Fresenius Medical Care 2008K Operator's Manual page 84

Chapter 4—Monitoring the Treatment
Bar graphs on the Home Screen
The three bar graphs on the "Home" screen represent the various pressures associated with
dialysis treatment. The first two bar graphs represent the pressures inside the arterial and venous
drip chambers. The third bar graph—Transmembrane Pressure (TMP)—represents the opposing
blood and dialysate pressures being exerted from opposite sides on the dialyzer membrane.
Warning! The pressure changes resulting from a line separation or needle removal may be too
small for the system to detect. All connections must be properly secured and checked
regularly. Access sites and connections should remain uncovered for monitoring.
Arterial Pressure
The arterial pressure is the measure of the pressure inside the arterial drip chamber. The arterial
pressure is read by a transducer inside the blood pump module. The drip chamber and transducer
are connected by way of a pressure line that runs from the arterial drip chamber to the blood
pump's arterial pressure port (P
guard against contamination of the transducer in case of a fluid surge within the chamber.
magnitude the pressure deviates outside the alarm window, allows for momentary minor changes
in pressure. Adjusting the blood pump rate will cause the alarm limits to spread, allowing the
pressure to stabilize before new limits are re-established
Venous Pressure
The venous pressure is the measure of pressure inside the venous drip chamber. The venous
pressure is measured by a pressure transducer located inside the level detector module. The drip
chamber and transducer are connected via a pressure line that runs from the chamber to venous
pressure port (P
84
). A transducer protector is fastened over the pressure port to
Art.
Arterial pressure is digitally displayed on the left side of the "Home" screen above
a corresponding vertical bar graph. In the bar graph, under normal conditions,
arterial pressure is represented by a green horizontal bar between two yellow bars
that represent the upper and lower alarm limits. The area between the limits is the
alarm window. The alarm limits are automatically set. When the arterial drip
chamber is positioned before the blood pump in the extracorporeal blood circuit,
the arterial pressure reading should be a negative value.
Unusually high or low pressures may be the result of kinks in the blood tubing,
clotting, or a needle pressing against the vessel wall. Problems such as these may
cause pressure readings to rise or fall outside the alarm window. When this
happens, the arterial pressure bar changes from green to red, an alarm sounds, the
blood pump stops, and venous line clamp closes. A warning message appears in
the Status box.
Alarms are not immediate and a variable time delay mechanism, dependant on the
) located on the front of the module.
Ven.
2008K Operator's Manual rev. K