A comparison of the suppression of cough reflex by intravenous lidocaine and remifentanil prior to extubation of the endotracheal tube / 대한마취과학회지

BACKGROUND: Cough reflex in response to extubation of the endotracheal tube is common; however, the effect of remifentanil on cough reflex is uncertain. Therefore, we evaluated the effect of lidocaine and remifentanil on cough reflex following extubation. METHODS: Forty adult patients scheduled to undergo elective surgery in two hours were enrolled in this study. All patients received a standard anesthetic protocol. Following surgery, the patients were randomly divided into two groups, Group L (n = 20), which received 1.5 mg/kg of 2% lidocaine intravenously, and Group R (n = 20), which received 0.5 microgram/kg remifentanil intravenously. Treatment was administered immediately after the patients opened their eyes, after which extubation was performed. We then evaluated breath holding and recorded the number of coughs at 5 minutes, 15 minutes and 30 minutes after extubation. In addition, we checked for sore throat 30 minutes after extubation. RESULTS: The number of coughs was significantly lower in Group R than in Group L at 5 minutes after extubation. However, there was no significant difference in the number of coughs in Group R and Group L at any other times evaluated. CONCLUSIONS: There are no significant differences in suppression of the cough reflex in response to treatment with lidocaine and remifentanil.

The correlation between actual blood concentration of propofol and the difference of estimated lean body mass with actual lean body mass in target controlled infusion / 대한마취과학회지

BACKGROUND: We evaluated the correlation between the difference of estimated lean body mass (LBM(E)) with actual lean body mass (LBM(A)) and actual blood concentration of propofol, hemodynamic variables and Bispectral index (BIS) during target controlled infusion (TCI) of propofol in Korean female patients who would take total intravenous anesthesia (TIVA) using propofol-remifentanil combination. METHODS: Eighty Korean women participated in this trial. Demographic data were collected and LBM(A) was measured using body mass analyzer. Target concentration of propofol was set at 6microgram/ml during induction and 3microgram/ml during maintenance. Hemodynamic variables and BIS were measured at 60 minutes after anesthetic induction. Peripheral blood sample was collected from a large forearm vein on the contralateral side of infusion for measurement of whole blood concentration of propofol at 60 minutes after anesthetic induction. Delta lean body mass (delta LBM) was obtained by subtracting LBM(A) from LBM(E). Correlation analyses were done between delta LBM and plasma propofol concentration, blood pressure, and BIS, respectively. RESULTS: Blood concentrations of propofol were 1.9-6.9microgram/ml. Mean plasma concentration of propofol was higher than target concentration. delta LBM had a positive correlation with actual plasma propofol concentration. delta LBM was not correlated with hemodynamic variables and BIS. CONCLUSIONS: TCI of propofol resulted in large variation in measured plasma concentration. We thought delta LBM was one of interpatient variation factors of propofol plasma concentration during TCI. We found that TCI of propofol using Schnider model would result in higher blood concentration than target concentration in Korean women.

The Comparison of Magnesium Sulfate and Remifentanil in Attenuating Hemodynamic Response to Endotracheal Intubation / 대한마취과학회지

BACKGROUND: Laryngoscopy and endotracheal intubation may cause tachycardia and hypertension. Magnesium directly inhibits the release of catecholamine from the adrenal medulla, with has a vasodilating effect. Remifentanil indirectly decreases the release of catecholamine by increasing the depth of anesthetic. The effects of magnesium sulfate and remifentanil at attenuating the sympathetic responses were compared during laryngoscopy and endotracheal intubation. METHODS: Eighty ASA class 1 or 2 patients, scheduled for elective surgery under general anesthesia, and requiring endotracheal intubation, were divided into four groups. The patient received either normal saline, 50 mg/kg magnesium sulfate, 1.0microgram/kg remifentanil or 25 mg/kg magnesium sulfate and 0.5microgram/kg remifentanil Groups C, M, R and MR, respectively, according to their assigned group. The specific drugs for each group were administered over a 30 second period prior to the induction of anesthesia with 2 mg/kg propofol and 1.5 mg/kg succinylcholine. The Systolic blood pressure, diastolic blood pressure and heart rate were recorded prior to induction (T1), immediately prior to intubation (T2), immediately after intubation (T3), and 1 and 3 minutes after intubation (T4 and T5, respectively). RESULTS: The percentage changes in the systolic blood pressure of groups M, R and MR were lower immediately after intubation than that of group C. The systolic blood pressures of groups M and MR increased from those at the baseline, but the systolic blood pressure of group R decreased from that at the baseline immediately after intubation. The heart rate of group M increased from that at the baseline, but the heart rate of group R decreased from that at the baseline immediately prior to intubation. CONCLUSIONS: The blood pressure immediately after endotracheal intubation was increased by the administration of magnesium sulfate, but the induced change was less than that of group C. The blood pressure was decreased by the administration of remifentanil immediately after endotracheal intubation. Magnesium sulfate caused tachycardia, but remifentanil caused bradycardia.