W. S. TOPHAM 
1223 
Figure 4. — The remote terminal (Beehive Medical Electronics a-21) used in the computer system. A storage tube 
display gives 512 by 412 point graphic capability. 
tification message. The correct patient and de- 
vice number are entered and verified, as is the 
number of the analog channel transmitting 
data. To continue, button '3' is pushed. This 
stores the entered values on the disk, and the 
main message is displayed on the oscilloscope. 
If this is the first time the dye curve is run, 
then calibrations are taken. Black and saline 
values give the range of the cuvette. Black is 
the voltage from the cuvette with no light being 
detected and is obtained by an electrical setting. 
The saline value is obtained by withdrawing sa- 
line through the cuvette and sampling the out- 
put voltage. Blood is then drawn through the 
cuvette and zero dye calibration is taken. Dye is 
added to the sample to provide a concentration 
of 12.5 mg/1 and reinfused through the cuvette 
while the 12.5 mg calibration value is sampled. 
If these values are satisfactory, then '4' is 
pushed and the calibration values are stored on 
the disk so they can be recalled and used for fu- 
ture dye curve analysis. 
It is then necessary to enter the number of 
seconds the dye curve is to be sampled. This is 
usually about forty seconds. Whenever a value 
is to be entered, a double asterisk will appear by 
the number which has been pressed and will re- 
main until the value is entered and the 'SEND' 
button pushed to enter that value into the pro- 
gram. The amount of dye to be injected is en- 
tered depending on the size of the animal. This 
is usually two ccs of dye when a concentration 
of 12.5 mg/1 is used. If all the values are cor- 
rect and verified, then arterial blood is with- 
drawn through the cuvette oximeter, and at the 
moment the dye is injected into the venous sys- 
tem, the number 'T is pressed. The program 
then samples the output of the cuvette for a pe- 
riod of time specified as the dye circulates 
through the animal and the cuvette. 
