ventilation and reductions in MW. Ve Volume of expired gas
Different types of COLD syndromes: Soon after I became a registrar in chest medicine at the Hammersmith in 1961,1 was drawn into discussions regarding clinical and physiological differences between patients with chronic airflow obstruction who were ‘pink and puffing’ with evidence of emphysema, and those who were ‘blue and bloated’ and often did not show any emphysema physiologically or post mortem. Striking in this comparison was a difference in dyspnea and exercise limitation, both of which were much increased in the ‘puffers’ (type A); the ‘bloaters’ (type B), on the other hand, could often exercise surprisingly well, in the face of chronic hypercapnia, hypoxemia and right heart ‘failure’. In spite of the work of Christie and his team showing that emphysema was associated with loss of elasticity and severe gas exchange impairment, the limiting factor at the time was thought to be mainly airflow obstruction as reflected in reductions in FEVi. But differences in FEVi did not explain differences among patients in exercise capacity and dyspnea, and the thought arose that one could only discover the factors behind this variability by actually studying what happened during exercise. Take advantage of this chance to find vardenafil online pharmacy and save quite some money.

Leave a Reply

Your email address will not be published. Required fields are marked *