Effect of environmental noise and music on dexmedetomidine-induced sedation in dogs.

BACKGROUND: Previous studies in human patients suggest depth of sedation may be affected by environmental noise or music; however, related data in domestic animals is limited. The objective of the current study was to investigate the effect of noise and music on dexmedetomidine-induced (DM- 10 µg/kg, IM) sedation in 10 dogs.

METHODS: In a crossover design, post-DM injection dogs were immediately subjected to recorded human voices at either 55-60 decibel (dB) (Noise 1) or 80-85 dB (Noise 2); classical music at 45-50 dB (Music); or background noise of 40-45 dB (Control+). Control- included IM saline injection and exposure to 40-45 dB background noise. Sedation was assessed via monitoring spontaneous behavior and accelerometry (delta-g) throughout three 20-min evaluation periods: baseline, noise exposure, and post-treatment. Sedation was further assessed during two restraint tests at 30 min (R1) and 40 min (R2) post-injection. A mixed model for crossover design was used to determine the effect of noise exposure and time on either spontaneous behavior scores or delta-g. The restraint scores were analyzed using a two-way repeated measures ANOVA.

RESULTS: Spontaneous behavior scores indicated less sedation during Noise 2 compared to Control+ (P = 0.05). R2 restraint scores for all DM treatments except Noise 2 indicated significantly higher sedation than Control- [C+ (P = 0.003), M (P = 0.014) and N1 (P = 0.044)].

DISCUSSION: Results suggest that the quality of sedation is negatively impacted by high-intensity noise conditions (80-85 dB), but exposure to music did not improve sedation in this population of research dogs.