Initial management of severe hemorrhage with an oxygen-carrying hypertonic saline solution.

We tested the hypothesis that the combination of polymerized bovine hemoglobin (PBHg) with hypertonic saline may be beneficial for the initial management of hemorrhagic shock in 22 mongrel dogs (15 +/- 1 kg) bled to a mean arterial pressure (MAP) of 40 mm Hg in 5 min and maintained at this level for 45 min (shed blood volume approximately 50 ml/kg). Animals were treated with a 4 ml/kg bolus over 4 min of one of the following fluids: whole blood, 7.5% NaCl (HS), 13 g/dl of PBHg, or 7.5% NaCl combined with polymerized bovine hemoglobin (HS-PBHg). No additional intervention was performed, and the animals were followed for 60 min after treatment. PBHg and HS-PBHg produced a sustained, significant increase in MAP. Cardiac output was transiently increased only after HS and HS-PBHg. A partial increase in superior mesenteric artery blood flow was observed, particularly after HS-PBHg. We concluded that small volumes of PBHg alone restore MAP, but not blood flow. The combination of PBHg with hypertonic saline provides improvements in cardiac output and mesenteric blood flow, suggesting a potential benefit for the initial management of major blood loss.