Sakuragi T, Ishino H, Dan K
Department of Anesthesiology, School of Medicine, Fukuoka University, Japan.
Acta Anaesthesiol Scand. 1998 Oct;42(9):1096-9. doi: 10.1111/j.1399-6576.1998.tb05383.x.
The rate at which the bactericidal activity of preservative-free bupivacaine develops at body temperature and at room temperature is not known. We studied the bactericidal activity of preservative-free bupivacaine on two strains of methicillin-resistant Staphylococcus aureus (MRSA), two strains of methicillin-susceptible S. aureus (MSSA), and each of Staphylococcus epidermidis and Escherichia coli.
The pathogen was exposed to 0.5% bupivacaine for 1, 3, 6, 12, and 24 h at 37 degrees C and room temperature. In addition, each strain of MRSA, MSSA, and S. epidermidis was exposed to distilled water, and 0.125%, 0.25%, 0.5%, and 0.75% bupivacaine at 37 degrees C. The inocula from the suspensions were cultured for 48 h at 37 degrees C.
The 1- through 24-h exposures of 4 strains of S. aureus to 0.5% bupivacaine at room temperature reduced the colony count by 21.7%, 34.7%, 51.1%, 65.6%, and 81.1%, respectively, and the exposure at 37 degrees C reduced the count by 34.1%, 50.8%, 66.3%, 94.5%, and 96.0%, respectively. The differences were significant at all exposure times (P < 0.001, respectively). No organisms grew in the strain of E. coli after 24-h exposure and in the strain of S. epidermidis after 12- and 24-h exposures at 37 degrees C. The percent change from controls in the strains of E. coli and S. epidermidis was significantly higher than that in the strains of S. aureus at all exposure times at room temperature and 37 degrees C (P < 0.0001, respectively). Higher concentrations of bupivacaine were associated with lower colony count.
Our results show that preservative-free bupivacaine possesses a temperature- and concentration-dependent bactericidal activity, and S. aureus is more resistant to the bactericidal activity of bupivacaine than are S. epidermidis and E. coli.
不含防腐剂的布比卡因在体温和室温下的杀菌活性发展速率尚不清楚。我们研究了不含防腐剂的布比卡因对两株耐甲氧西林金黄色葡萄球菌（MRSA）、两株甲氧西林敏感金黄色葡萄球菌（MSSA）、表皮葡萄球菌和大肠杆菌的杀菌活性。
将病原体在37℃和室温下暴露于0.5%布比卡因中1、3、6、12和24小时。此外，将每株MRSA、MSSA和表皮葡萄球菌暴露于蒸馏水中，以及在37℃下暴露于0.125%、0.25%、0.5%和0.75%布比卡因中。将悬浮液的接种物在37℃下培养48小时。
4株金黄色葡萄球菌在室温下暴露于0.5%布比卡因1至24小时，菌落数分别减少21.7%、34.7%、51.1%、65.6%和81.1%，在37℃下暴露，菌落数分别减少34.1%、50.8%、66.3%、94.5%和96.0%。在所有暴露时间差异均有统计学意义（P均<0.001）。在37℃下，大肠杆菌菌株暴露24小时后以及表皮葡萄球菌菌株暴露12和24小时后均无细菌生长。在室温下和37℃下的所有暴露时间，大肠杆菌和表皮葡萄球菌菌株相对于对照的变化百分比均显著高于金黄色葡萄球菌菌株（P均<0.0001）。布比卡因浓度越高，菌落数越低。
我们的结果表明，不含防腐剂的布比卡因具有温度和浓度依赖性杀菌活性，并且金黄色葡萄球菌比表皮葡萄球菌和大肠杆菌对布比卡因的杀菌活性更具抗性。
