The Influence of Dialysate Exchange on Cardiac Output in CAPD Patients

Abstract

The influence of a peritoneal dialysate exchange on cardiac output (CO) in the setting of continuous ambulatory peritoneal dialysis (CAPD), was studied in 12 patients before, during and between two consecutive exchanges. The two exchanges only differed in that, during the second exchange, the patients were more dehydrated because fluid intake was forbidden during the study -mean sum of volume loss between the two exchanges: 319 ± 86 ml/min. During the first exchange, neither removal and instillation of dialysate resulted in significant hemodynamic alterations. During the second exchange, the removal of dialysate resulted in an increase of CO (from 5.7 ± 0.4 l/min to 6.2 ± 0.5 l/min, p < 0.05) and the instillation of fresh dialysate in a decrease of CO (from 6.2 ± 0.5 l/min to 5.8 ± 0.5 l/min, p < 0.05). It is concluded that, in the setting of CAPD, a dialysate exchange does not result in significant hemodynamic alterations, unless the patient's fluid intake has been restricted. Furthermore, the hemodynamic alterations were not more pronounced in those patients with low body weight, despite the use of the same dialysate volume.