Heard A M B, Green R J, Lacquiere D A, Sillifant P
Royal Perth Hospital, Perth, Australia.
Anaesthesia. 2009 Nov;64(11):1196-8. doi: 10.1111/j.1365-2044.2009.06066.x.
Acute trismus can be caused by pain, muscle spasm, swelling or mechanical obstruction. Unfortunately, the cause is not always obvious during pre-operative airway assessment. In this pilot study, we prospectively evaluated mandibular nerve block as a pre-operative tool to identify patients with reversible causes of trismus, namely pain or spasm, in order to allow safe anaesthetic induction. Six patients with unilateral fractured mandibles and trismus received a mandibular nerve block before induction of general anaesthesia. There was an increase in maximal inter-incisor gap after the blocks (median (range) distance: pre-block 16.5 (14-30) and post-block 34 (32-35) mm; p = 0.027), and no further improvement after induction of general anaesthesia (post-induction 37 (30-40) mm; p = 0.276 compared with post-block). There was an improvement in pain scores (p = 0.027), and no side-effects were detected. Pre-operative mandibular nerve blockade appears to reverse trismus caused by pain and muscle spasm, allowing the anaesthetist to decide whether awake intubation is genuinely indicated.
急性牙关紧闭可由疼痛、肌肉痉挛、肿胀或机械性梗阻引起。不幸的是，在术前气道评估期间，病因并不总是显而易见。在这项前瞻性试点研究中，我们评估了下颌神经阻滞作为一种术前工具，以识别牙关紧闭可逆性病因（即疼痛或痉挛）的患者，从而实现安全的麻醉诱导。6例单侧下颌骨骨折伴牙关紧闭的患者在全身麻醉诱导前接受了下颌神经阻滞。阻滞术后最大切牙间隙增加（中位数（范围）距离：阻滞前16.5（14 - 30）mm，阻滞后34（32 - 35）mm；p = 0.027），全身麻醉诱导后无进一步改善（诱导后37（30 - 40）mm；与阻滞术后相比，p = 0.276）。疼痛评分有所改善（p = 0.027），且未检测到副作用。术前下颌神经阻滞似乎可逆转由疼痛和肌肉痉挛引起的牙关紧闭，使麻醉医生能够决定是否真的需要清醒插管。
