F Xu1, M Qian1, Y Wei2, Y Wang2, J Wang1, M Li1, Y Zhang2, Y Zhao2, X Guo3. 1. Department of Anesthesiology, Peking University Third Hospital, Beijing, China. 2. Department of Obstetrics and Gynecology, Peking University Third Hospital, Beijing, China. 3. Department of Anesthesiology, Peking University Third Hospital, Beijing, China. Electronic address: xiangyangguoby@163.com.
Abstract
BACKGROUND:Spinal anesthesia is widely used for cesarean section, but the factors that affect the spread of the block in pregnant patients are still not fully explained. This study was designed to investigate the effect of postural changes on sensory block level. METHODS:Thirty patients scheduled for elective cesarean section under combined spinal-epidural anesthesia were randomly allocated into three groups. After intrathecal injection of 0.5% plain bupivacaine 7.5mg, patients in group S were immediately placed in the supine position with left tilt, patients in group L5 were kept lateral for 5 min and then turned to the supine position with left tilt, and patients in group L10 were kept lateral for 10 min and then turned to the supine position with left tilt. RESULTS: At 5 min, median cephalad level of sensory block was lower in groups L5 and L10 compared with group S (corrected P<0.001); at 10 min, median cephalad sensory block level was lower in group L10 compared with group S (corrected P<0.001) and group L5 (corrected P<0.001), and lower in group L5 compared with group S (corrected P=0.033); at 15 min, median cephalad level of sensory block was lower in group L10 compared with group S (corrected P=0.003) and group L5 (corrected P=0.015). CONCLUSIONS: In our population, using 0.5% plain bupivacaine 7.5mg, postural change from the lateral position to the supine position is an important mechanism enhancing cephalic spread of spinal anesthesia during late pregnancy.
RCT Entities:
BACKGROUND: Spinal anesthesia is widely used for cesarean section, but the factors that affect the spread of the block in pregnant patients are still not fully explained. This study was designed to investigate the effect of postural changes on sensory block level. METHODS: Thirty patients scheduled for elective cesarean section under combined spinal-epidural anesthesia were randomly allocated into three groups. After intrathecal injection of 0.5% plain bupivacaine 7.5mg, patients in group S were immediately placed in the supine position with left tilt, patients in group L5 were kept lateral for 5 min and then turned to the supine position with left tilt, and patients in group L10 were kept lateral for 10 min and then turned to the supine position with left tilt. RESULTS: At 5 min, median cephalad level of sensory block was lower in groups L5 and L10 compared with group S (corrected P<0.001); at 10 min, median cephalad sensory block level was lower in group L10 compared with group S (corrected P<0.001) and group L5 (corrected P<0.001), and lower in group L5 compared with group S (corrected P=0.033); at 15 min, median cephalad level of sensory block was lower in group L10 compared with group S (corrected P=0.003) and group L5 (corrected P=0.015). CONCLUSIONS: In our population, using 0.5% plain bupivacaine 7.5mg, postural change from the lateral position to the supine position is an important mechanism enhancing cephalic spread of spinal anesthesia during late pregnancy.