A comparison of the effects of a 4% modified fluid gelatin and a 6% hydroxyethyl starch on haemodilution, colloid osmotic pressure, haemostasis and renal parameters in healthy ponies.

The research compares the effects of modified fluid gelatin (MFG) and hydroxyethyl starches (HES) on blood dilution, osmotic pressure, blood clotting, and kidney function in healthy ponies. It finds that both MFG and HES can be useful for volume expansion and osmotic support, with no notable adverse effects on haemostasis or renal parameters.

Methodology

• In the study, a randomised crossover experiment using three treatments (one with HES, and two with different quantities of MFG) was carried out on six healthy ponies. The treatments were separated by a 1 week period to allow the efects of one treatment to dissipate before the next was administered.
• Several parameters were measured before and after each treatment including haematocrit (the proportion of blood occupied by red blood cells), platelet count, total serum protein, colloid osmotic pressure (COP), thromboelastography (TEG, a test used to assess the efficiency of blood coagulation), prothrombin time (PT, a measure for blood clotting), activated partial thromboplastin time(aPTT, a measure of the coagulation pathways), and fibrinogen concentration (an indication of coagulation potential of blood).
• Additionally, renal parameters were monitored based on urine tests including serum creatinine concentration, urine specific gravity (USG), urine protein:creatinine ratio (UPC), urine γ-glutamyltransferase:creatinine ratio (UGC) and urine sediment examination (USE).

Findings

• Results showed that all treatments led to significant haemodilution and increases in COP.
• The MFG treatment delivered at a higher concentration (Treatment C) had a significantly greater effect on the ponies’ haematocrit than the other two treatments. It also led to a decrease in platelet counts, which was more pronounced compared to the MFG treatment at a lower concentration (Treatment B).
• No significant differences were observed among various coagulation tests such as TEG parameters, PT, aPTT or fibrinogen concentration across the treatments.
• Regarding renal parameters, no variations were found in serum creatinine concentration, UPC, UGC, USG and USE between pre- and post-treatment measurements.

Conclusion

• The study concludes that modified fluid gelatin could be a viable alternative to HES for volume expansion and oncotic support since neither MFG nor HES was associated with clinically significant adverse impact on haemostasis or renal parameters in healthy ponies.