The effect of caffeine on recovery time and brain waves in emergence from sevoflurane anesthesia in rats

Aim: We aimed to investigate how caffeine, which inhibits the destruction of cAMP by phosphodiesterase inhibition, affects recovery from sevoflurane anesthesia and brain wave activity. Materials and Methods: Electrodes were attached to 16 Sprague-Dawley male rat skulls for ECoG recording after anesthetisia with ketamine/xylazine. The rats were randomly divided into 2 groups as control and caffeine (75 mg/kg) after 1 week. The rats were sequentially placed in a gas-tight anesthesia box and sevoflurane anesthesia was applied for 60 minutes after five minutes of basal EEG recording. At the 50th minute of anesthesia, 2ml/kg SF was injected intraperitoneally to the rats in the control group and 75 mg/kg caffeine was injected intraperitoneally to the rats in the study group. The respiratory frequencies of the rats were recorded before the experiment, during anesthesia and after anesthesia. Then, the sevoflurane anesthesia was discontinued. The time during which the tail clamp and righting (full recovery) reflexes came back was noted. ECoG recordings were recorded and after the experiment, statistical analysis was performed by calculating the delta + theta wave frequency and wave amplitudes. Results: Caffeine administration decreased the tail clamp reflex and righting reflex recovery time compared to the control group (p=0.042; p=0.003, respectively). The number of breaths increased at the 5th and 10th minutes after caffeine injection compared to the control group (p<0.001; p<0.001, respectively). Caffeine injection significantly decreased theta+delta wave number between the 4th and 10th minutes compared to the control group (p<0.05). Compared to the average amplitudes after injections, caffeine injection reduced the theta + delta waves total amplitude average (p=0.008). Conclusion: We found that caffeine administered intraperitoneally to rats under sevoflurane anesthesia reduced brain delta + theta wave numbers and total average wave amplitudes and shortened the recovery time from anesthesia. Keywords: Caffeine, Sevoflurane, Recovery Time, EEG