Comparison of the effect of sevoflurane and halothane anesthesia on the fall in heart rate as a predictor of successful single shot caudal epidural in children

OBJECTIVE: To investigate the effect of sevoflurane anesthesia on heart rate HR fall with the injection of the initial drug in caudal space to confirm the correct needle placement.

METHODS: After the ethical approval was obtained from the hospital's ethics committee, a prospective, randomized, clinical study was designed in Yeditepe University Hospital, in 2007. Children aged 1-12 years, scheduled for infraumblical surgery under general anesthesia, and caudal block were included in the study. Anesthesia was induced, and maintained by sevoflurane in group S n=85, and by halothane in group H n=82. Baseline HR was recorded before the caudal block was performed. The HR changes during the initial dose, and total drug injection were recorded followed by 2 more HR recordings taken 5, and 10 minutes after caudal injection. The success of the block was recorded by a blind observer.

RESULTS: There were 167 children included in the study. Caudal block success was 96.5% in group S, and 97.6% in group H. Basal HR was 110.9 ± 10.9 in group S, and 105.9 ± 10.1 in group H. Following the initial drug injection, mean HR was 109.8 ± 10.9 in group S, and 102.9 ± 9.9 in group H. It was significantly lower than the baseline in group H. The only significant decrease in the HR of the patients in group S was at the tenth minute following caudal injection.

CONCLUSION: The decrease in HR with drug injection has no value to predict the success of caudal block under sevoflurane anesthesia.