Todd K, Berk W A, Huang R
Department of Emergency Medicine, Detroit Receiving Hospital, Michigan.
Ann Emerg Med. 1992 Jun;21(6):723-6. doi: 10.1016/s0196-0644(05)82787-8.
Little information exists relating body locale to the duration of action of local anesthetics. We tested the duration of action of a local anesthetic with and without epinephrine at different body locales.
Twenty healthy volunteers aged 27 to 48 years (mean, 32.0 years).
In the first of two experiments (L), 20 subjects had 1 mL buffered 1% lidocaine injected intradermally on the forehead, hand, forearm, and calf. In the second experiment (LE), ten subjects were injected at the same sites with lidocaine containing epinephrine.
Subjects ranked anesthesia by reaction to pinprick from 0 (complete) to 20 (none) on a scale with testing done every 15 (L) or 30 (LE) minutes and continued until no anesthetic effect was present. Duration of effective and of any anesthesia were times until score of more than 5 and of more than 19, respectively. Mean duration of anesthesia was compared by analysis of variance (between body areas) and paired two-tailed t-test (L vs LE). Significance was taken as P less than or equal to .05.
Anesthesia was significantly briefer for the face than for all other body locales by both indexes of duration and for both plain lidocaine and lidocaine with epinephrine (P less than .001 to P less than .05). Anesthesia with epinephrine lasted significantly longer than with lidocaine alone at all body locales and for duration of both effective or any anesthesia (P = .0001 to P = .001). Based on 95% confidence interval limits, the duration of anesthesia at other body locales is predicted to be 1.3- to 3.2-fold that on the face. Confidence interval analysis indicated that addition of epinephrine to lidocaine increases the duration of anesthetic action by 1.3- to 13.0-fold that of lidocaine alone.
The duration of action of local anesthesia is considerably shorter for the face than for other body areas. Epinephrine significantly increases the duration of action of lidocaine at all body locales.
关于局部麻醉药作用持续时间与身体部位之间的关系，现有信息较少。我们测试了在不同身体部位使用含肾上腺素和不含肾上腺素的局部麻醉药的作用持续时间。
20名年龄在27至48岁之间（平均32.0岁）的健康志愿者。
在两项实验中的第一项实验（L）中，20名受试者在前额、手部、前臂和小腿进行皮内注射1毫升缓冲的1%利多卡因。在第二项实验（LE）中，10名受试者在相同部位注射含肾上腺素的利多卡因。
受试者根据对针刺的反应将麻醉程度从0（完全麻醉）到20（无麻醉）进行评分，实验（L）每15分钟进行一次测试，实验（LE）每30分钟进行一次测试，持续进行直到不再有麻醉效果。有效麻醉持续时间和任何麻醉持续时间分别是直到评分超过5和超过19的时间。通过方差分析（身体部位之间）和配对双尾t检验（L与LE）比较平均麻醉持续时间。显著性水平设定为P小于或等于0.05。
无论是根据持续时间指标，还是对于普通利多卡因和含肾上腺素的利多卡因，面部麻醉的持续时间均显著短于所有其他身体部位（P小于0.001至P小于0.05）。在所有身体部位，含肾上腺素麻醉的持续时间在有效麻醉或任何麻醉持续时间方面均显著长于单独使用利多卡因（P = 0.0001至P = 0.001）。根据95%置信区间范围预测，其他身体部位的麻醉持续时间是面部的1.3至3.2倍。置信区间分析表明，向利多卡因中添加肾上腺素可使麻醉作用持续时间比单独使用利多卡因增加1.3至13.0倍。
面部局部麻醉的作用持续时间比其他身体部位短得多。肾上腺素在所有身体部位均显著增加利多卡因的作用持续时间。
