Gambro AK 95 S, Service Manual

Page: 23 / 247

Technical Description
AK 95 / AK 95 S Service Manual
HCEN 9134 Rev. 10.2005
2:2
General
The AK 95 S is designed to be used as a single
patient machine to perform conventional hemo-
dialysis. The AK 95 S can be divided into three
parts:
• Blood part
• Fluid part
• Operators panel
The blood part is used to control and monitor
the extra corporeal blood flow through the
dialyzer and, where applicable, to control the
addition of heparin to the blood before dialysis.
Both Single needle and Double needle treatment
are carried out with one blood pump.
Disposable blood lines are used for the blood
flow. The blood part includes the following main
functions:
• Blood flow regulation
• Venous blood pressure monitoring
• Arterial pressure monitoring
• Heparin flow regulation
• Air detection
• Priming detector
• Arterial and venous line clamps control
The fluid part is used to produce dialysis fluid
(with the correct temperature and correct
conductivity) from water and concentrate, and to
transport the fluid through the dialyzer.
The fluid part maintains the dialysis flow
through the dialyzer with controlled ultrafilt-
ration.
If a fault occurs, the fluid part bypasses the
dialyzer.
AK 95 S fluid part includes the following main
functions:
• Inlet pressure monitoring.
• Temperature monitoring and regulation.
• Conductivity monitoring and regulation.
• Degassing pressure and flow regulation.
• UF measuring and regulation.
• High pressure monitoring.
• TMP monitoring.
• Blood leak detection.
• pH meassurement of the fluid, optional.
Introduction
AK 95 S operates in either acetate- or
bicarbonate mode. In bicarbonate mode the
monitor mixes dialysis fluid from water and two
concentrates: acid and bicarbonate. The mode is
selected from the operator's panel.
A disinfection must be performed after every
treatment. Both heat disinfection and chemical
disinfection are available.
The power supply supplies the AK 95 S with the
necessary supply voltages. The mains voltage is
also used to supply the heater within the AK 95
S.
The AK 95 S is operated from the operators
panel located on the blood part. The panel has
an overlay translated into different languages.
For information about the use and function of
the panel, see the document
AK 95 Operators
Manual, HCEN 9542 or AK 95 S Operators
Manual, HCEN 9794 .
Protective system
AK 95 S is equiped with a protective system.
The main task is to supervise the dialyzing
process and if needed take correct action to
prevent hazard to the patient. The protective
system can take actions independently of the
control system. It is a separate system, with its
own sensors and electronics.
Protective system is responsible for setting the
AK 95 S in a patient safe state when any of the
supervised parameters exceed their approved
limits.
The control system has to start up the AK 95 S
in a controlled way when the hazardous situa-
tion is cleared.
The kind of action that is to be taken depends of
in which state the AK 95 S is, for example
treatment or disinfection.
Another task of protective system is to make a
function check of AK 95 S sub systems.
The protective system of AK 95 S is separated in
two parts, the blood part and the fluid part.