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Universal Servo Controlled Perfusion System

  • Perfusion possible with very small perfusate quantity
  • Accurate control of perfusion pressure or flow
  • Compact arrangement of perfusion circuit
  • Flexible perfusion circuit setup adjusts to suit individual perfusion conditions

The Universal Servo Controlled Perfusion System is used for the perfusion of organs and tissues using a peristaltic pump. It is a conventional PID controller which operates to maintain either a constant perfusion pressure or a constant perfusion flow.

The following additional items are required to complete the system:

Function

The pressure or flow measuring system evaluates the perfusion pressure or perfusion flow (= actual value X). This value is fed in to the "actual value" analog input of the SCP PLUGSYS module (over the PLUGSYS bus). The SCP has a provision for setting the required perfusion pressure (e.g. 100 mmHg) or perfusion flow (e.g. 50 ml/min) which represents the setpoint X. From the actual value and the setpoint value, the SCP module produces a control voltage (Y) for the pump (roller pump, centrifugal pump ...) so that the required perfusion pressure or perfusion flow is produced.

Control system for constant-pressure perfusion

A diagram of a control system for constant-pressure control is shown, using kidney perfusion as an example. The required perfusion pressure (= set pressure = SETPOINT X) is set on the SCP. This output signal controls the flow rate of the pump.

Operation: The pressure transducer (3) measures the perfusion pressure close to the organ and passes this to the bridge amplifier TAM-A (4). The output signal of the TAM-A corresponds to the perfusion pressure present at the organ (= actual pressure = X). This pressure signal is passed through the PLUGSYS® system bus to the IN X input of the SCP (5). The SCP compares this ACTUAL signal with the SET VALUE (= SETPOINT X) and produces a control signal (Y) which operates the pump in such a way that the perfusion pressure agrees as closely as possible with the set value.
 

Control system for constant-flow perfusion

The diagram shows a control system for constant-flow, using liver perfusion as an example. The required perfusion flow (= flow setting = SETPOINT X) is set on the SCP whose output signal controls the flow rate of the pump.

Operation: The flow transducer (3) measures the perfusion flow and passes this to the flowmeter TTFM (4). The output signal of the TTFM corresponds to the actual perfusion flow at the organ (= actual flow = X). This flow signal is passed through the PLUGSYS® system bus to the IN X input of the SCP (5). The SCP compares the actual signal with the SET VALUE (= SETPOINT X) and produces a control signal for the pump (6) so that the flow rate corresponds as closely as possible to the set value.


Checklist for more information
or quotation on
Isolated Organ Perfusion Systems


HUGO SACHS ELEKTRONIK-HARVARD APPARATUS GmbH
Gruenstrasse 1 · D-79232 March-Hugstetten · GERMANY
Phone: +49 (0) 76 65 - 92 00-0 · Fax: +49 (0) 76 65 - 92 00-90