Order to detect increased sensitivity in individuals who experience prolonged paralysis following succinylcholine or mivacurium administration.
Quantitative Enzymatic Assay
New York DOH Approval Status
Specimen must be drawn prior to surgery or more than two days following surgery. Do not draw in recovery room.
Serum separator tube, green (sodium or lithium heparin), lavender (EDTA), or pink (K2EDTA).
Allow specimen to clot completely at room temperature. Separate serum or plasma from cells ASAP or within 2 hours of collection. Transport 1 mL serum or plasma. (Min: 0.25 mL)
Lt. blue (sodium citrate) or gray (oxalate/fluoride). Whole blood.
Ambient: 4 hours; Refrigerated: 1 week; Frozen: 3 months
|Pseudocholinesterase, Total||2,900-7,100 U/L|
|Dibucaine Number||Greater than or equal to 80|
The dibucaine number (DN) is the percent of pseudocholinesterase (PChE) enzyme activity that is inhibited by dibucaine. Together, the DN and the PChE enzyme activity results can help to identify individuals at risk for prolonged paralysis following the administration of succinylcholine. Decreased PChE enzyme activity in conjunction with a DN less than 30 suggests high risk for prolonged paralysis. Normal to decreased PChE enzyme activity in conjunction with a DN 30-79 suggests variable risk. Although decreased PChE activity in conjunction with DN greater than or equal to 80 suggests variable risk, these results may be caused by exposure to organophosphates, the presence of liver disease, pregnancy, or circulating succinylcholine. Specimens should be collected 48 hours after the administration of succinylcholine.
This test was developed and its performance characteristics determined by ARUP Laboratories. It has not been cleared or approved by the US Food and Drug Administration. This test was performed in a CLIA certified laboratory and is intended for clinical purposes.
Laboratory Developed Test (LDT)
Patients with acute or chronic liver disease, organophosphate poisoning, chronic renal disease, in late stages of pregnancy, or on estrogen therapy may have markedly decreased PChE activities.
|Component Test Code*||Component Chart Name||LOINC|
- Cholinesterase, Serum
- Dibucaine Inhibition
- Dibucaine Number
- Serum Cholinesterase
- Serum Pseudocholinesterase