Final answer:
The appropriate tubes for a skin puncture when testing WBC, RBC, glucose, and electrolytes are lavender and gray. The lavender tube contains EDTA for complete blood count (CBC) tests and the gray tube is used for glucose testing and also accommodates electrolyte measurement.
Step-by-step explanation:
The correct color tubes to use for a skin puncture in this case would be lavender and gray. Lavender-top tubes contain EDTA, an anticoagulant, which is used for complete blood count (CBC) tests, measuring WBC and RBC. A gray-top tube contains sodium fluoride as a preservative and an anticoagulant (potassium oxalate), which is commonly used for glucose testing. Electrolytes are also typically measured using blood from a gray-top tube.
Capillary blood collection like skin punctures are less invasive and required when venipuncture cannot be conducted, suitable for small sample amounts. A skilled phlebotomist can perform this task following the specific guidelines and using the correct equipment to obtain accurate test results in the medical lab.
Each blood test has specific tube colors associated with them due to the types of additives that either preserve the blood, prevent clotting, or serve other purposes. These color-coded tubes ensure that the blood sample is processed correctly for the type of test ordered.