Pseudocholinesterase, Dibucaine Inhibition
Ordering Recommendation
Order to detect increased sensitivity in individuals who experience prolonged paralysis following succinylcholine or mivacurium administration.
New York DOH Approval Status
Specimen Required
Specimen must be drawn prior to surgery or more than two days following surgery. Do not draw in recovery room.
Serum separator tube, plain red, 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)
Refrigerated
Lt. blue (sodium citrate) or gray (oxalate/fluoride). Whole blood.
Room Temperature: 4 hours; Refrigerated: 1 week; Frozen: 3 months
Methodology
Quantitative Enzymatic Assay
Performed
Mon-Fri
Reported
1-5 days
Reference Interval
| Test Number |
Components |
Reference Interval |
|---|---|---|
| Pseudocholinesterase, Total | 2,900-7,100 U/L | |
| Dibucaine Number | Greater than or equal to 80 |
Interpretive Data
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.
Laboratory Developed Test (LDT)
Note
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.
Hotline History
Hotline History
CPT Codes
82638; 82480
Components
| Component Test Code* | Component Chart Name | LOINC |
|---|---|---|
| 0020059 | Pseudocholinesterase, Total | 2098-2 |
| 0020060 | Dibucaine Number | 39354-6 |
Aliases
- Butyrylcholinesterase
- Cholinesterase
- Cholinesterase, Serum
- Dibucaine
- Dibucaine Inhibition
- Dibucaine Number
- Serum Cholinesterase
- Serum Pseudocholinesterase
















