Resuscitation of hemorrhagic shock with hypertonic saline/dextran or lactated Ringer's supplemented with AICA riboside.

Anesthetized and ventilated swine were bled 23 ml/kg (34% of calculated blood volume) to a mean arterial pressure < 50 mm Hg. After 60 min, a bolus of either 7.5% hypertonic saline/6% dextran 70 (HSD, 4 ml/kg x 5 min) or lactated Ringer's (LR, 32 ml/kg x 5 min) was infused i.v. LR (25-30 ml/kg) was administered to all animals for the next 60 min. Amino imidazole carboxamide riboside (AICAR), which increases endogenous adenosine in ischemic tissues, was added to the initial bolus and the subsequent LR (10 mg/kg bolus + 0.5 mg/kg x 60 min) in half the study population. At 2 hr post-shock, hematocrit, urine output, arterial pressure, pulmonary artery pressure, pulmonary capillary wedge pressure, portal venous O2 saturation, and pulmonary arterial O2 saturation were similar in all groups. With HSD vs. LR, cardiac outputs and stroke volumes were each significantly higher, while right atrial pressures and pulmonary vascular resistances were each significantly lower, which is consistent with augmented cardiac contractility with HSD. Furthermore, systemic oxygen consumptions were significantly higher, and intracranial pressures were each significantly lower with HSD. Nevertheless, no variables were far outside the normal range in either group. The addition of AICAR to LR and HSD eliminated the difference in intracranial pressure, systemic oxygen consumption, reduced heart rate by 30-40 beats/min during the first hour of resuscitation, and increased stroke volume by 20-30%.(ABSTRACT TRUNCATED AT 250 WORDS)