Changes of Pressure in the Anal Canal during Caudal Epidural Anesthesia.

Abstract

Background:The purpose of this study was to measure the pressure in the anal canal during caudal epidural anesthesia. Methods:The pressure in the anal canal was measured via side-opening perfused catheter in 10 adult patients. The pressure under resting condition was recorded before and following the injection of 10 ml of 1.5% mepivacaine into the caudal epidural space. The pressure when anus was contracted at will was also meassured before and at 5min and 10min after injection. Results: After completion of the injection of mepivacaine, the pressure was gradually decreased. At 4min, the mean resting pressure was significantly decreased to 70% (p< 0.05). The voluntary contractive pressures at 5min and 10min were also significantly decreased to 65% and 51%, respectively (p<0.05). Conclusions:Decrease of pressure in the anal canal appeared surely and early. Pressure in the anal canal can be an effective indicator of the effect of caudal epidural anesthesia.

Predicting the success of caudal block

“…According to Takahashi et al. (5), caudal anesthesia changes anal canal pressures by relaxing the muscles in the anal area. They measured anal canal pressures for predicting the effectiveness of caudal and lumbar epidural anesthesia in adults.…”