9.3 Venipuncture Across the Lifespan: Children, Older Adults & Other Special Populations

Venipuncture Across the Lifespan: Children, Older Adults & Other Special Populations

NCCT's phlebotomy tasks include "perform venipuncture on patients of all ages" and "take precautions for patients with special needs (for example, mastectomy, IVs, bleeding disorders)." Section 9.1 teaches the standard adult technique and Section 9.2 covers site restrictions such as mastectomy, IV lines, and fistulas. This section explains how to adjust for age and for other patient factors that change equipment, positioning, communication, and aftercare.

Pediatric Patients

Choosing the Method

• For infants under about 12 months, most small-volume tests are collected by heel stick (Section 10.1).
• Venipuncture on infants and young children requires special training. Common sites are the antecubital veins and the back of the hand. Scalp, femoral, and jugular veins are used only by physicians or specially trained staff.

Protecting Blood Volume

Children have much less blood than adults, roughly 75 to 80 mL per kilogram. A 10-kg toddler has only about 800 mL in total. Removing too much, especially with repeated draws in the hospital, can cause iatrogenic anemia.

• Published safety limits reviewed by the World Health Organization (2011) generally keep blood drawn for testing to about 1% to 5% of total blood volume within 24 hours (and up to about 10% over 8 weeks). For the 10-kg toddler, 1% to 5% is roughly 8 to 40 mL.
• Use pediatric or partial-draw tubes and draw only the volume the laboratory needs. Many labs post minimum volumes for pediatric tests.
• Many facilities track the cumulative volume drawn from pediatric patients; follow that log.

Equipment

• A 23-gauge butterfly (or 25-gauge for very small veins, used carefully because of hemolysis risk) with small-volume tubes, or a small syringe with gentle suction to avoid collapsing tiny veins.
• Pediatric tourniquets or a gentler tourniquet technique, and colorful bandages if the child is not allergic to adhesive.

Preparing the Child and Family

• Identify the child with the parent or guardian and the ID band (Section 3.1), and obtain the guardian's permission.
• Explain in words that fit the child's age. Be honest: say "You will feel a quick pinch," never "This won't hurt." A broken promise makes every later procedure harder.
• Let the parent stay if possible, and offer distraction (toys, bubbles, videos, counting). Topical numbing creams can be used when ordered and applied in advance by the nurse.
• Immobilization: a parent or trained helper holds the child in a comfort position (for example, the child sitting on the parent's lap, chest to chest, with the arm held gently but firmly). Never let a child's arm move freely during a draw.
• Afterward, praise the child for helping, whatever happened, and check the site carefully.

Older Adults

Aging brings thin skin, fragile and rolling veins, and less padding around vessels.

• Choose equipment for fragile veins: a 22- or 23-gauge butterfly and smaller-volume tubes, or a syringe, reduce vein collapse.
• Tourniquet: apply it loosely enough to avoid pinching the skin, or over a thin sleeve or gauze, and remove it as soon as blood flows.
• Anchor the vein firmly but gently; loose skin lets veins roll.
• Positioning: arthritis or contractures may stop the arm from straightening. Support the arm on a pillow and never force a joint.
• Communication: face the patient, speak clearly, allow time, and confirm identity carefully if the patient has hearing loss or memory problems.
• Aftercare: hold pressure until bleeding stops and avoid adhesive tape on thin skin. Use a self-adherent wrap applied without tension, or paper tape. Remove any adhesive slowly and low to the skin to prevent skin tears.

Patients on Anticoagulants or With Bleeding Disorders

Patients taking warfarin, heparin, direct oral anticoagulants, or high-dose aspirin, and patients with hemophilia, low platelet counts, or liver disease, bleed longer.

• Use good technique to avoid probing, which enlarges the puncture.
• Apply direct pressure until bleeding completely stops, often several minutes longer than for other patients, and check the site before bandaging.
• Do not let the patient bend the elbow over the gauze (Section 9.1).
• If bleeding continues despite several minutes of pressure, keep holding pressure and notify the nurse. Watch for a developing hematoma.

Bariatric Patients

• The cephalic vein on the thumb side of the antecubital area is often the easiest to feel, because less fat covers it (Section 9.1).
• A longer needle (1.5 inches) may be needed to reach a deeper vein.
• Use a bariatric-length tourniquet, or a blood pressure cuff inflated to about 40 mm Hg as a tourniquet.
• Palpate carefully; landmarks are harder to find, and pressing too firmly with the needle holder can push it deeper than intended.

Anxious, Needle-Phobic, or Combative Patients

• Ask whether the patient has ever fainted during a blood draw. If so, have the patient lie down for the draw.
• Talk the patient through each step, and offer distraction.
• For patients who are confused or combative, get a second person to help hold the arm steady. A competent patient who clearly refuses is not held down; stop and notify the nurse (Section 14.1).

Patients in Isolation

Don the required PPE before entering (Section 1.3). Bring only the supplies you need, use a disposable or single-patient tourniquet, and leave it in the room. Place labeled tubes in a clean biohazard bag held by a helper outside the door or according to policy, so the outside of the bag stays clean.

Clinical Trap: The Honest Pinch

A PCT tells a frightened 6-year-old, "This won't hurt at all," then performs the draw. The child screams and refuses every procedure for the rest of the admission. Honest, age-appropriate preparation, a comfort hold with a parent, and distraction would have kept trust intact.