Test Volume Requirements
The only acceptable sample for a complete blood count (CBC) and reticulocyte count is EDTA whole blood (lavender top tube). The minimum sample size is 150 uL plus two slides made at the site. Do not freeze the whole blood.
Sodium citrate tubes (blue top): Citrate tubes should be filled to the top. For small volumes, sample may be collected in a tube with a ratio of one part sodium citrate and nine parts blood. Gently mix specimen by inverting at least 5-6 times and place immediately at 4°C for up to 30 minutes before being spun in a centrifuge. The following tests can be performed on 500 uL of frozen plasma. Minimum sample size for Individual test is 250 uL.
- Prothrombin Time (PT)
- Activated Prothrombin Time (APTT)
Sample: Serum or plasma samples (serum is preferred) collected in red top or SST, red/camouflage top tubes. Both plain and SST tubes must be allowed to clot at 4°C for 30 - 60 minutes. Then the samples must be centrifuged at 7000 rpm for 10 minutes and the serum decanted and frozen at -80°C for clinical chemistry analysis.
Volume: Up to 20 tests can be performed on 500 uL. Minimum sample size for Individual test is 150 uL.