用來減輕眼內壓上升而在插管前靜脈注射Lidocaine的最適當時間點

Lidocaine: The Optimal Timing of Intravenous Administration in Attenuation of Increase of Intraocular Pressure during Tracheal Intubation

背景：在插管的時候會增加眼內壓力。而眼內壓的上升對於一些病人，譬如，眼球有撕裂傷、眼球破裂、或最近有接受眼球手術的病人是有害的。而Lidocaine可用來減輕因插管造成的眼內壓上升。而本實驗之目的，在於找出用以減輕眼內壓，而在插管前經由靜脈給予Lidocaine 的最適當時間點。方法：我們收集了一百三十五位接受非眼科手術、ASAI、年紀20～35歲的病人，隨機將他們分成五組，在第II、III、IV、V組的病人分別在插管前1、3、5、10分鐘靜脈給予Lidocaine(2 mg/kg)。而第I組的病人則不給予Lidocaine，以做為控制組。結果：在第I、IV、V組的病人插管後眼內壓都明顯上升；反觀在第II、III組的病人在插管後，眼內壓比較沒有上升。另外，這五組的病人在插管後，血壓都明顯上升；而在第III組的病人血壓上升較少。在插管後一分鐘，第III、IV組病人的收縮血壓以及舒張血壓明顯低於控制組。結論：在年紀20到35歲健康的病人，接受手術時，在插管前一到三分鐘經由靜脈注射Lidocaine (2 mg/kg)，可以有效減輕眼內壓的上升。

Background: This study was designed to examine the optimal timing of intravenous lidocaine in attenuation of increase of intraocular pressure in response to laryngoscopy and tracheal intubation during induction of anesthesia. Methods: One hundred and thirty five adult patients of ASA class I, aged between 20-35 years, undergoing surgical procedures irrelevant to ophthalmology were enrolled for study. Patients were randomly assigned to one of five groups. In group II, III, IV and V the patients received intravenous injection of lidocaine (2 mg/kg), 1, 3, 5, 10 min before tracheal intubation, respectively. Group I in which patients did not receive lidocaine served as the control group. Results: In patients of groups I, IV and V, the intraocular pressure increased significantly after intubation, whereas in those of groups II and III, the intraocular pressure did not. All patients in the five groups showed concomitantly a surge of blood pressure, but the magnitude of increase was smallest in group III in comparison with the other groups. The values of systolic and diastolic pressures 1 min after intubation were significantly less in groups III and IV than in the control group. Conclusions: In healthy patients aged between 20 and 35 the most optimal time of administration of intravenous lidocaine to attenuate the increase of intraocular pressure seemed to be the space between 1 to 3 min before laryngoscopy and tracheal intubation.