Fig. 3

A higher dose of atipamezole and caffeine (see Fig. 2) accelerated emergence from dexmedetomidine sedation even more dramatically. Atipamezole by itself was not as effective as atipamezole with caffeine. The same group of 8 rats shown in Fig. 1 were exposed to 3 deep sedation sessions using bolus injections of dexmedetomidine (10 µg/kg), a week apart (protocol shown in supplementary material). At the end of each session the rats received a bolus injection of either saline or atipamezole (10 μg/kg) or atipamezole (10 μg/kg) with caffeine (25 mg/kg). The order of the drug injections was randomized. Rats were placed on their backs in a waking box, and the time for the rats to recover their righting reflex was recorded. This time is plotted in the figure as the emergence time. A, plots the time to emerge from sedation for rats receiving saline (leftmost group) or atipamezole (middle group) or atipamezole with caffeine (rightmost group). Using a repeated measures ANOVA (Tukey’s HSD Test for multiple comparisons) the mean value for emergence from sedation was significantly different for saline (control) vs atipamezole (p = 0.0003, 95% C.I. = [669 to 1485]); between saline (control) vs atipamezole with caffeine (p = 0.0002, 95% C.I. = [1096, 2381]); between atipamezole vs atipamezole with caffeine (p = 0.006, 95% C.I. = [245 to 1078]). B, Compares emergence times for 5 μg/kg atipamezole with caffeine with 10 μg/kg atipamezole with caffeine. The difference was significant (p = .002; paired T-test; n = 8). C, Compares emergence times for 5 μg/kg atipamezole with 10 μg/kg atipamezole. The difference was not significant (p = 0.62; paired T-test, n = 8). RORR Times (in seconds): Saline (control): 1938, 1532, 1490, 1273, 3121, 1700, 1985, 1325, Atipamezole (10 μg/kg): 750, 1145, 513, 210, 1311, 719, 760, 338, Atipamezole (10 μg/kg) with Caffeine (25 mg/kg): 15, 24, 241, 18, 32, 52, 20, 55