The importance of an extra hour of cycler therapy to obtain better adequacy

As continuous ambulatory peritoneal dialysis (CAPD) patients lose residual renal function, it frequently becomes impossible from them to obtain adequate dialysis unless the dialysis prescription is changed. Increasing the dwell volumes, increasing the frequency of exchanges, and using a night-exchange device or a cycler are the means available to improve adequacy. In an effort to obtain dialysis adequacy, we studied how an extra hour on cycler therapy can contribute to improving dialysis adequacy. Over 18 months, we optimized solute clearance using the PD Adequest program (Baxter Healthcare Corporation, Chicago, Illinois, U.S.A.) in 70 patients. After finding the best total cycler volume, we compared the weekly creatinine clearance and weekly Kt/V from 8-hour cycler therapy to that from 9-hour cycler therapy for the four types of membrane transport. Adding one extra hour on cycler therapy improved weekly creatinine clearance by 3-6.5 L and the weekly Kt/V by 0.16-0.20. When patients are marginally approaching the required weekly Kt/V or creatinine clearance, an extra hour on the cycler may help to achieve the desired adequacy.