Specimen Requirements

Collection Instructions:

1. Serum and Plasma gel tubes should be centrifuged within 2 hours of collection.

2. Red-top tubes should be centrifuged and aliquoted within 2 hours of collection.

Submit only 1 of the following specimens:

Preferred:

Serum

Draw blood in a gold-top serum gel tube(s). Spin down and send 1 mL of serum refrigerated. For theophylline SR tabs, trough specimen is usually drawn just prior to next oral dose; and peak specimen is usually drawn 4 hours after dose. For theophylline continuous infusion, trough specimen is usually drawn 24 hours after start of maintenance infusion; and peak specimen is usually drawn at 1/2 hour and 8 hours after loading dose and start of continuous infusion.

Note:  1. Date and time of draw is required on request form and specimen for processing.

2. A speckled-top serum gel tube (s) or a plain, red-top tube(s) is also acceptable.

3. Indicate serum on request form.

4. Label specimen appropriately (serum).

Alternate: Preferred for VWH Lab

Plasma

Draw blood in a mint green-top (heparin) gel tube(s). Spin down and send 1 mL of heparinized plasma refrigerated. For theophylline SR tabs, trough specimen is usually drawn just prior to next oral dose; and peak specimen is usually drawn 4 hours after dose. For theophylline continuous infusion, trough specimen is usually drawn 24 hours after start of maintenance infusion; and peak specimen is usually drawn at 1/2 hour and 8 hours after loading dose and start of continuous infusion.

Note: 

1. Date and time of draw is required on request form and specimen for processing.

2. Indicate plasma on request form.

3. Label specimen appropriately (plasma).

VWH Lab: 

4. Tubes of blood are to be kept closed at all times and in a vertical position. It is recommended that the serum or plasma be physically separated from contact with cells within two hours from the time of collection.

5. Separated serum or plasma should not remain at room temperature longer than 8 hours. If assays are not completed within 8 hours, serum or plasma should be stored at +2°C to +8°C for up to 48 hrs. 

Roche Specimen Stability Information