Abstract

Background:
Neuromuscular blocking agents are widely used in veterinary anesthesia to facilitate tracheal intubation and provide optimal surgical conditions. Quantitative neuromuscular monitoring (NMM) enables accurate evaluation of neuromuscular effects while ensuring cardiovascular safety in anesthetized dogs.

Aim:
This study aimed to quantify the neuromuscular effects, therapeutic effectiveness, and cardiovascular safety of rocuronium and atracurium during quantitative neuromuscular monitoring of dogs under ambulatory anesthesia.

Methods:
A total of 18 healthy adult dogs were randomly divided into two groups. One group received 0.6 mg/kg IV of rocuronium, and the other received 0.5 mg/kg IV of atracurium after the induction of isoflurane anesthesia, with each group consisting of nine dogs. Neuromuscular transmission was quantified using calibrated train-of-four (TOF) acceleromyography. Onset time, duration of action, and recovery time to a TOF ratio ≥ 0.9 were measured concurrently with continuous monitoring of heart rate, mean arterial pressure, and oxygen saturation.

Results:
The use of rocuronium resulted in a significantly faster onset of neuromuscular block compared with atracurium (p < 0.001), enabling rapid tracheal intubation. No significant differences were found between the two groups regarding the duration of action and recovery time. During the anesthesia period, cardiovascular parameters remained stable and comparable between the groups, and only one dog in the atracurium group experienced a minor, transient adverse effect.

Conclusion:
The results suggest that both drugs are potent and do not harm dogs. In addition, rocuronium is a better option for quick procedures, whereas atracurium can be used in situations where it is not anticipated that the patient will be able to respond to reversal agents or has compromised organ function, due to its predictably less discomfort during the recovery phase.

Key words: Ambulatory anesthesia; Atracurium; Dogs; Neuromuscular blockade; Rocuronium.