Some metabolic and hormonal changes associated with general anaesthesia and surgery in the horse.

This research article explores how three different anesthetic techniques affect metabolic and hormonal changes in horses undergoing surgery. The study found that the combination of acepromazine, glyceryl guaiacolate, and a ‘half-dose’ of thiopentone resulted in the least physiological and metabolic disturbances.

Research Methods

• The researchers observed three anesthetic techniques on healthy Thoroughbred or Thoroughbred-type horses.
• The methods involved combinations of the following drugs:
  • Acepromazine, thiopentone, and suxamethonium
  • Acepromazine, glyceryl guaiacolate, and a ‘half-dose’ of thiopentone
  • Xylazine and ketamine
• All horses were then maintained on halothane vaporized in oxygen and nitrous oxide during surgery.
• The horses underwent either laryngeal or body surface surgery.

Data Collection and Measurement

• The study measured heart rate, packed cell volume (a measure of the volume percentage of red blood cells in blood), blood glucose and lactate levels, plasma non-esterified fatty acids, insulin, and cortisol levels.
• These measurements were collected before, during, and after surgery.

Key Findings

• The research found the most significant metabolic and hormonal changes occurred immediately after anesthetic induction. These changes varied according to the anesthetic technique used.
• The anesthetic technique which combined acepromazine, glyceryl guaiacolate, and a ‘half-dose’ of thiopentone, caused the least variations in physiological and metabolic measures.

Implications

• This study can potentially guide veterinarians in developing anesthetic protocols for equine surgeries. By choosing anesthetic techniques that minimize metabolic and hormonal disruptions, recovery might be quicker and smoother.