Order of draw and tube selection
Using the correct tube order prevents cross-contamination between additives. Collectors should verify orders against the requisition before the first needle stick.
Mixing and timing
Some tubes require immediate inversion. Delayed processing or hemolyzed samples can invalidate results and force patients to repeat uncomfortable draws.
Chain of custody for special tests
Toxicology, genetic, and temperature-sensitive specimens need additional documentation. Mobile teams should arrive with appropriate coolers, forms, and courier handoff procedures.
