A phlebotomist should explain the procedure prior to venipuncture to:

Choice A Reason:
Taking the specimen temperature before 4 minutes is the correct procedure according to the Department of Transportation (DOT) guidelines. The DOT Rule 49 CFR Part 40 Section 40.65 states that the temperature of the specimen must be checked no later than four minutes after the employee has given the specimen. The acceptable temperature range is 32–38 °C/90–100 °F, which helps to verify the validity of the specimen.

Choice B Reason:
Taking the specimen temperature at 5 minutes is not within the DOT guidelines. The temperature must be taken before 4 minutes have passed to ensure the specimen's integrity and to comply with the regulatory requirements.

Choice C Reason:
At 15 minutes, the temperature check would be too late. The DOT guidelines specify that the temperature should be checked no later than four minutes after collection to ensure the specimen has not been tampered with and is within the acceptable temperature range.

Choice D Reason:
After 30 minutes, the temperature of the urine specimen would not reflect the body temperature at the time of collection, which is necessary for the validity of the test. This delay could allow for the temperature to fall outside of the acceptable range, potentially invalidating the specimen.

Choice A Reason:
Wrapping the site with a heel warmer for 30 minutes is a preparatory step before the heel stick procedure. It is used to increase blood flow to the area to make the collection easier. However, it is not the action to take after the blood has been collected. The heel warmer should be removed before performing the heel stick.

Choice B Reason:
Wiping away the first drop of blood is the correct procedure. The initial drop may be contaminated with tissue fluids or alcohol if the site was cleaned prior to the stick, which can affect the accuracy of the test results. Therefore, the first drop should be wiped away, and subsequent blood should be used for the PKU test.

Choice C Reason:
Keeping a pressure dressing on the site for the entire day is not necessary and is not part of the standard heel stick procedure. After the blood is collected, a small bandage is typically applied to stop any bleeding. The site should be monitored for a short time for any signs of continued bleeding or bruising, but a pressure dressing for the day is excessive.

Choice D Reason:
Targeting the central arch area of the foot for the heel stick is incorrect and can be harmful. The recommended area for a heel stick is the lateral portions of the heel to minimize discomfort and avoid injury to the bone or nerves. The central arch area should be avoided to prevent potential harm.