Venous Blood Sampling

Bedside

Indications

  1. Routine investigations
  2. Cross-match / culture
  3. Drug levels
  4. Coagulation

Contraindications

  1. AV fistula limb
  2. Limb with lymphoedema / mastectomy
  3. Site infection

Equipment

  1. Tourniquet, alcohol wipe, gauze
  2. Vacutainer holder + 21G needle or butterfly
  3. Blood bottles (correct order of draw)
  4. Sharps bin

Technique

  1. Identify patient, explain procedure, consent
  2. Tourniquet 10 cm proximal — never >1 min
  3. Palpate vein (antecubital fossa, dorsum of hand)
  4. Clean 30 s, allow to dry
  5. Insert needle bevel up at 15–30°, advance into vein
  6. Order of draw: cultures → blue (coag) → red/gold (serum) → green (heparin) → purple (EDTA) → grey (fluoride)
  7. Release tourniquet before removing needle
  8. Pressure 1–2 min, label bottles at bedside, dispose sharps

Complications

  1. Haematoma, infection
  2. Nerve injury (esp. AC fossa)
  3. Arterial puncture
  4. Haemolysis (rough technique, wrong order)

Aftercare

  1. Document samples sent + time
  2. Chase critical results

Clinical pearls

  1. Always label at bedside — never pre-label or label later (never event)
  2. If difficult, use USS or call senior
  3. Blood culture: 2 sets, separate sites, before antibiotics

Perform under supervision until competent. Follow local SOPs and consent policy.

WardRound

WardRound

Clinical Decisions in Seconds