Fluid resuscitation improves hemodynamics without increased bleeding in a model of uncontrolled hemorrhage induced by an iliac artery tear in dogs.

Background: Fluid resuscitation administered before hemorrhage control for trauma victims sustaining penetrating abdominal injury is controversial. Our objective was to evaluate intra-abdominal blood loss and hemodynamic and metabolic effects of no fluid resuscitation, small-volume 7.5% sodium chloride/6% dextran-70 (HSD), or large-volume lactated Ringer's (LR) solution during intra-abdominal vascular injury and uncontrolled hemorrhage. Methods: In pentobarbital-anesthetized dogs (n = 26, 17 ± 0.3 kg), a suture was placed through the common iliac artery to produce a 3-mm tear when the exteriorized suture lines were pulled after incision closure. Dogs were randomized to three groups, according to the treatment used after 20 minutes of uncontrolled hemorrhage: controls, no fluid resuscitation (CT group) (n = 6); the HSD group (4 mL/kg over 4 minutes, n = 6); and the LR group (32 mL/kg over 15 minutes, n = 6). After 40 minutes of uncontrolled bleeding, animals were killed, and intra-abdominal blood loss was measured. Results: Eight dogs died from severe hemorrhagic shock before randomization and were excluded. After 20 minutes, animals presented lower blood pressure (∼ 35 mm Hg), low cardiac output ( 1.0 L/min/m 2 ), and metabolic acidosis (pH 7.23, base excess -9 mmol/L). After HSD and LR solution, arterial pressure presented a transient increase, but remained below baseline. Two animals died before the end of the experiment, both in the LR group. Cardiac index was partially improved in the LR and HSD groups, whereas the CT group sustained a low-flow state. There were no significant differences between groups regarding intra-abdominal blood loss (CT group, 47.8 ± 5.9 mL/kg; HSD group, 41.7 ± 2.3 mL/kg; and LR group, 49.4 ± 0.7 mL/kg). Concusion: Fluid resuscitation with either large-volume LR solution or small-volume HSD, during uncontrolled hemorrhage from intra-abdominal vascular injury, produced hemodynamic and metabolic benefits, without additional blood loss, whereas no fluid resuscitation was associated with sustained low cardiac output and hypotension.