在Etomidate誘導下，藉使用 Fentanyl或Succinylcholine改善喉頭罩呼吸道置放的成功率

Improving the Success Rate of Laryngeal Mask Airway Insertion during Etomidate Induction by Using Fentanyl or Succinylcholine

背景：在以etomidate誘導下，要平順並成功的置放喉頭罩呼吸道(LMA)需要適度的張口動作及減低呼吸道反射，如作嘔、咳嗽、或喉頭痙攣。我們假設，在使用etomidate為麻醉誘導藥物時，併用fentanyl或succinylcholine可以減少呼吸道反射的發生率，及增加喉頭罩呼吸道置放的成功率。方法：共60位排定接受全身麻醉手術，ASA I-II的成年患者隨機分為3組：(1) etomidate 0.3 mg/ kg (2) fentanyl 2 μg/kg，及etomidate 0.3 mg/kg (3) etomidate 0.3 mg/kg，及succinylcholine 1 mg/kg。在麻醉前給藥atropine 0.01 mg/kg後，紀錄由開始給予fentanyl或麻醉誘導藥物後，到所需之下顎放鬆的時間，並檢視患者在給藥後是否有躁動動作。在喉頭罩置入後，檢視有無呼吸道反射的徵象。我們使用Student's t test及Chi-square test來分析資料。以P< 0.05為有顯著意義。結果：這3組中，病患的基本資料並無顯著差異。在以etomidate誘導併用fentanyl或succinylcholine下，可以比單純用etomidate誘導明顯減少喉頭罩置放後的躁動動作和呼吸道反射，並增加喉頭罩置放的成功率。在這2種輔助藥物中，併用succinylcholine可以比併用fentanyl提供明顯較佳的下顎放鬆效果，縮短置入喉頭罩呼吸道的時間，及增加喉頭罩放置的成功率。結論：在LMA置放時的麻醉誘導藥物上，單純用etomidate並非理想選擇。併用fentanyl 2 μg/kg可明顯減少喉頭罩置入後的呼吸道反射，並增加置放成功率。然而，併用succinylcholine 1 mg/kg可提供縮短置入喉頭罩的時間，下顎鬆弛，及喉頭罩置放成功率等方面更好的結果。

Background: Smooth and successful insertion of a laryngeal mask airway (LMA) during etomidate induction requires a proper mouth opening and efforts to minimize airway reflexes such as gagging, coughing, or laryngospasm. We hypothesized that the concurrent use of fentanyl or succinylcholine with etomidate, the induction agent, could reduce the occurrence of airway reflexes and increase the success rate of LMA. Methods: Sixty adult patients, ASA class I-II, scheduled for surgery under general anesthesia, were randomly allocated into three groups: group I in which patients were given etomidate 0.3 mg/kg alone; group 2 in which patients were given fentanyl 2 μg/kg and etomidate 0.3 mg/kg; groups 3 in which patients were give etomidate 0.3 mg/kg and succinylcholine 1 mg/kg. All patients were premedicated with atropine 0.01 mg/kg. When induction of anesthesia began we recorded the time from administering the designated regiminal agent or agents to the time of relaxation of jaw (the ease of mouth opening) and checked the patient for any excitatory movement after administering the induction agents. After inserting the LMA, we checked for signs of airway reflexes. Student's t test, Chi-square and Fisher's exact test were used to analyze the data. A value of P < 0.05 was considered significant. Results: There were no significant differences in demographic data among the the three groups. The concurrent use of fentanyl or succinylcholine with etomidate during induction could significantly reduce the occurrence of excitatory movements and airway reflexes after LMA insertion, and increase the success rate of LMA insertion in comparison with using etomidate alone. Comparing the two adjutant agents, the concurrent use of succinylcholine could provide a significantly better jaw relaxation, shorten the time to insert the LMA and increase the success rate of LMA insertion. Conclusions: As an induction agent to facilitate insertion of LMA, etomidate alone was far from perfect. The concurrent use of 2 μg/kg of fentanyl with etomidate might significantly reduce the occurrence of airway reflexes in response to LMA insertion and increase the success rate of insertion. However, concurrent use of 1 mg/kg succinylcholine with etomidate might provide better results in terms of shortened time for the LMA insertion, jaw relaxation, and the success rate of LMA insertion than that of fentanyl.