A phlebotomist needs to collect a PT (Prothrombin Time) from a patient with a difficult vein. Which of the following is the best tube for the draw?

Choice A Reason:
Povidone-iodine is an antiseptic used for skin disinfection before and after surgery. It has a broad spectrum of antimicrobial activity, but it is not the preferred choice for capillary blood collection due to the potential interference with certain laboratory tests. Povidone-iodine needs to be completely dried to avoid hemolysis of the sample, which can affect test results.

Choice B Reason:
Hand sanitizer is generally used for hand hygiene and not for the disinfection of the site for blood specimen collection. While it is effective in killing germs on the skin, it contains emollients and gelling agents that can contaminate the blood sample and interfere with laboratory tests.

Choice C Reason:
70% isopropyl alcohol is the most commonly used disinfectant for aseptic technique in capillary blood collection. It is effective against a broad range of microorganisms and evaporates quickly, leaving no residue that could contaminate the sample. It is important to allow the alcohol to dry completely before performing the puncture to prevent stinging and sample dilution.

Choice D Reason:
A 10% chlorine bleach solution is not typically used for skin disinfection in blood collection due to its harshness and potential to cause skin irritation and damage. It is more commonly used for disinfecting surfaces and equipment in healthcare settings.

Choice A reason:
Holding the two slides at a 90-degree angle is not the correct technique for performing a blood smear. This angle is too steep and would not allow the blood to spread thinly across the slide, which is necessary for creating a quality smear that can be examined under a microscope.

Choice B reason:
Allowing the blood drop to clot slightly before performing the smear is not advisable. Clotting can interfere with the spread of the blood and the formation of a monolayer, which is essential for accurate microscopic examination. The blood should be fresh and anticoagulated to prevent clotting.

Choice C reason:
Holding the slides at a 30-degree angle is the correct technique for performing a blood smear. This angle allows the spreader slide to push the blood drop smoothly across the patient slide, creating a thin, even layer of blood that is ideal for microscopic analysis. The angle, speed, and pressure must be consistent to achieve a quality smear.

Choice D reason:
Allowing the blood drop to clot completely before performing the smear would make it impossible to create a smear. Clotted blood cannot be spread into a thin layer, which is necessary for microscopic examination of the blood cells.