口咽置入lidocaine，對降低麻醉時氣管插管循環反應的效果

Abstract

背景：研究顯示，口咽置入局部麻醉劑lidocaine，可降低光纖內視鏡清醒插管時的循環反應。本研究嘗試將此一局部麻醉效果，延伸用於麻醉誘導插管時。 目的：本研究在探討全身麻醉誘導期，插管前給予口咽置入局部麻醉劑2% lidocaine 5 ml，能否改善血壓和心率對氣管插管的反應。 材料和方法： 56位接受常規預定手術之成年病患被隨機分成二組，實驗組病患在全身麻醉誘導後45秒，於口咽置入局部麻醉劑2% lidocaine 5 mL，造成口咽及氣管表皮麻醉；對照組病患在全身麻醉誘導後45秒，於口咽置入生理鹽水5 mL。三分鐘後，給予受試者氣管插管，期間每分鐘監測受試者之血壓 (收縮壓、舒張壓、平均血壓) 和心率。口咽置入局部麻醉劑後，連續監測受試者每分鐘之血壓和心率達六分鐘。將兩組氣管插管後一分鐘之血壓和心率，以及其與基礎值之變動，以非配對 t-試驗比較，以確定口咽置入局部麻醉劑lidocaine，對降低氣管插管時循環反應的效果。 結果：在氣管插管後一分鐘之血壓和心率，lidocaine 組均比對照組為低(P < 0.05)。氣管插管後一分鐘之收縮壓、舒張壓、平均血壓與基礎值之變動差在對照組均較高 (P < 0.001)，然而心率變動差兩組並無差異。 結論：氣管插管前口咽置入局部麻醉劑lidocaine，可以降低因插管時刺激造成之心率及血壓的上升的循環反應。此為一簡單又有效，可以局部麻醉上呼吸道的方法，能使麻醉誘導及氣管插管時的循環反應較為平穩。

Purpose: This study attempts to determine whether oropharyngeal instillation of 5mL of 2% lidocaine for 3 min before intubation modifies changes in heart rate (HR) and blood pressure (BP) responses to the stimulation. Materials and methods: Fifty-six surgical patients were randomized to receive oropharyngeal instillation with either 5 mL of 2% lidocaine (lidocaine group) or 5 mL of normal saline (control group) 45 s after induction bolus. Systolic blood pressure (SBP), diastolic blood pressure (DBP), mean blood pressure (MBP), and HR were recorded every min thereafter for 6 min. Laryngoscopy and intubation was attempted at 3 min after intervention. The 1-min postintubation values of HR, SBP, DBP, and MBP between the groups, and their changes from baseline were compared as a priori using the unpaired t-test. Results: The 1-min postintubation values of SBP, DBP, MBP, and HR were significantly lower in the lidocaine group as compared to the control group (P < 0.05). The differences in mean values of SBP, DBP, and MBP changes from baseline were significantly greater in the control group (P ≤ 0.001), while that of HR was not significant. More patients (P < 0.001) become hypertensive at 1-min postintubation in the control group than in the lidocaine group. No differences in tachycardia incidence were found. Conclusion: We conclude that oropharyngeal administration of lidocaine before intubation attenuates the cardiovascular responses to the stimulation. It is a simple and effective method for achieving anesthesia of the upper airway and rendering induction smoother with respect to cardiovascular changes.