Sevoflurane

Sevoflurane In Dogs & Cats: Uses, Dosage and Side Effects

Overview

• The mechanism of action of volatile anaesthetic agents is not fully understood.

Uses of Sevoflurane

• Induction and maintenance of anaesthesia.

Dose of Sevoflurane in Dogs and Cats

Dogs, Cats:

• The expired concentration required to maintain surgical anaesthesia in 50% of recipients is about 2.5% in animals (minimum alveolar concentration).
• Administration of other anaesthetic agents and opioid analgesics reduces the dose requirement of sevoflurane; therefore, the dose should be adjusted according to individual requirements.
• 6–8% sevoflurane concentration is required to induce anaesthesia in unpremedicated patients.

Side Effects of Sevoflurane in Dogs and Cats

• Causes dose-dependent hypotension that persists over time.
• Sevoflurane’s impact on respiration is dose-dependent and comparable to isoflurane, being more depressant than halothane.
• Crosses the placental barrier, affecting neonates delivered by caesarean section.
• When degraded by soda lime, it produces nephrotoxic compounds, particularly Compound A, in rats.
• Conditions accelerating degradation (e.g., low gas flows, high absorbent temperatures, and high sevoflurane concentrations) should be avoided in lengthy operations.
• No studies in dogs have shown Compound A to accumulate in concentrations causing renal toxicity.
• Caution is needed with sevoflurane use due to its potential hypotensive effects, impact on neonates, and generation of nephrotoxic compounds under specific conditions.

Contraindications of Sevoflurane in Dogs and Cats

• No information is available.

Some Notes:

• Sedatives, opioid agonists, and nitrous oxide decrease the concentration of sevoflurane needed for surgical anesthesia.
• Sevoflurane has a similar impact on the duration of action of non-depolarizing neuromuscular blocking agents as isoflurane, resulting in greater potentiation than halothane.
• Sevoflurane, a potent and highly volatile anesthetic, should only be administered using a calibrated vaporizer.
• It is less soluble in blood compared to halothane and isoflurane, leading to quicker induction and recovery from anesthesia.
• Sevoflurane has a milder smell than isoflurane, making it well-tolerated during induction using chambers or masks in small dogs and cats.
• The required concentration of sevoflurane depends on the overall anesthesia protocol and should be adjusted based on clinical assessment of anesthetic depth.
• Rapid recovery follows the cessation of sevoflurane administration, sometimes accompanied by signs of agitation.
• Unlike halothane, sevoflurane does not sensitize the myocardium to catecholamines to the same extent.