PLUGSYS Modules

Control modules

PPCM

Perfusion Pressure Control Module type

The Perfusion Pressure Control Module PPCM has been especially designed for use in experiments on the LANGENDORFF Isolated Heart or the Working Heart. It is used to maintain a constant perfusion pressure and provides flexible pressure adjustment. Through its facility for very rapid changes in perfusion pressure this set-up is particularly suitable for testing the autoregulatory function of the heart (BAYLISS effect). A staircase function is provided and very high pressures can be reached so that load tests can be extended up to ventricular failure. The unit consists of the PPCM module which is plugged into the basic system case. Connected to it are the control box and the flush box with valve and roller pump. It is possible to set the control functions manually (set pressure, set pressure steps, make pressure steps up and down) or to control all these functions by a computer (ISOHEART Software).

Description

PPCM MODULE TYPE 671

TO CONTROL BOX the control unit which carries all control elements and which can be placed near the apparatus is connected to this socket

TO PUMP in order to ensure optimum oxygen saturation a small continuous gas flow is required. This is achieved through a roller pump (Flush Box). Rapid reductions in perfusion pressure are obtained by discharging through a solenoid valve. Roller pump and valve are contained in the flush box and must be placed near the apparatus. The connection to the PPCM module is made with a 9-pin connector.

GAS INLET connection to the primary pressure of the gas supply through a pressure
reducer, max. input pressure to this inlet 500 mbar.

OUTLET output for the controlled pressure which must be connected to the LANGENDORFF or Working Heart apparatus (oxygenator).

G this trimmer potentiometer is used to adjust the GAIN of the control system for perfusion gas pressure.

Z this trimmer potentiometer is used to adjust the Zero (Offset) of the measuring system for perfusion gas pressure

CONTROL BOX FOR PPCM

GAS SELECT 4 different gas mixtures can be selected with this switch in conjunction with the Gas
Select module (GSM). The system is first vented and then charged with the new gas mixture.

MEASURED PERFUSION
PRESSURE this display shows the measured perfusion pressure in mmHg.

RELEASE PRESSURE pressing this key vents the system to atmospheric pressure. Used as emergency
switch-off if the perfusion flow is too high. This prevents gas embolism.

ERROR this display shows the following errors: "P" input pressure is missing, "H" gas flow to
the oxygenator is too high, "L" gas flow to the oxygenator is too low.

DISPLAY PRESET the pressure step is set by pressing this key and turning the rotary switch. The ampli-
tude of the step in mmHg is shown on the PRESET PRESSURE display.

STEP UP increases the pressure in the oxygenator depending on the step amplitude

STEP DOWN decreases the pressure in the oxygenator depending on the step amplitude

PRESET PRESSURE this display shows the preset perfusion pressure. By pressing the SET key this pres-
sure is set in the oxygenator

SET LOCK if this key is pressed then the chosen preset pressure is directly set on the oxy-
genator without pressing the SET key.

SET sets the pressure in the oxygenator to the chosen value (PRESET PRESSURE).
At the beginning of the experiment the hydrostatic pressure should be subtracted
from the perfusion pressure. This can be done, after switching on the system, by set- ting the hydrostatic pressure in the preset pressure display and pressing the SET
key.

REMOTE this LED is on when the computer is controlling the PPCM. In this case all keys on
the CONTROL BOX are out of action except for the RELEASE PRESSURE key
which functions as emergency cut-out to set the system to atmospheric pressure in
case of a mistake.

POWER the power for the electronics as well as the solenoid valves and pumps is supplied through the PLUGSYS bus system.
+ 5 V/800 mA, + 24 V/0.9 mA

Dimensions
Module for 19inch rack, width 8E (40.5 mm), height 3U (128.7 mm), depth Europe size (220 mm)

Control Box bench housing, H = 100 mm, W = 220 mm, D = 160 mm, cable 2 m long

FLUSH BOX small housing, H = 240 mm, W = 100 mm, D = 100 mm, cable 2 m long

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

TO CONTROL BOX	the control unit which carries all control elements and which can be placed near the apparatus is connected to this socket
TO PUMP	in order to ensure optimum oxygen saturation a small continuous gas flow is required. This is achieved through a roller pump (Flush Box). Rapid reductions in perfusion pressure are obtained by discharging through a solenoid valve. Roller pump and valve are contained in the flush box and must be placed near the apparatus. The connection to the PPCM module is made with a 9-pin connector.
GAS INLET	connection to the primary pressure of the gas supply through a pressure reducer, max. input pressure to this inlet 500 mbar.
OUTLET	output for the controlled pressure which must be connected to the LANGENDORFF or Working Heart apparatus (oxygenator).
G	this trimmer potentiometer is used to adjust the GAIN of the control system for perfusion gas pressure.
Z	this trimmer potentiometer is used to adjust the Zero (Offset) of the measuring system for perfusion gas pressure

GAS SELECT	4 different gas mixtures can be selected with this switch in conjunction with the Gas Select module (GSM). The system is first vented and then charged with the new gas mixture.
MEASURED PERFUSION PRESSURE	this display shows the measured perfusion pressure in mmHg.
RELEASE PRESSURE	pressing this key vents the system to atmospheric pressure. Used as emergency switch-off if the perfusion flow is too high. This prevents gas embolism.
ERROR	this display shows the following errors: "P" input pressure is missing, "H" gas flow to the oxygenator is too high, "L" gas flow to the oxygenator is too low.
DISPLAY PRESET	the pressure step is set by pressing this key and turning the rotary switch. The ampli- tude of the step in mmHg is shown on the PRESET PRESSURE display.
STEP UP	increases the pressure in the oxygenator depending on the step amplitude
STEP DOWN	decreases the pressure in the oxygenator depending on the step amplitude
PRESET PRESSURE	this display shows the preset perfusion pressure. By pressing the SET key this pres- sure is set in the oxygenator
SET LOCK	if this key is pressed then the chosen preset pressure is directly set on the oxy- genator without pressing the SET key.
SET	sets the pressure in the oxygenator to the chosen value (PRESET PRESSURE). At the beginning of the experiment the hydrostatic pressure should be subtracted from the perfusion pressure. This can be done, after switching on the system, by set- ting the hydrostatic pressure in the preset pressure display and pressing the SET key.
REMOTE	this LED is on when the computer is controlling the PPCM. In this case all keys on the CONTROL BOX are out of action except for the RELEASE PRESSURE key which functions as emergency cut-out to set the system to atmospheric pressure in case of a mistake.