Phenytoin, total & free-90

Test info

  
Phenytoin, total & free
  
90
  
LAB90
  
PTF
  
Cerebyx
Dilantin
DPH
Fosphenytoin
PHT
  

Fosphenytoin is ProDrug of Phenytoin and is measured as Phenytoin

Specimen

  
Lithium heparin (Li hep) plasma
  
  
2.0 mL
  
0.2 mL
  
  • Specimen should be collected:
    • Peak (regular release): 1-3 hours post dose
    • Peak (slow release): 4-12 hours post dose
    • Trough: Immediately prior to next dose
  • Immediately following collection, mix sample thoroughly by gently inverting 8 - 10 times to prevent clotting
  

Spin within two (2) hours of sample collection

  

Lt green plasma separator (PST)

  
Serum
  
  

Immediately following collection, thoroughly mix sample by gently inverting 5 times

  
  1. Allow sample to clot for a minimum of 30 minutes
  2. Spin within two (2) hours of sample collection
  

Gold serum separator (SST) tube

  

Refrigerated (preferred) - 7 days

Ambient - 2 days

Frozen - 5 months

  
  • Improper labels (unlabeled or mislabeled)
  • Hemolysis (some procedures)
  • Improper anticoagulant or ratio
  • Delay in transport
  • Improper storage temperature affecting results
  • Inappropriate timing of collection
  • Improper container
  • Leaking container resulting in compromised specimen
  • Quantity not sufficient (QNS)

Performance

  
AHL - Chemistry: C
  
Daily
  
1 day
  

Chemiluminescent Micro-particle Immunoassay (CMIA)

Clinical and Interpretive info

  

Total: 10.0 - 20.0 µg/ mL

Free:    1.2 - 2.5 µg/mL

  

Total: >30.0 µg/mL

Free:  > 3.0 µg/mL

Billing

  
80185
80186

Tracking

  
11/30/2001
  
02/12/2020
  
02/10/2020