Red cells

Red cell transfusion is indicated to increase the oxygen delivering capacity of the blood when acute or chronic anaemia contributes to inadequate oxygen delivery to tissues. The standard red cell component supplied in the UK contains about 20 ml of residual plasma. The rest is replaced by a saline solution containing added adenine, glucose and mannitol. (This is referred to as SAGM, SAGMAN, Adsol or optimal additive solution.) The resulting blood component is officially termed ‘red cells, leucocyte-depleted, in additive solution’. In this book, the term ‘red cell unit’ is used to denote the red cells from one standard blood donation.

Dosage is usually expressed in terms of number of red cell units. This is an unsatisfactory measure due to the variability of the haemoglobin and red cell content of red cell units that is permitted within the current specification.

Table 2 Red cells in additive solution

	mean	sd	95%CI	range
Volume ml	282	± 32	284−285	180−350
Haemoglobin g per pack	55	± 8	58−59	35−72
Haematocrit %	57	± 3	54.6−55.1
Red cells ml per pack	161	± 25
Plasma ml per pack	17	± 10		4−25
Anticoagulant CPDA₁ ml	4
Additive solution SAGM ml	100
Storage	Up to 35 days at +2°C to +6°C
Compatibility requirement	Must be compatible with recipient’s ABO (and usually RhD type): ABO blood groups and antibodies
Dosing guide	Dose of 4 ml/kg (one pack to 70 kg adult) typically raises venous Hb concentration by about 10 g/l Paediatric use (see Transfusion of the newborn infant)
Administration	Use blood administration set; complete the infusion within four hours of removal from controlled temperature storage (see Table 2)
Variants	CMV negative (see Prevention of CMV transmission) Irradiated (see Prevention of TA-GvHD)
Cautions	Risks to recipients (see Adverse effects of transfusion)
Source: NBS and SNBTS routine QA data

[Table 2 resources: View large format or download as Word^™ document]