Fresenius Medical Care 2008K Operator's Manual page 98

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
pressure port to guard against contamination of the transducer in case of a fluid surge within
the chamber.
appears in the Status Box.
Alarms are not immediate and a variable time delay mechanism, dependant on the 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
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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
). A transducer protector is fastened over the
Art.
2008K Hemodialysis Machine Operator's Manual Rev P