Giving Sets, Filters and Compatible Fluids

The right equipment and compatible fluids prevent haemolysis, clotting in the line, air embolism, hypothermia and delays. Using the wrong fluid or the wrong set can make a safe unit harmful.

Safety preparation.

• Confirm that the intravenous access is patent and secure, and has been flushed with 0.9% sodium chloride.

• Check the expiry and integrity of the giving set.

• Confirm that the warmer, pump or rapid infuser is validated for blood and in date for service.

Special groups.

• Children and neonates: smaller cannulas, syringe drivers or paediatric sets with the correct filters, and slower rates.

• Older adults and fragile veins: central access or intraosseous access when peripheral access fails.

• Patients on cold agglutinin disease or large volumes: warmers.

Blood giving set. A set with an integral filter of about 170 to 200 micrometres, for red cells, whole blood, plasma, cryoprecipitate and platelets. Change the set after each platelet transfusion if the hospital requires, and at least every 12 hours of continuous use, and sooner when blocked or when the manufacturer specifies a shorter limit. Do not use a set designed for crystalloid.

Other filters. Leucocyte filters at the bedside are not needed when the component is leucodepleted before storage. Microaggregate filters are not routine. Do not use a filter that removes platelets for platelet concentrates.

Intravenous access.

• Adults: an 18 to 20 gauge cannula is usual for routine transfusion, and a 14 to 16 gauge cannula for rapid transfusion.

• Children: 22 to 24 gauge is usual and slower flow is accepted.

• Central lines and intraosseous access are acceptable in emergencies.

• Do not pass blood through a line with another infusion running.

Pressure devices. A pressure bag or rapid infuser can be used with a suitable cannula for rapid transfusion. Avoid high pressure with narrow cannulas, which can cause haemolysis. Do not exceed the pressure stated by the manufacturer (usually up to 300 mmHg).

Blood warmers.

• Indications: rapid infusion of more than about 50 mL/kg/hour in adults, or about 15 mL/kg/hour in children, exchange transfusion, large volume neonatal transfusion, and cold agglutinin disease.

• Requirements: a validated blood warmer with a temperature alarm, with output not exceeding 41 degrees Celsius.

• Never warm blood in a water bath of uncontrolled temperature, microwave or radiator. Do not use a warmer for platelets.

Compatible fluids.

• Only 0.9% sodium chloride is safe in the same line as red cells.

• Do not use 5% dextrose, which causes haemolysis and clumping.

• Do not use solutions containing calcium in the same line as red cells, because calcium can overcome citrate and cause clots. Give calcium through a separate line.

• Calcium free balanced crystalloids may be compatible when the hospital has validated them.

• Do not add drugs to the bag or give them through the same line.

Setting up.

1. Choose the cannula and the set to suit the urgency, the patient's build and the product.

2. Prime the blood giving set with 0.9% sodium chloride, or with the blood itself.

3. Connect the set to the unit using an aseptic technique, and avoid air.

4. Start slowly, and check for leaks, kinks and extravasation.

5. Attach a warmer when indicated, positioned close to the patient, and check the temperature alarm.

6. Flush the line with 0.9% sodium chloride at the end of the transfusion, and before and after each unit when different components are given.

If the line blocks or the cannula tissues. Stop, assess the site, resite the cannula, and use a new set if needed. Do not squeeze the bag. If the delay is long, follow the time limit of 4 hours from leaving storage.

For massive transfusion. Use large bore access in two sites, a rapid infuser with a warmer, and give calcium through a separate line.

Complications. Haemolysis from high pressure, dextrose or heat, clot in the line, air embolism, hypothermia from cold products given rapidly, extravasation, infection of the cannula site, and hyperkalaemia from rapid infusion of old red cells.

Documentation. Type of access, site, set and filter used, warmer use, flush and any problems.

Quality assurance. Warmers are validated and serviced, set changes are audited and staff are trained in the right fluids. Incidents with incompatible fluids are reported.