Extracorporeal blood handling system with automatic flow control and methods of use

Abstract

Apparatus for processing blood in an extracorporeal circuit with automatic flow control is provided in which error conditions are sensed and system operation is modulated responsive to the error conditions. The apparatus includes an extracorporeal blood processing system, at least one sensor that senses the presence or absence of gas or monitors venous pressure, and a controller operably coupled to the blood processing system to selectively reduce pump speed or to reconfigure flow paths within the blood processing system responsive to the sensor output.

1 - 28 . (canceled)  
     
     
         29 . A method of handling trigger conditions in an extracorporeal circuit for processing blood, comprising: 
 providing a blood processing system having a pump, a filter, an oxygenator, a sensor and a controller, the blood processing system having an inlet to receive blood from a patient via a venous line and an outlet for reperfusing blood to the patient via an arterial line;    detecting the presence of air in the venous line or the blood processing system with the sensor and generating an output; and    evaluating the output of the sensor using the controller; and    modulating operation of the blood processing system responsive to the output while retaining some forward flow through the arterial line to the patient.    
     
     
         30 . The method of  claim 29 , wherein modulating the operation of the blood processing system comprises reducing a speed of the pump responsive to the output.  
     
     
         31 . The method of  claim 30 , wherein the blood processing system further comprises a valve coupled to a vacuum source, the valve is configured to be selectively actuated by the controller responsive to the output of the sensor, and modulating the operation of the blood processing system further comprises monitoring actuation of the valve.  
     
     
         32 . The method of  claim 31 , wherein monitoring actuation of the valve comprises monitoring duration of actuation of the valve.  
     
     
         33 . The method  claim 29 , wherein the sensor is disposed on the venous line, the method further comprising monitoring pressure in the venous line.  
     
     
         34 . The method of  claim 30 , wherein reducing the speed of the pump comprises reducing the speed of the pump to a predetermined limit to a predetermined limit value or predetermined percentage.  
     
     
         35 . The method of  claim 34 , wherein reducing the speed of the pump comprises reducing the speed of the pump in predetermined increments.  
     
     
         36 . The method of  claim 29 , wherein the blood processing system further comprises a valve operably coupled to the arterial line, and modulating operation of the blood processing system comprises changing a configuration of the valve.  
     
     
         37 . The method of  claim 36 , wherein modulating operation of the blood processing system further comprises reducing a speed of the pump.  
     
     
         38 . The method of  claim 37 , wherein the blood processing system further comprises a recirculation line disposed between the inlet and the outlet and a valve operable coupled to the recirculation line, and modulating operation of the blood processing system further comprises changing a configuration of the valve.  
     
     
         39 . The method of  claim 29 , wherein the blood processing system further comprises a recirculation line disposed between the inlet and the outlet and a valve operable coupled to the recirculation line, and modulating operation of the blood processing system comprises changing a configuration of the valve.  
     
     
         40 . The method of  claim 38 , wherein modulating operation of the blood processing system further comprises reducing a speed of the pump.