Prevalence of Electrolyte Disturbances and Perianesthetic Death Risk Factors in 120 Horses Undergoing Colic Surgery.

This study investigates the prevalence of electrolyte imbalances and the risk factors that contribute to anesthesia-related deaths in horses undergoing surgery for colic. The authors find that imbalances are common in this scenario and identify several factors that raise the likelihood of death.

Methodology

• The researchers examined the medical records of 120 horses that met the study’s criteria.
• They collected and analyzed data on the horses’ demographic characteristics, whether or not electrolyte imbalances occurred, and any other complications that unfolded during surgery.
• This data was evaluated using both univariate and multivariate logistic regression models, which are statistical processes that relate the effects of multiple variables to a certain outcome—in this case, the incidence of electrolyte imbalances and the chances of death during anesthesia.

Findings

• The most commonly observed electrolyte imbalance was hypocalcemia (a deficiency of calcium in the bloodstream), which appeared in 52.5% of cases, followed by hypokalemia (having too little potassium), observed in 30% of cases.
• The researchers discovered a link between the administration of salbutamol—a drug used to treat breathing problems—and the occurrence of hypokalemia (P = .045).
• Of the 120 horses, 46 (38.3%) died during the perianesthetic period. This mortality rate is comparable to those documented in previous research.

Risk Factors

• The study identified several risk factors linked with death during anesthesia, including a long duration of anesthesia (P = .001), heavy body weight (P = .020), existing gastric reflux prior to anesthesia (P = .021), and intraoperative complications such as tachycardia (rapid heart rate) (P = .043) and acidosis (excessive acid in the body fluids) (P = .025).

Recommendations

• Acknowledging their findings, the authors recommend stabilizing the animals’ hemodynamics—or the forces involved in circulating blood—before anesthesia to prevent intraoperative tachycardia, which increases the risk of death.
• This study suggests that larger horses and those with gastric reflux ahead of anesthesia are at greater risk of death.
• It also advises caution when using salbutamol during surgery, as it may trigger hypokalemia.