ABSTRACT
Hospital Antwerp, Antwerp, Belgium 22.1 INTRODUCTION Children with end-stage renal disease (ESRD) are characterized by multiple factors that influence their exercise capacity like anaemia, metabolic acidosis, electrolyte imbalance, osteopenia, growth failure, malnutrition, fluid imbalance, muscle wasting and a sedentary life style (Bar-Or and Rowland, 2004, Painter et al., 2007). Increased exercise capacity ( 2peak) was reported in adult and pediatric dialysis patients after treatment for anemia using erythropoietin (Robertson et al., 1990; Warady et al., 1991), although the 2peak response to increasing hematocrit in patients on dialysis was clearly blunted compared with healthy subjects (Painter, 2008); suggesting an impairment in oxygen extraction at the muscle tissue level. Matsumoto et al. (2006) observed indications for an impaired mitochondrial oxygen consumption and a reduced oxygen delivery to the muscle in patients with ESRD using Near Infrared Spectroscopy (NIRS). The objective of this study was to evaluate the cardiopulmonary exercise test (CPET) results in children with ESRD and compare their results with those of children with an acquired myopathy. 22.2 METHODS Patients (13 boys and 7 girls; mean age 14.1±3.4 years) on dialysis (11 haemodialysis and 9 peritoneal dialysis) from four paediatric dialysis centres participated in this study. Their characteristics are described previously (Takken et al., 2009). CPET was performed using a graded exercise test on a cycle ergometer (Lode Corrival pediatric) and a calibrated respiratory gas-analysis system (Cortex
MetaMax) to determine oxygen uptake ( 2peak), carbondioxide production (
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