NHA Certified Clinical Medical Assistant (CCMA)Clinical Patient CareMedium
A medical assistant is performing a capillary puncture for a blood glucose test. Which of the following actions should the MA take to increase blood flow to the puncture site?
- APuncture the finger on the palmar surface.
- BMassage the finger from tip to base.
- CApply a tourniquet to the finger.
- DWarm the patient's hand prior to puncture.
Show answer & explanationAnswer & explanation
Correct answer: D. Warm the patient's hand prior to puncture.
Warming the patient's hand or finger increases blood flow to the capillaries, making it easier to collect a sufficient sample. Massaging from base to tip can cause hemolysis or tissue fluid contamination, and a tourniquet is not used for capillary punctures. Puncturing the palmar surface can be more painful and is not the recommended site.
Why the other options are wrong
- A. The palmar surface of the finger is not the recommended puncture site due to increased nerve endings and potential for bone injury; the lateral sides are preferred.
- B. Massaging the finger from tip to base can push tissue fluid into the sample, causing dilution and inaccurate results.
- C. A tourniquet is not used for capillary punctures and can cause stasis, leading to inaccurate results.
Capillary Puncture Blood Flow Enhancement
Techniques used to improve blood flow to the capillary puncture site to ensure an adequate and high-quality blood sample.
- Warm the site (warm compress or rubbing).
- Position hand below heart level.
- Avoid excessive squeezing or 'milking' the finger.
- Proper site selection (lateral sides of 3rd or 4th finger).
Memory trick: Warm Hand, Happy Flow