Authors: Niedzwiedz Artur, Slawuta Piotr, Zak Agnieszka, Slowikowska Malwina, Siwinska Natalia, Rykała Marta, Nicpon Jozef
Journal: Journal of equine veterinary science
Summary
# Editorial Summary Equine asthma syndrome, a chronic allergic inflammatory condition predominantly affecting mature horses, frequently triggers secondary respiratory acidosis through alveolar hypoventilation, yet the underlying ionic mechanisms driving this acid-base disturbance remain poorly characterised in clinical practice. Researchers compared arterial and venous blood samples from 16 asthmatic Warmbloods and mixed-breed horses against 10 healthy controls, measuring conventional parameters (pH, pO₂, pCO₂, HCO₃⁻) and electrolytes alongside calculated values including anion gap and strong ion difference (SIDa and SIDe) using the Stewart approach. Asthmatic horses demonstrated compensatory respiratory acidosis alongside significantly elevated sodium concentrations, reduced chloride levels, and substantially higher SIDa and SIDe values compared with controls—findings that indicate meaningful ionic redistribution affecting water dissociation equilibrium during the disease process. These alterations suggest that SIDa and SIDe calculations offer diagnostic and monitoring potential beyond conventional blood gas interpretation, potentially guiding more targeted therapeutic intervention in asthmatic horses experiencing acid-base complications. Equine practitioners managing respiratory disease should consider the broader ionic context of acid-base disturbance, though the clinical utility of Stewart-derived parameters warrants validation through larger prospective studies before routine implementation in practice.
Read the full abstract on PubMed
Practical Takeaways
- •Respiratory acidosis in horses with asthma involves measurable changes in electrolyte concentrations (sodium and chloride) that go beyond traditional acid-base parameters
- •The Stewart model parameters (SIDa and SIDe) may offer additional diagnostic information beyond standard blood gas analysis for managing asthmatic horses
- •Monitoring ionic balance alongside conventional respiratory parameters could help optimize treatment strategies for asthmatic horses with respiratory complications
Key Findings
- •Horses with severe equine asthma developed systemic compensatory respiratory acidosis with elevated pCO2 and reduced pH in arterial blood
- •Serum sodium concentration was significantly higher and chloride significantly lower in asthmatic horses compared to controls
- •Strong ion difference values (SIDa and SIDe) were significantly elevated in asthmatic horses, indicating ionic changes affecting water dissociation
- •SIDa and SIDe calculations using the Stewart model may provide diagnostic and therapeutic utility in managing respiratory acidosis in horses