Otolaryngology Unit, Arcispedale Santa Maria Nuova-IRCCS, Reggio Emilia, Italy.
Am J Otolaryngol. 2014 Jan-Feb;35(1):62-5. doi: 10.1016/j.amjoto.2013.08.009. Epub 2013 Oct 10.
Lidocaine is commonly used for topical anesthesia of the upper airway in patient with anticipated difficult tracheal intubation undergoing awake fiberoptic intubation. Lidocaine toxicity is dose related and proportional to its plasma level. Although neurologic toxicity has been frequently observed with intravenous use, it has also been reported for topical use. We report on a case of a patient with base tongue abscess who developed sudden seizures and coma during application of topical anesthesia with lidocaine for awake fiberoptic intubation. The presence of a deep neck infection that causes hyperemia and edema of the pharyngolaryngeal mucosa may enhance transmucosal systemic absorption of local anesthetic. Moreover, conditions such as hypercarbia, dysphagia, or hepatic diseases are known to facilitate onset of lidocaine neurologic toxicity with serum concentration lower than normal. These findings should be kept in mind before administering topical anesthesia of the upper airway. In the presence of any of these conditions above, either the total dose of local anesthetic or its concentration should be reduced as much as possible.
利多卡因常用于预期行清醒纤维支气管镜插管的困难气管插管患者的上呼吸道表面麻醉。利多卡因的毒性与剂量有关，与其血浆水平成正比。虽然静脉内使用时经常观察到神经毒性，但也有报道用于局部使用。我们报告了一例基底舌脓肿患者，在清醒纤维支气管镜插管中使用利多卡因进行局部麻醉时突然发生癫痫发作和昏迷。深部颈部感染会导致咽喉黏膜充血和水肿，可能会增强局部麻醉药的经黏膜全身吸收。此外，高碳酸血症、吞咽困难或肝脏疾病等情况已知会降低血清浓度，从而更容易发生利多卡因神经毒性。在进行上呼吸道局部麻醉之前，应牢记这些发现。在存在上述任何一种情况时，应尽可能减少局部麻醉药的总剂量或其浓度。
