Question 75

Moving the tubes in a figure eight motion 4 to 8 times after collection is the correct method to prevent clotting.

Inverting tubes in a figure eight motion helps to ensure that the anticoagulant is evenly mixed with the blood, which is essential for preventing clotting.

A) Shaking the tubes 4 to 8 times after collection

Shaking the tubes can cause hemolysis or damage to blood cells, which can lead to inaccurate test results. This method is not recommended as it may not effectively mix the anticoagulant with the blood.

B) Moving the tubes in a figure eight motion 4 to 8 times after collection

This method is the preferred technique as it gently mixes the blood with the anticoagulant without causing damage to the blood cells. The figure eight motion promotes even distribution and proper mixing, which is crucial for preventing clot formation.

C) Rolling the tubes between the palms of the hands 4 to 8 times after collection

While rolling tubes can mix the contents, it may not provide the same thorough mixing as the figure eight motion. This technique may also lead to inconsistent results if not performed uniformly.

D) Passing the tubes from hand to hand 4 to 8 times after collection

Passing tubes from hand to hand may not achieve adequate mixing of the anticoagulant with the blood. This method lacks the necessary motion to ensure that the contents are thoroughly mixed, potentially leading to clot formation.

Conclusion

The method of moving the tubes in a figure eight motion is the most effective for ensuring proper mixing of anticoagulant and blood, thereby preventing clotting. All other methods either risk causing hemolysis, lead to inconsistent mixing, or do not effectively integrate the anticoagulant, making them less suitable for this critical task.