Glucose Tolerance, Gestational Screen 1 Hour (50g)

Abbrev Code:GLU1   
Order Code:LAB3503Order Name:Glucose Tolerance, Gest Screen1 Hour
Synonyms:GTT; Glucose Challenge
Methodology:Bichromatic endpoint, glucose oxidase
Woodwinds: Hexokinase
CPT Codes: 82950 x1, 82952 x1
Test Includes:Blood glucose level collected one hour after ingestion of 50 g glucose
Turnaround Time:Performed Mon-Fri, 0700-1700; turnaround time is 2 hours routine, 40 minutes stat.
Special Instructions:This is a screening test usually administered between 24-28 weeks of pregnancy.
Associated Links:

Roche Go Live Schedule

Collection Instructions

Optimal Volume:2.5 mL
Minimum\Peds Volume:0.6 mL
Collection Instructions:Chemistry Tests Containers Chart
Glucose Tolerance Protocol  
Outpatient Laboratory will collect specimens in green top (heparin) or red/black top (gel) tubes to avoid hemolysis.
For Womens Health Clinic:
  1. WHC will drop off request form to be filed in the future order file.
  2. Patient will check into the lab to drink the 50 g glucola (no blood is drawn pre-glucola for the 50 g screen).
  3. OP Lab will set the timer for 1 hour.
  4. OP Lab will send a lab staff to WHC to draw the 1 hour post sample and other labs if needed.
Patient Preparation:Patient does not need to be fasting and needs no preparation. The gestational diabetic screen is performed without regard to last meal or time of day.
Contraindications:If patient becomes ill or vomits, test must be discontinued.

Processing and Shipping

Specimen Processing:Centrifuge and aliquot 1.25 mL, 0.2 mL minimum. Store in refrigerator.
Shipping Instructions:Ship at refrigerated temperature.
Stability:Roche and Vista: Once separated from cells: 8 hours at room temperature; 72 hours refrigerated.
Test Performed at or Referral Lab Chemistry  (Clinics, CSC Maple Grove, Roche-CSC Mpls, Roche-Grand Itasca, Roche-Lakes, Roche-Northland, Roche-Range, Roche-Ridges, Roche-Southdale, Roche-St. John's, Roche-UMMC East, UMMC/UMMCH-West Bank, Woodwinds)


Critical Range:Glucose Tolerance Reference Ranges
Reference Range:Glucose Tolerance Reference Ranges

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