Abstract
Blood transfusion is given according to haemoglobin thresholds aimed at restoration of arterial oxygen‐carrying capacity. Patient survival after severe haemorrhagic shock depends on restoration of microvascular perfusion, tissue oxygen delivery, endothelial function and organ integrity. We investigated a novel crystalloid fluid designed for tissue oxygen delivery, Oxsealife®, with components that generate microvascular nitric oxide and scavenge reactive oxygen species generated during ischaemia–reperfusion injury. The amount of dissolved oxygen in blood progressively increased during step‐wise in vitro haemodilution with this fluid, suggesting that the oxygen solubility coefficient of blood is dynamic, not static. We performed a pilot safety and efficacy study to compare resuscitation with this novel crystalloid vs. whole blood transfusion in a swine haemorrhagic shock model with animals bled to an arterial lactate oxygen debt target. Despite contributing no haemoglobin, viscosity nor oncotic potential, resuscitation with Oxsealife after severe haemorrhagic shock restored central haemodynamic parameters comparable to stored allogeneic blood transfusion. Tissue perfusion, oxygenation and metabolic outcomes were equivalent between treatment groups. Increased consumption of bicarbonate in animals given Oxsealife suggested greater capillary recruitment and enhanced clearance of acidic tissue metabolites. Serum markers of organ function, animal activity during recovery and histological analysis of tissue morphology and endothelial glycocalyx integrity confirmed functional recovery from haemorrhagic shock. We conclude that recovery of tissue oxygen delivery and organ function after haemorrhagic shock may not be dependent on treatments that increase haemoglobin levels. Oxsealife shows promise for treatment of severe haemorrhagic shock and may reduce the requirement for allogeneic blood products.