Table I.

MAC values and time for MAC determinations after administering ketamine (1 mg/kg BW bolus IV followed immediately by a CRI of 40 μg/kg BW per min) in 8 rabbits with same-day prior determination of baseline MAC of isoflurane (Group 1) or without same-day prior determination of baseline MAC of isoflurane (Group 2)

	Isoflurane baseline	Isoflurane + ketamine	After stopping ketamine	Total anesthesia time (min)
Group 1
MAC (%)	2.15 ± 0.09	1.63 ± 0.07*	2.04 ± 0.11†
Time (min)	80 ± 26	75 ± 16	80 ± 14	249 ± 15
Group 2
MAC (%)	ND	1.53 ± 0.22*	1.94 ± 0.25†
Time (min)	ND	103 ± 37	81 ± 20	205 ± 56

Values expressed as mean ± standard deviation (SD).

MAC — minimum alveolar concentration; BW — body weight; CRI — constant rate infusion; ND — not determined.

^*Significantly different within the group.

^†Significantly different (P < 0.05) from baseline isoflurane value.