Patent ID: 8496606

Claim:
A method for treating chronic renal disease of a patient comprising: (a) for a duration of at least 4 hours, performing an ultrafiltration process by using a portable treatment device having a membraneless microfluidic channel, said performing including: (a1) passing blood at a flow rate into the membraneless microfluidic channel having dimensions such that, at the blood flow rate, a fraction depleted of cytoplasmic bodies from the blood is generated; (a2) removing a portion of the fraction depleted of cytoplasmic bodies from the membraneless microfluidic channel; (a3) extracting at least water from the removed portion of the fraction depleted of cytoplasmic bodies using a first membrane; and (a4) returning the removed portion of the fraction depleted of cytoplasmic bodies, minus some water, back to the patient; an ultrafiltration rate of the ultrafiltration process resulting in a rate of production of ultrafiltrate of less than 0.4 l/hr; (b) repeating the performing an ultrafiltration process at least daily, the ultrafiltration process requiring no continuous consumption of exogenous fluid; and (c) at a frequency that is less than daily, using another treatment device to perform a renal replacement therapy in which blood components are exchanged between blood and a sorbent or between blood and a substantial supply of exogenous fluid across a second membrane, the blood contacting the second membrane or the sorbent of the another treatment device; the repeating either being done on days in which the performing a renal replacement therapy is done or being skipped on the days in which the performing a renal replacement therapy is done.