Comparison of hypertonic saline/dextran versus hypertonic saline/hetastarch for resuscitation of hypovolemia.

In the present study, we compare resuscitation of bled sheep with hypertonic saline/dextran or hypertonic saline/hetastarch. Unanesthetized sheep were subjected to 2 h of hemorrhagic hypotension and then resuscitated with 200 ml of 7.5% NaCl solution made up to include either 6% dextran 70 (Macrodex) or 6% hetastarch (Hespan). Both solutions provided an immediate and sustained improvement in arterial pressure and cardiac output. The hypertonic saline/dextran provided a slightly better overall response as mean arterial pressure, cardiac output and central venous pressure were higher in the dextran group at all times post resuscitation. However, only the differences in arterial pressure and initial plasma volume expansion were statistically significant. The somewhat better response to hypertonic saline/dextran may be explained by the higher oncotic pressures generated by dextran compared to equal concentrations of hetastarch.