Christoph R A, Buchanan L, Begalla K, Schwartz S
University of Virginia Medical Center, Emergency Medical Services, Charlottesville 22908.
Ann Emerg Med. 1988 Feb;17(2):117-20. doi: 10.1016/s0196-0644(88)80293-2.
The effects of pH buffering on the pain of administration and efficacy of three local anesthetics (1% lidocaine, 1% lidocaine with 1:100,000 epinephrine, and 1% mepivacaine) were investigated in a randomized, prospective, double-blind study of 25 adult volunteers. Plain and buffered solutions of the three local anesthetics were prepared, and a 0.5 intradermal injection of each was administered. Pain of anesthetic infiltration was rated from zero to ten. The area of anesthetized skin surrounding each injection site was measured at time intervals following each injection. Buffering the local anesthetics significantly reduced the mean quantitative pain estimates compared to the nonbuffered controls: 1) 1% lidocaine compared with buffered 1% lidocaine, 4.9 +/- 0.4 versus 1.1 +/- 0.2 (P less than 10(-6)); 2) 1% lidocaine with epinephrine compared with buffered 1% lidocaine with epinephrine, 5.1 +/- 0.4 versus 1.8 +/- 0.4 (P less than 10(-6)); and 3) 1% mepivacaine compared with buffered 1% mepivacaine, 5.1 +/- 0.4 versus 0.9 +/- 0.2 (P less than 10(-6)). Onset, extent, and duration of skin anesthesia were not statistically altered by pH buffering. The pain of local anesthetic administration can be dramatically reduced by buffering the local anesthetic prior to its infiltration. Anesthetic efficacy is not compromised, and patient acceptance may be significantly increased.
在一项针对25名成年志愿者的随机、前瞻性、双盲研究中，研究了pH缓冲对三种局部麻醉剂（1%利多卡因、含1:100,000肾上腺素的1%利多卡因和1%甲哌卡因）给药疼痛及疗效的影响。制备了三种局部麻醉剂的普通溶液和缓冲溶液，并分别进行0.5ml皮内注射。将麻醉剂浸润的疼痛程度从零到十分进行评分。在每次注射后的不同时间间隔测量每个注射部位周围麻醉皮肤的面积。与未缓冲的对照组相比，缓冲局部麻醉剂显著降低了平均定量疼痛估计值：1）1%利多卡因与缓冲后的1%利多卡因相比，分别为4.9±0.4和1.1±0.2（P＜10⁻⁶）；2）含肾上腺素的1%利多卡因与缓冲后的含肾上腺素的1%利多卡因相比，分别为5.1±0.4和1.8±0.4（P＜10⁻⁶）；3）1%甲哌卡因与缓冲后的1%甲哌卡因相比，分别为5.1±0.4和0.9±0.2（P＜10⁻⁶）。pH缓冲对皮肤麻醉的起效、范围和持续时间无统计学改变。在局部麻醉剂浸润前进行缓冲可显著减轻局部麻醉剂给药时的疼痛。麻醉效果不受影响，患者接受度可能会显著提高。
