High School

Which of the following is the most appropriate step when performing a capillary puncture?

A. Hold both ends of the capillary tube
B. Select the index finger of the right hand
C. Allow bubbles to form in the capillary tube
D. Apply firm pressure to the selected finger
E. Discard the first drop of blood

Answer :

When performing a capillary puncture, also known as a fingerstick, it is important to follow proper procedures to ensure patient safety and obtain an accurate blood sample. The most appropriate step in this multiple-choice question is:

(E) Discard the first drop of blood.

Here's why this step is critical and what it entails:

  1. Purpose: The first drop of blood is usually contaminated with tissue fluids that can affect the test results. Discarding it helps ensure that the sample collected consists mainly of blood, providing more reliable test outcomes.

  2. Procedure: After making a small puncture on the finger, the first drop should be wiped away gently with a clean gauze pad or tissue. Subsequent drops are less likely to contain tissue fluids and provide a cleaner sample for analysis.

  3. Context: This practice is common in medical settings, such as when testing blood glucose or performing other point-of-care testing where a precise reading is essential.

This step emphasizes the importance of precision and care in medical procedures to enhance the accuracy of diagnostic tests which is critical in a medical setting.