Hydroxyethyl starch 6% (130/0.4) ameliorates acute lung injury in swine hemorrhagic shock

Traumatic hemorrhage induces acute lung injury. The aim of this study was to assess whether lactated Ringer's solution or 6% hydroxyethyl starch 130/0.4 would have different effects on acute lung injury following hemorrhagic shock.

Twenty healthy pigs (19 ± 2 kg) were subjected to hemorrhage and were randomly allocated to two groups: Group A (10 pigs) who received lactated Ringer's solution and Group B (10 pigs) who received hydroxyethyl starch 130/0.4. Hemodynamic response and serum lactate were measured at predetermined phases. Four hours after fluid resuscitation animals were euthanized. Lungs were harvested, and tissue samples were collected. Focal thickening of the alveolar membranes, vascular congestion, number of activated neutrophils, alveolar edema, interstitial neutrophil infiltration, intraalveolar infiltration, and alveolar hemorrhage were assessed. Each feature was given a score from 0 to 3 (0 = absence, 3 = severe). The wet/dry ratio was also calculated, and with the use of Evans blue dye extravasation method, capillary permeability was assessed.

The total histology score of Group A differed significantly from that of Group B, being significantly lower in Group B animals P = 0.048. The wet/dry weight ratio was significantly higher in the lactated Ringer's group (median [range]) (Group A, 5.1 [0.5]; Group B, 4.9 [0.3]; P = 0.009). The Evans blue dye extravasation method was utilized to study the lung capillary permeability. The animals in Group B showed a marked reduction in microvascular capillary permeability compared with the animals in Group A (Group A, 58.5 [21] mg/g; Group B, 51.5 [14] mg/g; P = 0.017).

Our study indicates that resuscitation after hemorrhagic shock with hydroxyethyl starch 130/0.4 led to less lung edema and less microvascular permeability in this swine model.