Cannulas Flashcards
What sites should be avoided for cannulation?
- Infected/ broken skin
- Smaller, superficial veins
- Sites below venepuncture site - may cause extravisation
- Sclerosed vein (hardened vein)
- Side of mastectomy
What cannula size is used for emergencies?
- Orange = 14G
- Grey = 16G
What cannulas are used for normal blood transfusion and infusion of large volumes?
- White = 17G
- Green = 18G
What cannulas are used for medication and fluids?
- Pink = 20G
- Blue = 22G
Why should the smallest cannula size that is appropriate for treatment be used?
Large cannula placed in a vein that is too small will impede blood flow, cause pain , scar tissue and chemical irritation.
What are the common modes of infection?
- Hub colonisation: poor ANTT in pre/ post insertion of PVC
- Operator’s microflora: poor hand hygeine / no gloves
- Patient’s microflora: poor cleaning of insertion site
- Contaminated on insertion - touching key parts of PVC
- Contaminated infusates: poor ANTT when connecting syringes/ infusion sets
- Haematogenous: when infection enters bloodstream
What are the basic steps of cannulation?
- Collect required equipment - draw up flush and prime extension set before reaching patient
- Check patient details, allergies and indication
- Position patient correctly with arm extended\
- Gel hands and don clean apron, apply tourniquet and check for preferred site
- Once found, release tourniquet and decontaminate site with 70% IPA wipe for 30 secs, and allow 30 secs for air drying
- Whilst air drying, don non-sterile gloves and prepare cannula
- Re-apply tourniquet and allow vein to refill - DO NOT REPALPATE
- Anchor vein down, then insert cannula at 15-30 deg
- Observe for primary flashback, then flatten cannula and advance further 2-3mm
- Retract needle 2-3mm and observe secondary flashback
- When seen, continue to advance cannula all the way to the hub
- Release tourniquet, then occlude vein and hold down cannula wing with 2nd digit
- Remove needle and dispose in sharps immediately
- Apply extension set
- Secure cannula using appropriate dressing.
- Flush via extension set - looking for extravisation. Reclamp before removing syringe
What happens in post insertion care?
- Cannula and site must be check 8 hourly
- Remove cannula if no longer required - or after 72 hrs
- Check for signs of phlebitis, occlusion and extravisation after each administration of drug
- Needless connectors should be removed
What is VIP score?
Visual Infusion Phlebitis score:
0 = IV site appears healthy
1= One of: pain, erythema, swelling
2= Two of : pain, erythema, swelling
What are some causes of phlebitis?
- Acid pH
- High osmolarity e.g. 50% dextrose
- Loosely fixed cannula
- Pressure at cannula site
- Length of time in situ
- Cannula size
