Figure 3.

A blinded observer examined videotapes taken at induction, preeuthanasia, and euthanasia and scored levels of (A) agitation (increased and altered activity) and (B) dyspnea (increased respiratory effort) on a scale of 0 to 3 (0, none; 1, mild; 2, moderate; 3, severe). For both agitation and dyspnea, mice anesthetized with isoflurane displayed the highest mean scores at euthanasia. Regardless of treatment, all groups displayed significant (P < 0.05) dyspnea at the time of euthanasia compared with either preeuthanasia or induction levels. NA, no applicable data. (A) Δ, Significant (P < 0.05) increase in agitation compared with values at preeuthanasia and euthanasia time points; Φ, significant (P < 0.05) increase in agitation compared with that of with mice induced with acepromazine; *, significant (P < 0.05) increase in agitation compared with that of respective preeuthanasia score; Ω, significant (P < 0.05) increase in agitation at euthanasia compared with that of mice treated with 20% V/min CO₂, acepromazine, midazolam, or saline. (B) *, Significant (P < 0.05) increase in dyspnea compared with that of respective preeuthanasia and induction scores (if applicable); α, indicates a significant increase in dyspnea compared with that for the respective preeuthanasia score.