How should a tube with additives be mixed?

How should a tube with additives be mixed?

• A. Shake vigorously
• B. Invert 6-8 times
• C. Vortex 30 seconds
• D. Roll between palms

Answer: (B)

The essential idea is to mix the blood evenly with the additive without causing damage to the sample. Inverting the tube several times after collection distributes the additive throughout the blood gently and reliably. Six to eight inversions strike a balance: they ensure thorough mixing so the anticoagulant or additive can work properly, while minimizing shear forces that could hemolyze cells or create troublesome foaming. Shaking vigorously can cause cell damage and foam that interferes with tests, rolling between the palms doesn’t reliably mix the additive, and vortexing is too forceful for routine blood collection tubes. Therefore, inverting the tube six to eight times is the best practice for proper mixing.

The essential idea is to mix the blood evenly with the additive without causing damage to the sample. Inverting the tube several times after collection distributes the additive throughout the blood gently and reliably. Six to eight inversions strike a balance: they ensure thorough mixing so the anticoagulant or additive can work properly, while minimizing shear forces that could hemolyze cells or create troublesome foaming. Shaking vigorously can cause cell damage and foam that interferes with tests, rolling between the palms doesn’t reliably mix the additive, and vortexing is too forceful for routine blood collection tubes. Therefore, inverting the tube six to eight times is the best practice for proper mixing.