Superiority of hypertonic saline/dextran over hypertonic saline during the first 30 min of resuscitation following hemorrhagic hypotension in conscious swine

Abstract

We compared the effectiveness of intravenously administering hypertonic saline/dextran (HSD; 7.5% NaCl in 6% Dextran-70, n = 6) to hypertonic saline (HS) alone (7.5% NaCl, n = 8) in rectifying detrimental effects of hemorrhage on cardiovascular function. Chronically instrumented conscious swine were hemorrhaged 37.5 ml/kg over 60 min. If untreated, this model is 100% lethal within 60 min. Swine received HSD or HS at 4 ml/kg. Functional variables were measured before and at 5, 15, and 30 min following treatment. HSD produced a significantly greater plasma volume expansion than HS alone (13.6 compared to 9.9 ml/kg). Over 30 min expansion was sustained in pigs receiving HSD but pigs receiving HS regressed. Cardiac index (CI) increased for both treatments, being greater with HSD, 104 ml/kg/min, compared to HS alone, 46 ml/kg/min. Neither group fully sustained these elevated values post-treatment, but remained consistently greater than values after hemorrhage; however, the difference in CI between treatments was maintained. Oxygen delivery showed a trend similar to that of CI. We conclude that resuscitation with HSD is superior to HS in improving cardiovascular function over the first 30 min after hemorrhage.