Glucose Tolerance Test, 4 hour

Overview

  • EPIC Code:
  • LAB165
  • Soft Test Code:
  • GTT4
Alternate Names
  • 4 hour GTT
Included Tests

1 hour Glucose; 2 hour Glucose; 3 hour Glucose; 4 hour Glucose; Fasting Glucose


Specimen Collection & Preparation

Client Notes

Please remind patients of the time frame this testing will take, and that they need to be at the drawsite in plenty of time before closing, and will need to remain at the lab the entire time of the procedure.
These tolerance tests do not require an appointment however on the PRMC Campus, tolerance collections are performed at Parkview Outpatient Center, 11141 Parkview Plaza Drive, Suite 100 Fort Wayne, IN 46845 Entrance 3 Only.


Patient Preparation

12 hour Fasting

Smoking, drinking, gum chewing, mints, cough drops, etc… are not allowed prior to or during the duration of the test

Small amounts of water are allowed after the 1-hour specimen has been collected. 

Medications may still be taken as ordered by the physician. 


Specimen Requirements

1.0 mL Plasma in a PST Mint Green Top Tube - Li Heparin (One For Each Timed Collection)


Transport And Storage

3 days Refrigerated

4 hours Unspun


Collection Instructions

If patient has fasting test(s) ordered, they must be collected prior to administering Glucola beverage.

If possible, medications should be noted on the order

1. Collect Fasting Specimen
2. Administer the 75 grams of Glucola beverage by having the patient consume the beverage within 5 minutes
3. Start timing the test after the patient has finished the drink.
4. Collect subsequent  timed specimens will be drawn at specific time intervals, based on the test ordered

Collection hour must be included on the specimen label along with patient’s full legal name, a unique identifier (the unique identifier may be the DOB or the requisition number), date and time of collection, and the phlebotomist’s initials. 

Specimens must be spun within 4 hours of collection

For Child Glucola Dosages refer to Addendum A


Minimum Volume

0.2 mL


Neonatal Volume

Clinical Interpretation

Reference Range:

Refer to report for reference ranges


Methodology:
  • Enzymatic
Documentation

For tolerance comparisons refer to the PHL Glucose Tolerance Comparison Sheet in Addendum A


Production Schedule

Sites Performed
  • Parkview Kosciusko Hospital
  • Parkview LaGrange Hospital
  • Parkview Noble Hospital
  • Parkview Randallia Hospital
  • Parkview Regional Medical Center
  • Parkview Southwest
  • Parkview Wabash Hospital
  • Parkview Whitley Hospital
Days Performed
Monday
Tuesday
Wednesday
Thursday
Friday
Departments
  • Chemistry

Coding & Compliance

CDM

01422517, 01422518 x 2


CPT Coding

82951, 82952 x 2