Test Code GTTPRENAT75G Glucose Tolerance, Prenatal, 75G, Serum or Plasma
Additional Codes
- Expanse Test Name:Glucose Tolerance: Prenat 75G
- Medinet Ref Code:GTT75
- OV Code:CHEM*GTTPRENAT75G
Performing Laboratory
St. Lukes Hospital Laboratory
Methodology
Enzymatic/Hexokinase
Specimen Requirements
Patient Preparation:Patient should be fasting (8-14 hour).
Performance of Test:
1. Draw blood for a fasting glucose level.
2. Obtain 75 g of glucose solution.
3. If patient is <100 pounds, a smaller dose of glucose solution should be calculated by the laboratory.
4. Have patient consume glucose solution within 5 minutes.
5. Start timing from first sip.
6. Draw specimen at 1-,and 2-hours post glucose solution ingestion.
Note: If patient cannot completely consume glucose solution (or cannot keep it down) or drinks part of the glucose solution and spills the rest, the test must be cancelled and rescheduled.
Specimen Collection:
Submit only 1 of the following specimens:
Plasma
Draw blood in a green-top (lithium heparin) plasma gel tube(s).
Spin down and send 1 mL of lithium heparin plasma refrigerated.
Note: 1. Indicate time of draw and
plasma on request form.
2. Label specimen appropriately (time of draw and plasma).
Serum
Draw blood in a serum gel tube(s). Spin down and send 1 mL of serum
refrigerated.
Note: 1. Indicate time of draw and
serum on request form.
2. Label specimen appropriately (time of draw and serum).
Unspun specimens must be transported at ambient temperature and arrive to the laboratory within one hour of draw.
Reference Values
Diagnostic criteria for the 75 g oral glucose tolerance are as follows:
≥92 mg/dL fasting
≥180 mg/dL at 1 hour
≥153 mg/dL at 2 hours
Any single value greater that these criteria is diagnostic of Gestational Diabetes.
Day(s) Test Set Up
Monday through Friday
Test Classification and CPT Coding
CPT: 82951 - 3 specimens