Common Mistakes: Performing Venipuncture and Capillary Puncture
These are the specific ways this task goes wrong on the job — not hypothetical edge cases, but patterns that cause real documentation errors, billing problems, or patient safety issues.
Leaving the tourniquet on for more than about a minute, which can hemoconcentrate the sample and affect certain lab values.
Labeling tubes away from the patient (at a desk, after the next patient has already started), risking a mislabeled or mismatched specimen.
Not wiping away the first drop of a capillary sample, which can be diluted with tissue fluid and skew results.
Drawing tubes in the wrong order when multiple additives are needed, which can cause cross-contamination between additives.
How the Quality Checkpoints Prevent These
Every mistake above is caught by one of this task's quality checkpoints — the habit of checking these consistently is what actually prevents the error, not just knowing it exists.
- ✓
Patient identity is verified against the requisition before any collection starts.
- ✓
Tube order of draw is followed correctly when multiple tubes are needed for one venipuncture.
- ✓
Tubes are labeled at the patient's bedside, immediately after collection — never pre-labeled or labeled later.
- ✓
Bleeding has visibly stopped before the site is bandaged and the patient is released.
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