Objective To investigate pre-injected small dose of ephedrine's antagonism against propofol's suppression to cardiovascular system and fentanyl-induced cough reflex during the induction of general anesthesia.Methods 200 pregnant females requesting painless induced abortion with general anesthesia were randomized into two groups,the test group and the control group.Both the test and control groups were pre-injected with 6 mg of ephedrine or equal volume of saline,respectively.Then 1 g/kg of fentanyl was injected through peripheral venous within 2 seconds,and then 2 mg/kg of propofol was administered slowly by intravenous injection to induce anesthesia.Rate of cough reflex,degree of cough,arterial pressure,heart rate and SpO2 were recorded during the operation.Results After pre-injection of small dose of ephedrine,significant decrease in cough rate and degree was observed in the test group when compared to the control group,but no significant changes in hemodynamic responses were Observed between both groups during the induction of general anesthesia,such as MAP,heart rate,and SpO2.Conclusion Pre-injected small dose of ephedrine makes clear antagonistic effect on propofol's suppression to cardiovascular system and fentanyl-induced cough reflex during the induction of general anesthesia.

Objective To compare the hymodynamatic effects of anesthetic inductions with propofol(Group Ⅰ, 23 cases) and midazolam (Group Ⅱ,25 cases). Methods Forty-eight patients undergoing thoractic operation were classified randomly into two groups according to intravenous anesthetic agents used:propofol group (propofol 2 mg/kg) and midazolam group (midazolam 0.2 mg/kg).Anesthesia was induced with one of these two drugs followed by endotracheal intubation. The systaltic pressure (SBP),diastolic pressure(DBP), and heart rate (HR) were measured and recorded at following occasions:before induction, after induction,immediately,1,3,5, and 10 minutes after the tracheal intubation.Results After induction, SBP and DBP significantly decreased in both group.Immediatley and 1 minute after the tracheal intubation, SBP and DBP increased in group Ⅱ. Immediately after the intubation, HR also increased. But 5 and 10 minutes after the intubation, HR decreased in both groups. 10 minutes after the intubation, DBP increased in group Ⅰ while SBP still decreased in group Ⅱ.Conclusions Midazolam has a stable and long effect on the cardiovascular function, but could not depress the response of tracheal intubation effectively.And because the impaired cardiovascular function might be further compromised after induction with propofol in patients with cardiovascular disease, it is suggested that propofol be used quite carefully or not be used at all despite the fact that it may depress the response of tracheal intubation more effectively than midazolam.