Syverud S A, Jenkins J M, Schwab R A, Lynch M T, Knoop K, Trott A
University of Virginia Health Sciences Center, Emergency Medical Services University Hospitals, Charlottesville 22908, USA.
Acad Emerg Med. 1994 Nov-Dec;1(6):509-13. doi: 10.1111/j.1553-2712.1994.tb02542.x.
Mental nerve block is frequently used to aid repair of facial lacerations; both percutaneous and intraoral approaches to blocking this nerve are used, but have never been compared. The authors compared the two techniques for pain of administration and effectiveness of anesthesia.
A prospective, randomized, single-blind, crossover study was conducted using ten healthy volunteers aged 22 to 33 years. Patients having prior experience with mental nerve blocks, lidocaine allergy, active oral/facial infection, or previous facial fractures were excluded. Bilateral mental nerve blocks were done using intraoral technique on one side and percutaneous technique on the other. Both techniques were used by the same investigator and were carried out with 27-gauge needles and 2.5 mL of 2% buffered lidocaine at room temperature injected over 20 seconds. The oral mucosa was topically anesthetized with viscous lidocaine for 1 minute prior to intraoral injection. The orders of the blocks and sides of the face anesthetized were randomized. Subjective and objective pain (visual-analog scale), efficacy (anesthesia of lower lip), time to onset, and duration of anesthesia were evaluated.
The intraoral technique was subjectively less painful than the percutaneous approach in nine of ten subjects (p = 0.02). Scores on the visual-analog pain scale were significantly lower for the intraoral technique (p = 0.03). Intraoral injection produced lower-lip anesthesia in 10/10 subjects versus 7/10 for percutaneous (p = 0.25). Times to onset (approximately 1-2 minutes) and durations of anesthesia (approximately one hour) were similar for the two techniques.
The intraoral approach to the mental nerve block with adjunctive topical anesthesia was subjectively and objectively less painful than the percutaneous approach without adjunctive anesthesia. While the intraoral approach had a greater efficacy of lower-lip anesthesia and a longer duration of action, these differences were not statistically significant.
颏神经阻滞常用于辅助面部裂伤修复；阻滞该神经的经皮和口内途径均有使用，但从未进行过比较。作者比较了这两种技术在给药疼痛和麻醉效果方面的差异。
采用前瞻性、随机、单盲、交叉研究，纳入10名年龄在22至33岁之间的健康志愿者。排除既往有颏神经阻滞经验、利多卡因过敏、口腔/面部活动性感染或既往有面部骨折的患者。一侧采用口内技术进行双侧颏神经阻滞，另一侧采用经皮技术。两种技术均由同一名研究者操作，使用27号针头和2.5 mL室温下的2%缓冲利多卡因，在20秒内注射完毕。在口内注射前，用粘性利多卡因对口腔黏膜进行局部麻醉1分钟。阻滞顺序和麻醉的面部侧别均随机安排。评估主观和客观疼痛（视觉模拟评分）、疗效（下唇麻醉情况）、起效时间和麻醉持续时间。
10名受试者中有9名认为口内技术在主观上比经皮途径疼痛轻（p = 0.02）。口内技术的视觉模拟疼痛评分显著更低（p = 0.03）。口内注射使10/10的受试者出现下唇麻醉，而经皮注射为7/10（p = 0.25）。两种技术的起效时间（约1 - 2分钟）和麻醉持续时间（约1小时）相似。
在辅助局部麻醉的情况下，口内途径进行颏神经阻滞在主观和客观上都比无辅助麻醉的经皮途径疼痛轻。虽然口内途径在下唇麻醉方面有更高的疗效和更长的作用持续时间，但这些差异无统计学意义。
