MP4OX is being developed as an ischemic rescue therapy to perfuse and oxygenate tissues at risk during hemorrhagic shock. MP4OX is a pegylated hemoglobin-based colloid designed to improve perfusion and target delivery of oxygen to ischemic tissues. This study will evaluate safety and efficacy of MP4OX treatment, in addition to standard therapy, in trauma patients suffering from lactic acidosis due to severe hemorrhagic shock.