Frusemide results in an extracellular to intracellular fluid shift in horses.

The research is focused on the effects of a diuretic called Frusemide on horses, particularly its impact on the distribution of fluid within the horse, initiating a shift of fluid from the extracellular to intracellular compartments which has significant implications for performance and clinical practices.

Study Objective and Methods

• The study aimed to elucidate the effects of frusemide on the shifts of fluid between extracellular and intracellular compartments within the horse’s body.
• To this end, two groups of horses were administered with different doses of frusemide (1 mg/kg body mass in one group and 2 mg/kg body mass in the other).
• The total body water (TBW), extracellular fluid volume (ECFV), and plasma volume (PV) were measured using deuterium oxide (D2O), sodium thiocyanate (NaSCN), and Evans blue dilution respectively.
• To assess the change in ECFV, the plasma protein concentration was measured, and the infusion/dilution of NaSCN was repeated.

Study Results

• The research found frusemide to prompt a reduction in the TBW in horses within 120 minutes post-administration.
• The losses in ECFV were almost twice as much as the TBW losses 120 minutes following the administration of frusemide, suggesting a shift of fluid in excess of TBW loss to the intracellular space (ICFV).

Conclusions

• The results show that frusemide causes a net shift of fluid, including water and electrolytes, from the extracellular to intracellular compartments.
• The research is the first to characterise such fluid shifts occurring within horses given frusemide.
• The shift of fluid to the intracellular compartments carries significant implications for both the performance of horses in activities (like racing) and in clinical practices, indicating the need for further comprehensive studies on the subject.