Individualization of Exchange Volume

Abstract

This paper deals with adjustment of instillation volumes to achieve the best efficiency of dialysis in individual patients. Larger volumes may permit fewer daily exchanges which in turn decreases the number of connections and the risk of peritonitis. Factors associated with poor tolerance to increased volumes are discussed. Taller and heavier patients tolerate high volume dialysis better. It is generally accepted that most patients treated with continuous ambulatory peritoneal dialysis (CAPD) require an integrated (renal and dialysis) small molecule clearance of at least ten liters/day (7 ml/min). If dialysate concentration of small molecules equals that of plasma, a peritoneal dialysis clearance is tantamount to daily drainage volume. However, a wide variation in mass transfer has been observed among patients. Although this variation is more pronounced for large molecular weight solutes, the variation is also clinically significant for small molecules (1). In patients with small molecule dialysate concentration lower than that in plasma. the daily peritoneal clearance of ten liters can be achieved with dialysate flow rate exceeding this value and higher than ten liter drainage volumes per day may be required in some anuric patients.