Tsutsui Yukako, Sunada Katsuhisa
Department of Dental Anesthesiology, The Nippon Dental University School of Life Dentistry at Tokyo, Tokyo, Japan.
Anesth Prog. 2020 Jun 1;67(2):72-78. doi: 10.2344/anpr-66-04-06.
Articaine is a low-toxicity local anesthetic that is widely used in dentistry. Typically, epinephrine is added to prolong the duration of articaine local anesthesia; however, epinephrine exhibits adverse effects. Low-dose dexmedetomidine (DEX), an α2-adrenoreceptor agonist, reportedly prolongs local anesthesia without notable adverse cardiovascular effects. The purpose of this study was to assess whether a combination of low-dose DEX and articaine would provide a low-toxicity local anesthetic option for dental procedures without adverse cardiovascular effects. Thus, this study investigated whether DEX could prolong the local anesthetic effect of articaine using a rat model of pain. Adult male Wistar rats (N = 44; 11 per group) received a 50-μL subcutaneous injection into the plantar surface of the hind paws; injections were composed of either normal saline, 4% articaine (2 mg articaine), combined 5 μg/kg DEX and 4% articaine (1.25 μg DEX + 2 mg articaine), or combined epinephrine (1:100,000) and 4% articaine (0.9 μg epinephrine + 2 mg articaine). Subsequent acute pain perception was determined by paw withdrawal movement in response to infrared radiant heat stimulation of the plantar region. Paw withdrawal latency was tested at 5-minute intervals. Paw withdrawal latency values at 35 and 40 minutes were 3.83 ± 1.76 and 3.29 ± 1.43 seconds for articaine alone, 7.89 ± 2.72 and 7.25 ± 3.37 seconds for DEX and articaine, and 8.95 ± 2.28 and 8.17 ± 3.01 seconds for epinephrine and articaine. DEX prolonged the paw withdrawal latency of articaine for up to 35 minutes (p = .015) but not 40 minutes after injection (p = .052) when compared to articaine alone. The combination of DEX and articaine can provide effective local anesthesia for up to 35 minutes after injection.
阿替卡因是一种低毒的局部麻醉剂，广泛应用于牙科领域。通常，会添加肾上腺素以延长阿替卡因局部麻醉的持续时间；然而，肾上腺素会产生不良反应。低剂量右美托咪定（DEX）是一种α2肾上腺素能受体激动剂，据报道它能延长局部麻醉时间，且无明显的心血管不良反应。本研究的目的是评估低剂量DEX与阿替卡因联合使用是否能为牙科手术提供一种低毒的局部麻醉选择，且无心血管不良反应。因此，本研究使用大鼠疼痛模型研究了DEX是否能延长阿替卡因的局部麻醉效果。成年雄性Wistar大鼠（N = 44；每组11只）在后爪足底表面接受50μL皮下注射；注射剂分别为生理盐水、4%阿替卡因（2mg阿替卡因）、5μg/kg DEX与4%阿替卡因联合制剂（1.25μg DEX + 2mg阿替卡因）或肾上腺素（1:100,000）与4%阿替卡因联合制剂（0.9μg肾上腺素 + 2mg阿替卡因）。随后通过对足底区域进行红外辐射热刺激时的爪退缩运动来确定急性疼痛感知。每隔5分钟测试一次爪退缩潜伏期。单独使用阿替卡因时，35分钟和40分钟时的爪退缩潜伏期值分别为3.83±1.76秒和3.29±1.43秒；DEX与阿替卡因联合使用时，分别为7.89±2.72秒和7.25±3.37秒；肾上腺素与阿替卡因联合使用时，分别为8.95±2.28秒和8.17±3.01秒。与单独使用阿替卡因相比，DEX可将阿替卡因的爪退缩潜伏期延长至35分钟（p = 0.015），但注射后40分钟时无延长效果（p = 0.052）。DEX与阿替卡因联合使用可在注射后长达35分钟内提供有效的局部麻醉。
