Final answer:
The correct order for filling microcontainers for a capillary blood draw depends on the specific tests ordered and the healthcare facility's protocol. Without additional details, it's generally recommended to start with the lavender-top tube for hematology tests, but the medical assistant should always follow their organization's specific guidelines.
Step-by-step explanation:
When a medical assistant is given a requisition for a capillary blood draw, the order of filling the microcontainers is essential due to the possibility of cross-contamination and the need for specific additives to perform certain types of analyses. However, based on the provided requisition options, some guidance may be derived. The lavender-top tube, which typically contains EDTA as an anticoagulant, is commonly used for hematology tests, such as CBC (complete blood count). The light-blue-top tube contains sodium citrate as an anticoagulant and is used for coagulation tests, requiring the preservation of the coagulation factors. The red-top tube typically lacks an anticoagulant and is used for serology and blood bank tests, and the yellow-top tube contains an anticoagulant and is usually designated for blood culture specimens.
For capillary collections, it is generally important to collect tubes with additives before those without to prevent clotting of the sample. Additionally, tubes requiring a full draw should be collected before those that do not to ensure proper ratios of blood to additive. However, capillary blood collection order is not as standardized as venipuncture due to the small volumes and may vary based on the patient's condition and the specific tests ordered. Without specific protocol from the requisition details, it is typically safe to start with the lavender-top tube for hematology tests, but the correct answer depends on the test priorities and the organization's specific protocol, which the medical assistant should follow.