We compared, in this prospective, randomized, double-blinded study, the characteristics of spinal anesthesia with plain and hyperbaric ropivacaine for elective cesarean delivery. We hypothesized that the addition of glucose would change the onset, offset, and extent of motor and sensory block from intrathecal ropivacaine. Forty ASA physical status I–II women were given 25 mg of either ropivacaine (n = 20) or ropivacaine in 8.3% glucose (n = 20) intrathecally, via a combined spinal/epidural technique in the right lateral position. Sensory changes to ice and pinprick and motor block (Bromage score) were recorded at 2.5-min intervals. Adequate anesthesia for surgery was achieved in all patients in the Hyperbaric group, whereas in the Plain group, five (25%) patients required epidural top-up because of insufficient rostral spread (P < 0.05). With hyperbaric ropivacaine, we found the following: higher cephalic spread (median [range] maximum block height to pinprick, T1 [T4 to C2] versus T3 [T11 to C3], P < 0.001); lower coefficient of variation of maximum block height (17.7% vs 21.9%); faster onset to T4 dermatome (mean [sd] 7.7 [4.9] vs 16.4 [14.1] min, P = 0.015); and faster recovery to L1 (189.0 [29.6] vs 215.5 [27.0] min, P = 0.01). The onset of complete motor block (9.9 [5.3] vs 13.8 [5.4] min, P = 0.027) and complete recovery (144.8 [28.4] vs 218.5 [56.8] min, P < 0.001) was also faster. No neurologic symptoms were found at 24 h.
Department of Anaesthesia and Intensive Care, The Chinese University of Hong Kong, Shatin, Hong Kong, China
Internally funded by the Department of Anaesthesia and Intensive Care, The Chinese University of Hong Kong.
Presented in part at the International Anesthesia Research Society 75th Clinical and Scientific Congress, Fort Lauderdale, FL, March 16–20, 2001.
October 23, 2001.
Address correspondence and reprint requests to Kim S. Khaw, FRCA, Department of Anaesthesia and Intensive Care, The Chinese University of Hong Kong, Prince of Wales Hospital, Shatin, Hong Kong SAR, China. Address e-mail to KimKhaw@cuhk.edu.hk.