Cholinesterase, Plasma

Casandra

Casandra Test Code LC02763Version 1 (DRAFT)

Performing Lab

Lab LabcorpLab Test ID 160200CPT Code 82480

Cholinesterase, Plasma

Also known as: Benzoylcholinesterase, Choline Esterase II, Pseudocholinesterase, Plasma

Clinical Use

Order Test

Use

Evaluate preoperative patients for succinylcholine (suxamethonium) anesthetic sensitivity, genetic or secondary to insecticide exposure, in appropriate circumstances. To prevent or evaluate prolonged anesthetic effect, prolonged apnea, after surgery. Very small amounts (0.04−0.06 mg/kg) of succinylcholine are needed to obtain 90% of neuromuscular blockade in patients with low levels of plasma cholinesterase activity.1

Special Instructions

The value of assessing risk status using plasma or serum cholinesterase levels for organophosphate exposure has been questioned. Interpretative problems may arise with low or high values. Very small amounts of succinylcholine are needed to obtain 90% neuromuscular blockade in patients with low plasma cholinesterase activity.

Limitations

Plasma cholinesterase may be decreased in individuals on estrogens or oral contraceptives, and fluoride interferes with the test. Pseudocholinesterase may be low in cases of liver disease and other conditions, but not consistently enough to be a useful clinical test for such disorders. The discovery of genetic atypical enzymes does not explain all cases of prolonged postsurgical apnea. Whole blood specimens can alter levels if plasma remains in contact with red cells for extended periods.

Test Details