Automatic priming technique

A method for treating blood from a patient extracorporeally by a treatment which transfers matter to or from the blood through a semipermeable membrane, the semipermeable membrane being part of a filtration unit of an apparatus and dividing the filtration unit into a primary chamber and a secondary chamber, the primary chamber receiving the blood and the matter transferred across the semipermeable membrane into the blood, the secondary chamber receiving the matter to be transferred into the blood and the matter transferred across the semipermeable membrane from the blood, said method comprising the steps of:

• establishing an extracorporeal blood flow primary circuit from the patient through the primary chamber and back to the patient;
• controlling the flow of blood through the primary circuit;
• selectively supplying a replacement fluid to the blood in the primary circuit prior to returning the blood to the patient;
• controlling the amount of the replacement fluid supplied to the blood in the primary circuit;
• establishing a secondary circuit for the flow of fluid through the secondary chamber;
• selectively supplying a one of a secondary fluid containing matter which is to be transferred across the semipermeable membrane into the blood or a secondary fluid to remove matter from the secondary chamber which has been transferred across the semipermeable membrane from the blood to the secondary chamber;
• controlling the amount of secondary fluid supplied to the secondary chamber;
• collecting fluid exiting from the secondary chamber;
• controlling the amount of fluid collected from the secondary chamber;
• selecting one of a plurality of different extracorporeal blood treatments to be performed by the apparatus;
• automatically moving a priming fluid into the primary and secondary circuits prior to treatment according to the extracorporeal blood treatment selected, fully priming portions of the primary and secondary circuits to be used during the selected treatment and partially filling with priming fluid those portions of the primary and secondary circuits not to be used during the selected treatment;
• initiating the selected treatment;
• automatically controlling the rate of flow of fluid through the primary circuit, the rate of flow of replacement fluid into the primary circuit, the rate of flow of secondary fluid into the secondary chamber and the rate of flow of fluid collected from the secondary chamber according to the extracorporeal blood treatment selected;
• and
• storing information defining which of the ones of the replacement fluid and the secondary fluid are to be supplied for each of the plurality of treatments.

Method for controlling and monitoring the circulation of body fluids and medical fluids through a circuit for multiple blood extracorporeal treatments, said circuit comprising:

• a filtration unit having a primary and a secondary chamber separated by a semipermeable membrane, each chamber having an inlet and an outlet;
• a primary circuit comprising a blood access line connected to the inlet of the primary chamber and a blood return line connected to the outlet of the primary chamber;
• a secondary circuit comprising a secondary fluid line connected to the inlet of the secondary chamber and a collection fluid line connected to the outlet of the secondary chamber;
• a replacement fluid line connected to the primary circuit;
• an anticoagulant fluid line connected to the blood access line;
• and
• memory for storing preprogrammed information selected from the group consisting of preprogrammed priming fluid instructions, priming protocols, and priming times for each of the multiple extracorporeal blood treatments;
• the method comprising the steps of:
• defining for a specific treatment the flow rates of body fluids and medical fluids through the circuit for multiple extracorporeal blood treatments;
• in accordance with a selected one or more of the stored priming fluid instructions, priming times and priming protocols for the specific treatment, priming at least the primary circuit and at least one part of the secondary circuit by circulating a priming fluid from an end of the blood return line, through the primary chamber, and to an end of the blood access line, for the predetermined priming time for the specific treatment, and then ultrafiltering priming fluid from the primary chamber into the secondary chamber;
• in accordance with the selected one or more of the stored priming fluid instructions, priming times and priming protocols for the specific treatment, fully priming the ones of the replacement fluid line, the secondary fluid line and the collection line to be used during the defined treatment;
• in accordance with the selected one or more of the stored priming fluid instructions, priming times and priming protocols for the specific treatment, partially filling with priming fluid the ones of the replacement fluid line and the secondary fluid line not to be used during the defined treatment;
• connecting the primary circuit to a vascular system of a patient;
• circulating blood, anticoagulant fluid, replacement fluid, secondary fluid and collection fluid in the circuit for multiple blood extracorporeal treatments according to the corresponding flow rates previously defined;
• monitoring a pressure in at least one of the blood access line, the blood return line and the collection fluid line;
• monitoring a flow rate of liquid in at least one of the primary circuit, the anticoagulant fluid line, the replacement fluid line, the secondary fluid line and the collection fluid line;
• and
• stopping the circulation of at least one circulating fluid in the circuit for multiple extracorporeal blood treatments when predetermined alarm conditions occur.