The Effect of Hetastarch on Serum Colloid Oncotic Pressure in Hypoalbuminemic Dogs

The purpose of this study was to determine the duration of action of a single dose of hetastarch, a synthetic colloid, in hypoalbuminemic dogs. Thirty hypoalbuminemic dogs (albumin concentration, < or = 2.0 g/dL) received 1 dose of hetastarch each, with an average dose of 18.1 mL/kg. Doses ranged from 7.7 to 43.9 mL/kg, with the majority of doses (n = 26) in the range of 10 to 25 mL/kg. Dogs were allotted to one of several groups: all dogs, dogs with acute gastrointestinal protein loss, dogs with chronic gastrointestinal protein loss, all dogs with gastrointestinal protein loss, and dogs with nongastrointestinal protein loss. Colloid oncotic pressure was measured immediately before and immediately after hetastarch administration, and 12 hours after hetastarch administration. There was a significant (P < .001) increase in the mean colloid oncotic pressure after hetastarch treatment in all groups, except in the group with acute gastrointestinal protein loss. Twelve hours after hetastarch treatment, the mean colloid oncotic pressure had decreased significantly (P < .001) from the immediate post-treatment value in all groups, except in dogs in the groups with acute and chronic gastrointestinal protein loss. Twelve hours after hetastarch treatment the mean colloid oncotic pressure was not significantly (P < .001) different from the baseline mean colloid oncotic pressure in any of the groups. Twenty-three dogs (77%) survived their illness and were sent home, whereas, 7 (23%) died or were euthanized. The effect of a single dose of hetastarch on raising colloid oncotic pressure in dogs with hypoalbuminemia decreases significantly within 12 hours of administration, and is no longer significantly above baseline values. We conclude that multiple dosing is necessary to prolong the beneficial effects of hetastarch.