Choice A reason:

Choice A Reason:
The red top tube is typically used for serum determinations in chemistry, serology, and blood bank. It contains no additive or may contain a clot activator. The red top tube is not the first choice for capillary puncture order of draw because it is designed for tests that require serum and not whole blood.

Choice B Reason:
The lavender top tube is used for whole blood hematology determinations, as it contains EDTA as an anticoagulant. According to the order of draw for capillary punctures, the EDTA tube should be collected first to ensure adequate volume and accurate hematology test results. This makes the lavender top tube the correct choice for the first collection in this scenario.

Choice C Reason:
The light blue top tube contains sodium citrate and is used for coagulation tests. In venipuncture, it is drawn after the blood culture bottle and before other tubes to prevent contamination with additives from other tubes. However, for capillary punctures, it is not the first choice as hematology tests take precedence.

Choice D Reason:
The royal blue top tube is used for trace element, toxicology, and nutrient determinations². While it may be used for lead and toxicology screens mentioned in the question, it is not the first tube to be drawn in a capillary puncture sequence. The EDTA tube (lavender top) is drawn first to prevent clotting and ensure accurate CBC results.

Choice A reason:
Expired tubes may lose their vacuum, which is necessary to draw the correct volume of blood into the tube. The vacuum in blood collection tubes ensures that the correct amount of blood is drawn. If the vacuum is lost, the blood will not be drawn into the tube properly, which can lead to underfilling and affect the test results.

Choice B reason:
Hemoconcentration refers to an increase in the concentration of cells and solids in the blood, usually because of a loss of plasma. While this can occur due to prolonged tourniquet application or dehydration, it is not directly caused by the use of expired tubes.

Choice C reason:
Hemolysis is the destruction of red blood cells, which can release hemoglobin and other intracellular components into the plasma. It can be caused by physical damage, such as from a needle during blood draw, but is not a consequence of using expired tubes. However, if an expired tube causes improper blood draw due to loss of vacuum, it could indirectly lead to hemolysis due to multiple attempts to draw blood.

Choice D reason:
An elevation of the red blood cell count would not be directly caused by using expired tubes. The red blood cell count is determined by the body's production and destruction of red blood cells, not by the collection method or equipment used.