Effects of hetastarch 130/0.4 on plasma osmolality, colloid osmotic pressure and total protein in horses anaesthetised for elective surgical procedures.

This study examined the effects of two solutions, lactated Ringer’s solution (LRS) and hetastarch 130/0.4 (HES), on the osmolality, colloid osmotic pressure, and total protein levels in anesthetized horses during surgery. The research found that HES increases osmolality and temporarily maintains colloid osmotic pressure better than an equal volume of LRS.

Research Design and Experiment

• The experimental design involved a group of 18 healthy horses which were put under inhalation anaesthesia.
• These horses were then divided into two groups, each containing 9 horses. One group was given LRS, while the other was administered HES.
• The dosage given was between 4-6 ml/kg, starting from anaesthesia induction up until 60 minutes into the procedure. Following this, all horses were given LRS.
• The colloid osmotic pressure (COP), total protein (TP) and plasma osmolality (OSM), were then measured at different intervals: before premedication (baseline), postinduction and 30, 60, 90, and 120 minutes into the procedure.

Study Findings

• The results showed that at the beginning of the experiment (baseline), there was no difference between the two groups in terms of COP, OSM, and TP.
• All horses, regardless of the group they belonged to, showed a decrease in TP at all measured time points after induction.
• For the group that was administered HES, OSM increased after 30, 60, 90, and 120 minutes from the baseline.
• COP decreased in the LRS group from 30 to 120 minutes and in the HES group at 90 and 120 minutes.
• On average, the COP was higher in the HES group than in the LRS group at 30 (18.8±0.5 vs 16.3±0.4 mmHg), 60 (19.1±0.5 vs 15.9±0.4 mmHg) and 90 (17.4±0.5 vs 15.4±0.5 mmHg) minutes into the procedure.
• The study concluded that infusing HES for 60 minutes increases OSM and transiently maintains COP when compared with administering an equal volume of LRS in anaesthetised horses.

Implications of the Study

• This research provides valuable insights on how these two solutions work in a surgical context.
• This could help vets make better decisions about what solutions to use during surgery, potentially improving the outcome and postoperative recovery for the animals.
• However, more research may be needed to validate these results and determine the longer-term effects of these solutions.