靜脈注射Lidocaine對於全身麻醉中氣管插管時之心率變異趨勢並無影響

Lack of Intravenous Lidocaine Effects on HRV Changes of Tracheal Intubation during Induction of General Anesthesia

背景：Lidocaine靜脈注射有時在全身麻醉誘導期被用於抑制氣管插管之自主神經反應。以前相關的研究多只測量心跳血壓的變化，因而對其效果如何，無法得到一致的結論。心率變異是一種測量自主神經調節的非侵入性方法，適合用來進行上述之研究。方法：36名ASA Class I-II，接受全身麻醉之病患，予以分成三組。除了一般的麻醉誘導劑之外，在A組於氣管插管前5分鐘給予靜脈lidocaine 1.5 mg/kg，B組於插管前3分鐘給此lidocaine，而C組則不給lidocaine。於清醒、插管前及插管後三段時間以時頻域分析法計算心率變異頻譜之高頻、中頻能量及二者之比值並在三組之間加以比較。結果：心率變異頻率之高頻、中頻能量及其比值，在三個觀察時段在三組之間皆無統計上顯著之差異。結論：在全身麻醉誘導劑之作用下，由本實驗之結果無法支持靜注lidocaine在氣管插管時對自主神經反應之抑制效果。

Background: Intravenous lidocaine has been widely used for suppressing the autonomic activation from tracheal intubation during induction of general anesthesia. Conventionally, researches of its effectiveness through assessment of heart rate and blood pressure changes obtained by common clinical methods result in the conclusions deduced of much controversy. Heart rate variability is a noninvasive measurement of autonomic regulation and is suitable for the study of this subject. Methods: 36 ASA class I-II patients undergoing general anesthesia were divided into 3 groups. Besides induction agents, intravenous lidocaine was given 5 min before tracheal intubation in group A, 3 min before intubation in group B and nothing in group C. HRV spectral powers were measured at awake state, anesthetized state before tracheal intubation and anesthetized state after tracheal intubation by time frequency spectral analysis method and comparison was made between the three groups. Results: The HRV spectral power in high frequency (HF) and mid-frequency (MF) power bands and their ratios (MF/HF) were not significantly different among the 3 groups during the 3 observation periods. Conclusions: There was no evidence to indicate the effectiveness of intravenous lidocaine on the autonomic regulation during tracheal intubation under the influence of induction agents used in general anesthesia.