Performing Venipuncture or Capillary Puncture

Step-by-Step Procedure

1. 1

   Verify the patient's identity using two identifiers (name and date of birth) and confirm the test order matches the patient.

2. 2

   Select the appropriate equipment: evacuated tube system for venipuncture, or a lancet and microcollection tubes for a capillary/fingerstick draw.

3. 3

   Apply the tourniquet no more than 1 minute before the draw, select a vein by palpation, and cleanse the site with the appropriate antiseptic.

4. 4

   Perform the venipuncture at the correct angle (15-30 degrees for most veins), and fill tubes in the correct order of draw to avoid cross-contamination between additives.

5. 5

   For a capillary draw, warm the site if needed, puncture the correct area (e.g., lateral fingertip, not the central pad), and wipe away the first drop before collecting.

6. 6

   Release the tourniquet before withdrawing the needle (or as soon as blood flow is established), apply pressure to the site, and bandage once bleeding stops.

7. 7

   Invert additive tubes the number of times specified for that tube type, and label every tube immediately at the patient's side — never pre-label or label after walking away from the patient.

Quality Checkpoints

• ✓

  Patient identity is confirmed with two identifiers before any specimen is collected.

• ✓

  Order of draw is followed correctly when filling multiple tubes.

• ✓

  Tubes are labeled at the bedside/chairside immediately after collection, never before or after leaving the patient.

• ✓

  Tourniquet time stays under 1 minute to avoid hemoconcentration affecting results.

Common Mistakes

• ⚠

  Pre-labeling tubes before the draw — if the wrong patient's tube gets used, this creates a serious misidentification risk.

• ⚠

  Leaving the tourniquet on too long, which can falsely elevate certain lab values.

• ⚠

  Drawing tubes out of order, allowing an additive from one tube to contaminate the next.

• ⚠

  Massaging or squeezing a fingerstick site aggressively, which dilutes the sample with tissue fluid and skews results.

On-the-Job Tips

• →

  The standard order of draw (blood culture, then coagulation/citrate, then serum/SST, then heparin, then EDTA, then fluoride/oxalate) protects every sample in the sequence — follow it even when you're only drawing two tubes.

• →

  If a vein is hard to find, a warm compress and proper positioning solves more problems than repeated blind attempts.

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