Effects of Remifentanyl on Induction Characteristics and MAC of Desflurane During Endotracheal Intubation

Objective: To study the Effects of remifentanyl on induction characteristics and MAC of desflurane during endotracheal intubation.Method: Forty-two ASAⅠ～Ⅱpatients,aged 18～72,undergoing elective lower abdominal operation under general anesthesia,were randomly divided into two groups according to the methods for anesthetic induction.D group: desflurane was used for endotracheal intubation.R group: remifentanyl combined with desflurane was chosen for induction.The time for loss of consciousness,the incidence of coughing and laryngospasm,MAP and HR as well as MAC of desflurane during endotracheal intubation(MACEI50) were recorded.Results: Loss of consciousness was in 2.3±0.5 min and 2.4±0.3 min,respectively.The rapid increase of desflurane concentration resulted in coughing(60%),laryngospasm(52%),and significant increments of MAP and HR during induction in D group.On the contrary,coughing and laryngospasm were rare,and MAP and HR remained stable in R group.MACEI50 was significantly reduced from 2.1±0.4 in D group to 0.9±0.2 in R group.Conclusion: Induction of anesthesia with both only desflurane and desflurane combined with remifentanyl are rapid,but the former can lead to a high incidence of airway and cardiovascular stimuli.Remifentanyl attenuates airway and cardiovascular response to desflurane and produces a decrease in the MACI50 of desflurane.