Patient Preparation and Identification
What you must understand
Identification is the highest-consequence skill in phlebotomy. Use two independent identifiers - typically full name plus date of birth or medical record number - and match them to the requisition. For inpatients, also inspect the armband. Ask the patient to state and spell their name rather than asking "Are you Mrs. Smith?", which invites a yes from a patient who did not hear or understand. Never identify by room number, bed card, chart position, or the appearance of the person.
Label tubes at the bedside, in the patient's presence, after collection - never before the draw and never from memory later. An unlabeled or mislabeled tube must not be tested; it is recollected.
Preparation includes knowing the test requirements: fasting status (commonly 8–12 hours, water allowed), timing of drug levels and glucose tolerance tests, and the effect of the patient's position and activity. Explain the procedure, obtain consent, and confirm any restrictions. Choose the site thoughtfully - the median cubital vein is preferred; avoid an arm with an IV line, dialysis fistula or graft, mastectomy with lymph node removal, lymphedema, hematoma, scarring, burns, or active infection. Note that contrast dye may require a delay before drawing from that arm.
Preparation also controls pre-analytical error: a tourniquet left on too long or vigorous hand clenching raises potassium, lactate, and protein by hemoconcentration.
Traps
- Using a leading question instead of open-ended verification.
- "The patient was asleep, so I confirmed with the spouse" - family cannot substitute for the patient's own identifiers.
- Pre-labeling tubes in the supply room.
Worked example: a patient says "I'm here for blood work." That is not identification. Say: "Please state your full name and date of birth," then compare both to the requisition and armband before any needle is opened.