Which of the following samples is used to measure blood pH and blood gases?

A. An adult patient is watching a demonstration on the proper use of a meter-dose inhaler: This is related to managing a respiratory condition, not directly to communicable disease prevention.
B. An adult patient is being shown how to safely lift a heavy object: This pertains to body mechanics and injury prevention, not communicable disease prevention.
C. An older adult patient is listening to an explanation of risks and benefits of the flu vaccine: Although the flu vaccine helps prevent disease, the specific focus is not directly on communicable disease prevention strategies.
D. A school-age patient is being taught about cough etiquette: Teaching cough etiquette is a direct method of preventing the spread of communicable diseases.

A. Add thixotropic gel to the tube after venipuncture: Thixotropic gel is used in specific tubes for separating serum or plasma from blood cells and should be added during the manufacturing process, not after venipuncture.
B. Place the tubes in the centrifuge to chill after venipuncture to separate blood cells: Tubes should not be chilled before centrifugation unless specified by the test requirements. Most tubes are centrifuged at room temperature.
C. Invert additive tubes multiple times after filling the tube: Inverting additive tubes multiple times ensures proper mixing of the additive with the blood, which is crucial for accurate test results.
D. Mix the anticoagulant in the tube after filling the tube: The anticoagulant should be mixed by inverting the tube immediately after filling it, not after the fact.
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