Abbott i-STAT 1, Системное руководство

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20-6
Art: 714382-00D Rev. Date: 02/20/06
For example:
• uncompensated Hct = 21 %PCV
• 21 %PCV = 0.50 of 42 %
• inferred total protein = 7.0g/dL x 0.50 = 3.5 g/dL
• 21 %PCV + 3 g/dL = 24 %PCV (CPB)
Limitations of the
CPB Algorithm
The CPB algorithm is based upon a series of inferences:
• The algorithm models initial pre-pump values for total protein and
hematocrit. Although actual initial values may be different than
those used in the algorithm, typical deviations rarely affect the
accuracy of the correction by more than 0.5 %PCV. More often than
not, the actual values are consistent with a “pre-dilution” of the
modeled values.
• The algorithm assumes that the pump priming solution has no added
albumin or other colloid. The algorithm will tend to overcorrect
if solutions with added colloids are utilized, though the size of the
over-correction will seldom be more than 1 %PCV.
• Other therapies which affect the ratio of total colloids to hemaotcrit
(administration of colloids, packed red blood cells, etc.) will affect the
interference.
When to discontinue use of the CPB algorithm will depend on when the
patient's total protein level reaches the pre-pump level.
It is recommended that each practice verify the hematocrit determination for
cardiopulmonary bypass procedures so that the impact of these limitations
upon a particular practice’s protocol is understood.