The authors have studied the efficiency of new blood substitutes (polyoxidin and mafusol) in complex infusion-transfusion therapy in operations on lungs. During surgical interventions these medications were administered in doses of 717.0 +/- 30.0 ml and 914.0 +/- 74.0 correspondingly, and one day after the operation--400 ml each. Operational blood losses were 1.25 +/- 0.9 l. It was found out that polyoxidin and mafusol have executed positive influence upon various factors of pathophysiological mechanisms, and thus were effective in complex treatment of blood losses or shock states.