User's Manual

Ultraview Care Network
19-6
Entering the Computational Constant
To generate calculations, you must first enter the computational constant (CC)
and verify that the system is correctly configured. Refer to your thermodilution
catheter package insert for current constants.
The temperature of the injectate changes due to contact with the catheter wall and
the surrounding blood. To account for this interaction, the system includes a
correction factor in the equation. The correction factor (K or CT) is a function of
catheter and flow-through housing dimension, internal volume, and injectate
temperature and differs among catheter models and manufacturers.
Once you enter a value for the computational constant, the value is displayed on
the CC= key and remains in system memory. Until you enter the computational
constant, the message CC REQUIRED is displayed, and ENTER
COMPUTATIONAL CONSTANT is displayed on the message line after the CC=
key is selected.
Entering Patient Height/Weight
To perform indexed hemodynamic calculations, you must enter the patient’s
height and weight before you generate CO curves. CO uses the patient’s height
and weight entered during the admit function.
The valid range for height is 10 to 85 in (25 to 215 cm). The valid range for weight
is 2 to 400 pounds (1 to 180 kg). After you enter both height and weight values,
the system automatically calculates and displays the patient’s body surface area
(BSA).
Measuring Cardiac Output
To maintain the accuracy of the readings, you must allow the catheter to warm up
between injections. When in AUTO mode, wait until the INJECT WHEN READY
message appears between injections. When in MANUAL mode, wait until the
TOUCH START THEN INJECT message appears.
Five curves can be displayed at one time. Some curves may automatically be
classified as “bad,” in which case they are then labeled BAD CURVE and are
automatically excluded from averaging. CO curves are numbered consecutively
from 1 to 99.
A 15-minute timer begins after acquisition of the first good curve. After
15-minutes, the AUTO/MANUAL and START keys become invalid (dotted), and
the messages MUST SELECT CURVES, AVERAGE, STORE, or CLEAR CO
appear. Cardiac output injections are disabled until you perform one of these
actions. Injections may resume as soon as the INJECT WHEN READY or TOUCH
START, THEN INJECT message appears.
!
• To obtain all hemodynamic calculations remember to enter
height and weight, and to store a PCWP prior to initiating
measurement of CO.
To enter the computational
constant:
1 Touch CO.
2 Touch CC =.
3 Touch the appropriate keys
(tenths, hundredths, and then
thousandths) and use arrow
keys to adjust.
4 Touch ENTER.
To enter patient height and
weight:
1 Touch CO.
2 Touch HEIGHT/WEIGHT.
3 Select HEIGHT = and/or
WEIGHT =.
4 Use arrow keys to adjust.
5 Touch ENTER.
To obtain CO measurements:
1 Touch CO.
2 Touch CARDIAC OUTPUT.
3 Select AUTO or MANUAL.
4a Wait for the INJECT WHEN
READY or the TOUCH START
THEN INJECT message to
display.
-OR-
4b If in manual mode, touch
START.
5 Inject the prepared injectate
into the proximal lumen of the
thermodilution catheter.