AbstractThe current thesis investigated the acute physiological response to exercise in end-stage renal disease (ESRD), with the intention of informing evidence-based exercise prescription guidelines and future research directions. Specifically, cardiovascular haemodynamics, and ventilatory gas exchange were measured during submaximal inter-dialytic (non-haemodialysis days) and intra-dialytic cycling (during haemodialysis). A single group of 20 ESRD patients provided data for three separate experimental chapters: 1) comparison of the acute physiological response to maximal and submaximal exercise in ESRD and healthy participants, 2) comparison of the acute physiological response to standard haemodialysis, and submaximal inter-dialytic and intra-dialytic exercise and, finally 3) comparison of cardiac function during standard haemodialysis and intra-dialytic exercise.
A number of novel cardiovascular, haemodynamic and ventilatory gas exchange responses were identified. Most notably, intra-dialytic exercise acutely reduced regional wall motion abnormalities (indicative of reduced cardiac stunning) compared to standard haemodialysis. Secondly, chronotropic incompetence related to deranged cardiovascular responses to submaximal exercise in ESRD compared to healthy participants. Thirdly, hypoxia during haemodialysis, as evidenced by abnormal arterial-venous O2 difference, minute ventilation, cardiac output and respiratory exchange ratio, contributed to an abnormal physiological response to intra-dialytic exercise compared with inter-dialytic exercise.
These data proposea novel therapeutic role of intra-dialytic exercise in the acute reduction ofmyocardial stunning during haemodialysis. Collectively, data from this thesishave identified causes of reduced aerobic capacity in ESRD, and the acuteeffect of haemodialysis on the ability to perform exercise. It is likely thatappropriately prescribed, evidence-based exercise rehabilitation can be safeand effective in ESRD. Based on the current findings, moderate intensityinter-dialytic and intra-dialytic aerobic exercise should be advocated in ESRD.
|Date of Award||Apr 2020|
|Supervisor||Gordon McGregor (Supervisor), Elizabeth Horton (Supervisor), Derek Renshaw (Supervisor) & Alfonso Jimenez (Supervisor)|