Fresenius Medical Care 5008, Operating Instructions Manual

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Chapter 11: System Description
Fresenius Medical Care 5008 OP 5/09.06 11-23
Arterial path The blood passes from the patient's vascular access to the arterial
occlusion clamp. The heparin pump is located between the arterial line
clamp and the arterial pressure measurement unit, before the blood
pump. The heparin pump is used to administer heparin doses to the
blood at an adjustable rate. The arterial pressure measurement unit
measures and monitors the pressure caused by the blood pump on the
access. The pressure is transferred by a pressure dome which is
located in the tubing system and which is forced against the membrane
of the pressure measurement unit. After it has passed the arterial
pressure measurement unit, the blood reaches the blood pump. The
blood pump pumps the blood to the dialyzer.
Venous path The venous pressure port is situated next to the dialyzer. where the
venous return pressure is measured and monitored within tight limits.
The venous bubble catcher is placed into the level detector. If the level
in the venous bubble catcher falls it will be detected by the level
detector. Below the venous bubble catcher the blood passes through
the optical detector (OD). This detector differentiates between OD light
(rinse solution or air in the tubing system) or OD dark (blood in the
tubing system). The OD is followed by the air bubble detector, which
prevents infusion of air. The blood then flows from the air bubble
detector via the venous occlusion clamp back to the patient.
Single-Needle Click-Clack The blood is transported through the extracorporeal blood circuit in a
recurrent cycle. The cycle consists of the arterial and the venous
phases.
During the arterial phase, the arterial occlusion clamp is open, and the
venous occlusion clamp is closed. The blood pump is delivering. This
causes a pressure to be built up in the blood lines. When the venous
pressure has reached the upper SN pressure, the system switches to
the venous phase.
During the venous phase, the arterial occlusion clamp is closed, and the
venous occlusion clamp is open. The blood pump is not delivering. The
pressure built-up in the blood lines will be reduced. When the venous
pressure has reached the lower SN pressure, the system switches to
the arterial phase.
Blood alarms A blood alarm occurs:
– If the arterial pressure is above or below the preset limits.
– If the venous pressure is above or below the preset limits.
– If the TMP is above or below the alarm limits.
– If the air bubble detector detects air.
– If the blood pump stops for
≥
60 seconds.
– In the event of a blood leak of the dialyzer.
– Level monitored in the venous bubble catcher (warning).
– During Single-Needle Click-Clack: cycle exceeded
If a blood alarm is initiated:
– The blood pump will stop.
– The substituate pump will stop (only with ONLINE
plus ™).
– the venous occlusion clamp is closed.
– A visual and an audible alarm will be given.
– Ultrafiltration will be stopped.
– The heparin pump is stopped.