New artificial oxygen carriers made of pegulated polymerised pyridoxylated porcine haemoglobin (P(4)Hb).

Oxygen-carrying plasma expanders are designed for use as iso-oncotic 'blood substitutes' to combat oxygen deficiencies caused by blood loss. In contrast, a hypo-oncotic artificial oxygen carrier can be added to existing blood - as a 'blood additive'. It has potential therapeutic use for deficiencies of oxygen which are not entailed by blood (volume) lack, and can therefore not be treated by a 'blood substitute', e.