Effects of ergoreflex on respiration and other efferent effects in adult male patients with chronic obstructive pulmonary disease

Abstract

In COPD, overactivation of ergoreceptors may be a link between peripheral changes, sympathetic over activation and increased hemodynamic and ventilatory responses to exercise. The current study was undertaken to test the hypothesis that, ergoreflex in COPD patients is hyperactive and contributes to breathlessness and exercise limitation. The aim of study was to (1) demonstrate its hyperactivity in COPD (2). To record other efferent effects. Twenty stable COPD male patients aged 50 +/- 2.5 years and twenty healthy male subjects aged 48 +/- 3.5 years were studied under experimental and control groups. The ergoreflex contribution to cardio respiratory parameters was assessed by post-handgrip regional circulatory occlusion method (PH-RCO) and computed as the difference in heart rate and respiratory rate response between PH-RCO and control run without PH-RCO. Results were analyzed for significance between two groups by repeated measures ANOVA. COPD patients showed over activation of ergoreflex as compared to control subjects in terms of heart rate during sustained hand grip (SHG) exercise (117 +/- 1.22 versus 89 +/- 0.89) beats/min, recovery heart rate (p < 0.001), and respiratory rate during SHG (24 +/- 0.54 versus 19 +/- 03.24) breaths/min and recovery respiratory rate (p < 0.001). Degree of overactivation of ergoreflex was significant in COPD patients (p < 0.001). In COPD, overactivity of ergoreflex is associated with abnormal cardio respiratory reflex control. COPD patients showed overactivation of sympathetic nervous system as evidenced by heart rate changes during exercise and delayed recovery.