Preparing administering Infusions Mark Tomlin Consultant Pharmacist Critical

Preparing & administering Infusions Mark Tomlin Consultant Pharmacist: Critical Care Southampton University Hospitals NHS Trust

Why Parenteral? • • Rapid onset of action Achieving high blood/tissue concentrations Reliability Initial loading

Whether an alternative route should be considered? • Injections are expensive and hazardous • IM, SC may be painful or have erratic absorption • Oral route may be unavailable, but consider NG, NJ, PEG/J • Nausea, vomiting, diarrhoea, ileostomy, gut surgery • Rectal inappropriate clinically/pharmaceutical • Transdermal

What route ? • Central • Or peripheral

What route ? • Central • Measuring CVP, PAWP • Concentrates in fluid restricted patients • Too irritant peripherally • Slow and risky to gain access – needs experience & practice • Or peripheral • Easy and safer access • Large volumes • Familiar route

Where to prepare? Treatment Room Toilet Theatres Aseptic Suite in Pharmacy (CIVAS)

When to prepare ? Immediately before Use Before they go to theatre 24 hours before you need it Before the weekend A week before you need it

How to prepare & administer • • • Reconstituting Cefuroxime 750 mg vial Administering Metronidazole 500 mg IV Preparing Rifampicin IV Diluting Propofol Piggy – backing Y –site into a running infusion How to find the correct diluent Lignocaine, Saline, Water, Potassium

What IV fluid - 1 ? • Crystalloid • or colloid?

What IV fluid - 1 ? • • Crystalloid Most familiar Cheap May need large volumes • Relatively slow increase in CVP • Will move out of vascular space • or colloid? • HDU/ITU and critically ill only • Expensive • Rapid increase in CVP • Small volumes • Water redistribution out of tissues

What IV fluid - 2 ? • • • Saline, Glucose or Dextrose/saline What strength ? The list of choices Serum sodium Diabetes Acid-base

Fluid balance • A simple question of input equal to output • A straight question of 3 L in, and 3 L out • A question of giving sufficient fluid to achieve 1 mg/kg/hr urine output • A complex balance of forces to achieve a urine output of about 1 mg/kg/hr (assuming normal renal function) without causing heart failure, pulmonary or peripheral oedema • Achieving an adequate urine output (accounting for other losses) with a maintenance dose, and giving treatment doses to sustain BP&CO • Giving a fluid challenge to ask the question about whether the patient is adequately filled (BP, CRT)

Problems with infusions and fluids • Forget it is still running ! • Incorrect calculation Wrong dose Wrong rate Wrong concentration (Flolan) Wrong infusion device or Wrong set-up • Changes - equipment, rates & concentrations • The F word and when to use it?