Craig S B, Concannon M J, McDonald G A, Puckett C L
Division of Plastic Surgery, University of Missouri, Columbia 65212, USA.
Plast Reconstr Surg. 1999 Feb;103(2):666-70. doi: 10.1097/00006534-199902000-00047.
Tumescent liposuction is currently one of the most commonly performed aesthetic procedures. Despite the variable use of preoperative antibiotics, infection is uncommon. Prior works suggest that the low incidence of infection may be due to lidocaine's antibacterial properties. However, these properties have only been demonstrated using concentrations of lidocaine above 0.8%, significantly higher than those used in tumescent liposuction. The purpose of this study was to determine if the commonly used tumescent fluid containing 0.1% lidocaine, 1:1000,000 epinephrine, and 0.012 mEq sodium bicarbonate possesses antibacterial activity. Using the broth microdilution method, the minimum inhibitory concentrations of Escherichia coli, Proteus mirabilis, Pseudomonas aeruginosa, Staphylococcus aureus, and Group A beta-hemolytic Streptococcus were determined after exposure to either lidocaine, epinephrine, bicarbonate, or the combination of all three agents. To determine if there were significant growth differences not detectable by the broth microdilution method, bacterial concentrations were obtained through the use of a spectrophotometer, and significant differences from the controls were calculated by one-way analysis of variance. To determine if prolonged exposure to the tumescent mix would alter bacterial growth, a Killing Time study was also undertaken. The results indicated that the minimum inhibitory concentration of lidocaine was not less than 0.5% for any of the bacteria, whereas the lowest minimum inhibitory concentration of the combined solution was 0.25%. The lowest inhibitory concentration as determined by spectrophotometric analysis for the combined solution was 0.13% (p < 0.01). Analysis of the Killing Time data revealed no inhibition of bacterial growth over time. In conclusion, lidocaine, epinephrine, and bicarbonate do exhibit antibacterial properties at high concentrations. However, the commonly used tumescent mixture containing dilute concentrations of these agents does not significantly inhibit the growth of commonly encountered bacteria.
肿胀吸脂术是目前最常施行的美容手术之一。尽管术前抗生素的使用情况各不相同，但感染并不常见。先前的研究表明，感染发生率低可能是由于利多卡因的抗菌特性。然而，这些特性仅在利多卡因浓度高于0.8%时得到证实，远高于肿胀吸脂术中使用的浓度。本研究的目的是确定常用的含有0.1%利多卡因、1:1000000肾上腺素和0.012 mEq碳酸氢钠的肿胀液是否具有抗菌活性。采用肉汤微量稀释法，测定大肠杆菌、奇异变形杆菌、铜绿假单胞菌、金黄色葡萄球菌和A组β溶血性链球菌在暴露于利多卡因、肾上腺素、碳酸氢盐或这三种药物组合后的最低抑菌浓度。为了确定肉汤微量稀释法无法检测到的显著生长差异，通过使用分光光度计获得细菌浓度，并通过单因素方差分析计算与对照组的显著差异。为了确定长时间暴露于肿胀混合液是否会改变细菌生长，还进行了杀菌时间研究。结果表明，任何一种细菌的利多卡因最低抑菌浓度均不低于0.5%，而混合溶液的最低最低抑菌浓度为0.25%。分光光度分析确定的混合溶液最低抑菌浓度为0.13%（p < 0.01）。杀菌时间数据分析显示，随着时间的推移，细菌生长没有受到抑制。总之，利多卡因、肾上腺素和碳酸氢盐在高浓度时确实具有抗菌特性。然而，含有这些药物稀释浓度的常用肿胀混合液并不能显著抑制常见细菌的生长。
