Terumo CDI 550, Operator'S Manual

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glossary appendix h H-3
Oxygen consumption ( O
2
)
A measurement of the amount of oxygen transferred to the tissues, expressed in
ml O
2
/minute.
pH
The unit for measuring the degree of acidity or alkalinity of a substance, directly
related to the concentration of hydrogen ions in the substance.
pH Stat
Maintenance of a constant pH at 7.40 and PCO
2
at 40 mmHg, over varying
temperatures; accomplished by measuring blood gas values at actual (patient)
temperature.
PO
2
Partial pressure of oxygen. The pressure exerted by oxygen gas in the blood.
PCO
2
Partial pressure of carbon dioxide. The pressure exerted by carbon dioxide gas in
the blood.
Parameter display window
The window on the CDI System 550 Monitor’s screen that contains case param-
eter data.
Potassium (K
+
)
The major cation of intercellular fluid.
Blood flow value, in L/min obtained manually or via the pump interface port.
Soft keys
Software-driven function keys located along the right side of the monitor’s front
panel.
Standard deviation (precision)
A measure of how spread out the values in a data set are. This measure tells
whether most of the values in a data set are close to the average or widely
distributed around the average. This is the most common measure of variability.
Variance is the average squared deviation from the mean. Standard deviation is
the square root of the variance. In a normal distribution of values — that is, a set
of values that are distributed evenly around the mean of the data set — 68% of
the values are b/− 1 standard deviation, and about 95% of the values
are b/− 2 standard deviations. The goal of quality control when studying
precision is to keep standard deviations as small as possible.