Caffeine

Test Code

CAFF

CPT Codes
83520

Preferred Specimen

Serum (gold or red top tube)

Minimum Volume

0.5 mL

Transport Container

Serum (gold or red top) Tube

Transport Temperature

Room Temperature or Refrigeration

Specimen Stability

Room Temperature - 1 week; Refrigerated - 1 week

Reject Criteria (Eg, hemolysis? Lipemia? Thaw/Other?)

Quantity Not Sufficient, EDTA (purple top tube) contamination, IV contamination

Methodology
Turbidimetric

Setup Schedule

Daily upon receipt

Report Available

Upon completion of analysis

Reference Range

5.0 - 15.0 ug/mL

Clinical Significance

Caffeine is a mild stimulant and a minor metabolite of theophylline. Both are classified as methylxanthines. Methylxanthines are used to control and prevent neonatal apnea. Premature infants receiving theophylline have significant levels of caffeine in their blood because they metabolize theophylline to caffeine. Because the theophylline concentration is a poor indicator of the serum caffeine level, both caffeine and theophylline should be measured in premature infants receiving theophylline. By doing so, the total methylxanthine level can be assessed, thus avoiding toxicity. In premature infants receiving theophylline, caffeine has a long half-life and is therefore easily accumulated. The caffeine half-life in infants varies from 30 to 200 hours. As the metabolism of premature infants matures during the first 3 to 6 months of life, their caffeine half-life reaches adult rates of 4 to 6 hours. The wide range seen in premature infants is due to individual variations in caffeine metabolism.

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.