The authors devised a new treatment strategy using continuous ambulatory hemofiltration (CAHF) in between short hemodialyses (short HD). For CAHF, a small wearable hemofilter (0.1 m2) was developed using a membrane permeable to low molecular weight proteins. During short HD, no body water was removed, but saline, equivalent to 3% body weight, was administered at a constant rate. During CAHF, 1 L of replacement fluid was administered intravenously after every meal to increase the replacement volume. Switch from the conventional to new strategy resulted in far more stable blood pressure during short HD, a decrease in time averaged body weight, and a decrease in a decrease in time averaged blood urea nitrogen and plasma beta 2-m levels.