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.

Hypertonic saline and pentoxifylline prevent lung injury and bacterial translocation after hemorrhagic shock

Previous reports have shown beneficial effects of pentoxifylline (PTX) and hypertonic saline (HS) in the treatment of hemorrhagic shock. We compared the effects of these solutions to those of conventional lactated Ringer's (LR) treatment on bacterial translocation (BT), lung injury and total and differential cell count in the bronchoalveolar lavage fluid (BAL) after hemorrhagic shock. Rats (280-330 g) were bled to a MAP of 35 mmHg for 1 h and then randomized into 4 groups: LR (3x shed blood); HS (7,5% NaCl, 4 mL/kg); LR+PTX (25 mg/kg) and SHAM (no shock, no treatment). Additionally, total shed blood was reinfused. At 24 h lung injury was analyzed by a pathologist blinded to the groups, and a score was calculated. BT was determined by microbiological cultures of mesenteric lymph node complex. BAL was performed on a separate set of animals that received the same treatments. Lung score was significantly higher in LR group (11.5+/-1.4) as compared to HS (6.8+/-0.9), and PTX treated animals (7.2+/-0.9). The percentage of neutrophils in the BAL of LR animals (15.8%) was also significantly higher as compared with HS (5.25%) and PTX groups (9.72%). BT was noted in 50% of rats for LR group, 30% for PTX, 10% for HS and 0% for sham group. HS and PTX reduced BT and lung injury after hemorrhage. Attenuation of lung injury could be the result of less neutrophil infiltration into the lungs of HS and PTX treated animals. LR resuscitation caused pronounced lung injury and BT.