Key clinical point: Inhibiting the carotid chemoreceptor (CC) – which appears to play a role during exercise in patients with chronic obstructive pulmonary disorder (COPD) – doesn’t affect exercise tolerance.
Major finding: After 4 minutes of exercise at 75% peak power output, inhibition of CC had no effect on ventilation, operating volumes, or dyspnea in patients with COPD.
Study details: Randomized, double-blind, placebo-controlled crossover exercise testing of 12 patients with mild-moderate COPD (mean age = 67) and 12 age- and gender-matched healthy controls (mean age = 63). Some received intravenous saline while others received low-dose dopamine to inhibit CC levels.
Disclosures: The Canadian Institutes of Health Research funded the study. One author discloses support from a graduate scholarship from the Lung Association of Alberta/Northwest Territories, and another discloses support from the Motyl Endowment Studentship in Cardiac Sciences. No other disclosures are reported.
Phillips DB et al. Respir Med. 2019(160):105815.