Oleander toxicosis in equids: 30 cases (1995-2010).

The study provides an analysis of the effects and outcome-related factors of oleander poisoning in horses (equids), revealing frequent complications in the gastrointestinal tract, heart, and kidneys, with the key cause of death being cardiac dysfunction.

Study Methodology

• The researchers conducted a retrospective analysis of 30 equids who had shown detectable levels of oleandrin—a toxic compound in oleander—in their serum, plasma, urine, or gastrointestinal fluids.
• A medical records database was used to identify these cases, excluding those that had taken cardiac glycoside drugs but still had detectable concentrations of digoxin in the serum.
• The team calculated descriptive statistics for various factors including medical history, physical examination, laboratory analysis, and necropsy variables.
• A logistic regression analysis was done to identify factors from the physical examination and laboratory analysis that were significantly associated with the outcome of the cases.

Results

• It was found that 3 out of 30 (10%) equids died before or just after arrival at the hospital.
• Of the remaining 27, 23 (85.2%) had gastrointestinal abnormalities, 19 (70.4%) were diagnosed with azotemia—an excess of nitrogen compounds in the blood—and cardiac arrhythmia was detected in 18 (66.7%).
• The overall mortality rate was 50%, reducing to 44.4% for equids that were hospitalized.
• Cardiac dysfunction was identified as the most common cause of death.
• Survival rates were found to be lower for equids with cardiac arrhythmias compared to those without and decreased with increasing hematocrit (Hct) and blood sugar levels. Conversely, survival odds increased with higher serum chloride concentrations and prolonged hospitalization.

Conclusion

• The study concluded that oleander poisoning in equids often resulted in simultaneous issues in the horses’ gastrointestinal tract, cardiac, and renal systems.
• Therefore, consideration should be given to oleander intoxication as a differential diagnosis in cases of colic in equids in regions where oleander is prevalent, especially if azotemia or cardiac arrhythmias are concurrently detected.