A method and system for adaptively controlled withdrawal/infusion of a fluid, such as blood, to or from a fluid source, such as a blood vessel. An adaptive flow rate limit is established and periodically adjusted during the course of withdrawal/infusion so as to maximize and optimize the withdrawal/infusion...http://www.google.de/patents/US5178603?utm_source=gb-gplus-sharePatent US5178603 - Blood extraction and reinfusion flow control system and method
