Effect of Classical Music on Depth of Sedation and Induction Propofol Requirements in Dogs

Abstract

The main objective of this prospective, randomized, blind, cross-over experimental study was to evaluate the effect of classical music on the depth of sedation and propofol requirements for the induction of anaesthesia in dogs. Twenty dogs were involved, and each was subjected to three different treatments with a 3-month gap: Chopin music, Mozart music, and no music, via loudspeakers. The dogs were premedicated with acepromazine and butorphanol by intramuscular injection, and anaesthesia was induced using propofol intravenously. To compare the depth of sedation and propofol requirements for the induction of anaesthesia among the different treatments, we utilized non-parametric tests (Kruskal-Wallis test) for the depth of sedation due to a slight deviation from the normal distribution and parametric (ANOVA) for propofol requirements. When exposed to music (Chopin or Mozart), dogs exhibited deeper sedation and required less propofol for their intubation compared to the no-music treatment (p < 0.05). Exposure to classical music had a positive impact on the level of sedation, and more profound central nervous system depression seemed to contribute to approximately 20% lower propofol dose requirements for tracheal intubation. Therefore, classical music during the preoperative period appeared to exert a beneficial effect, at least when applying the specific pre-anaesthetic medications used in the present study.

Keywords: acepromazine; butorphanol; dog; music; propofol; sedation.

Figure 1

Boxplot of the sedation score among the 3 treatments (CM, MM and NM) 90 min after auditory stimulation and 45 min after premedication. The horizontal line inside the boxes denotes the median value, while the upper and lower whisker bounds denote the maximum and minimum values. The differences between the CM–NM and the MM–NM treatments were statistically significant (p < 0.01).

Figure 2

Means plot with ± SD whisker of propofol dose (mg/kg) for tracheal intubation in dogs among the 3 treatments (CM, MM, NM). The differences between the CM–NM and the MM–NM treatments were statistically significant (p < 0.01).