DO NOT USE FOR CLINICAL PRACTICE
Please use current guidelines available on the UHNM intranet for patient treatment
Please use current guidelines available on the UHNM intranet for patient treatment
Venepuncture is the preferred method of blood sampling for term babies and causes less pain than heel prick
INDICATIONS
- Blood sampling in a baby without indwelling arterial line, or when sampling from arterial line or capillary sampling is inappropriate
EQUIPMENT
- Cleaning solution or cleaning swab – follow local infection control policy
- Appropriately labelled blood bottles and request cards
- Non-sterile gloves
- Adhesive dressing
- 23 G blood sampling needle or needle-safe cannula
- Do not use a broken needle
- Sterile gauze/cotton wool to apply to wound post-procedure
- Sharps container
PROCEDURE
Preparation
- Wash hands and wear gloves (see Infection prevention guideline)
- Second person employs containment holding and gives sucrose
- immobilisation is crucial to baby’s safety whilst undergoing phlebotomy, and to success of procedure
- Identify suitable vein (typically back of hand or foot)
- Place paper towels under limb to avoid blood dripping onto bed linen
Insertion and sampling
- Apply hand pressure around limb to distend vein
- Clean the puncture site then do not touch again
- Place thumb on skin slightly distal to proposed puncture site
- Hold needle at 10–20° angle and puncture skin
- Advance needle toward vein. Resistance may diminish slightly as needle enters vein and blood will be seen to flow
- Collect required volume taking care to mix but not shake blood
- When sampling complete, release the pressure from around the limb, place gauze/cotton wool over insertion point and withdraw needle
- Maintain pressure on site until bleeding ceases
Complications
- Inability to obtain specimen due to:
- inappropriate choice of vein
- thrombosed vein (due to previous/repeated attempts)
- inexperienced operator
- baby shocked, cold or dehydrated causing vasoconstriction
Unsuccessful attempts
- Adhere strictly to a limit on number of attempts
- If no satisfactory sample collected after 2 attempts, seek second opinion as to whether to make a further attempt or cancel procedure
- Defer to a more experienced operator
- Venous distension:
- use warm pack to encourage vasodilation and venous filling
- Transillumination of limb can help identify suitable vein
Avoid:
- Veins close to an infection, bruising and phlebitis
- Thrombosed veins
- Oedematous limbs – danger of stasis of lymph, predisposing to complications e.g. phlebitis and cellulitis
- Areas of previous venepuncture – build-up of scar tissue can cause difficulty accessing vein and result in pain
- Sampling from potential IV infusion site or long line vein (e.g. cubital fossa or long saphenous) whenever possible
Haemolysis risk factors
- Use of <23 G needle, or too large a gauge for vessel
- Drawing blood specimens from IV or central line
- Under-filling tube – ratio of anticoagulant to blood >1:9
- Reusing tubes that have been refilled by hand with inappropriate amounts of anticoagulants
- Mixing tube too vigorously
- Failing to let alcohol/disinfectant dry
- Using too great a vacuum, e.g. using too large a tube or syringe
- Squeezing can cause haemolysis and elevate serum potassium
Completion and organisation
- Keep track of all needles used and dispose of them in sharps container
- do not re-sheath needle
- Dispose of rubbish and clean tray
- Remove gloves and wash hands
- Label all samples and investigation forms at cot side
- Arrange for transfer of samples to laboratory
- Document in patient notes
SAFETY OF PRACTITIONER
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Wear well-fitting gloves during procedure to prevent contamination from potential blood spills
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gloves will not prevent needle stick injury, but the wiping effect of glove on needle may reduce volume of blood to which hand exposed
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Discard used needles directly into sharps container – do not re-sheath
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Report any incident/accident linked to needle or sharp injury immediately, and seek assistance; start PEP as soon as possible, following protocols (>72 hr, PEP not effective)