BACKGROUND: We performed a prospective, randomized, controlled trial to compare the quality, hemodynamic response, and recovery index of laryngeal mask airway (LMA) insertion after either propofol alone or co-administration of alfentanil-propofol anesthesia. METHODS: Sixty patients (ASA 1 or 2, 17-63 years) were randomly allocated to control and experimental group. Control group(Group I) was received placebo (saline), experimental groups were received alfentanil 10microgram/kg (Group II), 20microgram/kg (Group III), 30microgram/kg (Group IV). RESULTS: Loss of consciousness and LMA insertion were more rapid in patients with alfentanil 30 microgram/kg group than control group (P<0.05). In alfentanil 20microgram/kg group, loss of consciousness was more rapid than control group. Also, there were significant differences in propofol induction dose, effect site concentration on induction, and propofol maintenance dose between control and experimental group (P<0.05). CONCLUSIONS: We conclude that co-adminstration of alfentanil-propofol, especially 30microgram/kg group, compares favorably with propofol alone, although LMA removal time is prolonged.
Alfentanil ; Anesthesia ; Hemodynamics ; Humans ; Laryngeal Masks* ; Propofol* ; Prospective Studies ; Unconsciousness

BACKGROUND: The aim of this randomized double-blinded study was to determine the optimal concentration of alfentanil with 0.15% ropivacaine for postoperative patient-controlled epidural analgesia. METHODS: Forty five patients undergoing major abdominal surgery under general anesthesia were assigned to groups receiving patient-controlled thoracic epidural analgesia with 0.15% ropivacaine + 45 microgram/ml alfentanil (Group I), 75microgram/ml alfentanil (Group II), 150 microgram/ml alfentanil (Group III). The incidence of side effects and additional analgesic use, VAS (visual analog pain scale) on resting and coughing, and patient's satisfaction were checked for 24 hours after a loading dose injection. RESULTS: The VAS on coughing and resting 1 hour after the loading dose injection were significantly lower in Groups II and III than in Group I. The patients in group II were more satisfied with the result than those in Group I. CONCLUSIONS: A combination of 0.15% ropivacaine and 75microgram/ml alfentanil for thoracic epidural analgesia after major abdominal surgery provides the best analgesia with minimal side effects and a higher level of patient's satisfaction.
Alfentanil* ; Analgesia ; Analgesia, Epidural* ; Anesthesia, General ; Cough ; Humans ; Incidence

BACKGROUND: The administration of short-acting opioids before emergence is useful for preventing emergence cough induced by an endotracheal tube. This study examined the clinically effective dose of alfentanil for suppressing cough during emergence from desflurane anesthesia. METHODS: Twenty-nine adult patients undergoing elective oral surgery were enrolled in this study. During emergence from anesthesia, the patients received alfentanil diluted in 10 ml normal saline when the end-tidal vol% of desflurane decreased to 3%. The initial alfentanil dose was 16 microg/kg. The alfentanil dose for consecutive patients, determined by Dixon's up-and-down method, increased or decreased by 2 microg/kg according to a previous patient's result. RESULTS: The 50% effective dose (ED50) of alfentanil for suppressing cough during emergence from desflurane anaesthesia was 9.3 +/- 1.5 microg/kg according to Dixon's up-and-down method. Isotonic regression revealed an ED50 and ED95 (95% confidence interval) of alfentanil 10.0 microg/kg (6.8-13.2 microg/kg) and 14.0 microg/kg (7.7-19.4 microg/kg), respectively. CONCLUSIONS: The ED95 of alfentanil for suppressing emergence cough was 14.0 microg/kg. A single bolus administration of alfentanil during emergence from anesthesia was useful for suppressing emergence cough.
Adult ; Alfentanil ; Analgesics, Opioid ; Anesthesia ; Cough ; Humans ; Isoflurane ; Surgery, Oral

BACKGROUND: Intraoperative alfentanil is known to increase the epileptic discharge in the adult seizure patients. This study hypothesized that alfentanil might localize an epileptogenic focus in pediatric seizure patients. METHODS: This study was performed in the pediatric seizure patients who undergo second-staged operation. Thirteen pediatric patients were enrolled and their epileptic foci were already suspected from first operation. After anesthetic induction, sevoflurane was maintained at 0.6% end-tidal concentration for study period. Electrocorticography (ECoG) was recorded for 5 minutes before and 5 minutes after alfentanil 20microgram/kg IV. During the ECoG recordings, the mean arterial pressure (MAP) and heart rate (HR) were continuously monitored. After the surgery, a pediatric neurologist analyzed the changes of spike frequencies of suspected ictal zone. The spike frequencies of suspected non-ictal zone were also calculated in five patients. The suspected ictal zone was defined as the most abundant spontaneous spiking area observed after first staged grid insertion. RESULTS: Alfentanil induced a significant increase in spike activity of suspected ictal zone in 12 out of 13 patients (median of 20 [ranged 10 to 100] vs 38 [ranged 20 to 100], P< 0.05). Alfentanil-induced increase of spike activity was prominent in the suspected ictal zone rather than non-ictal zone. There were no significant changes in the MAP and HR after administration of alfentanil. CONCLUSIONS: Alfentanil activates epileptiform activity of suspected ictal zone in pediatric patients with seizure disorder and can be used to assist in the localization of the epileptogenic focus during seizure surgery.
Adult ; Alfentanil* ; Arterial Pressure ; Epilepsy* ; Heart Rate ; Humans ; Seizures*

BACKGROUND: Alfentanil has been shown to act synergistically if combined with propofol, with or without nitrous oxide, or if combined with potent inhalation anesthetics. The goal of this study was to determine the dosing rate and target plasma concentration of propofol to supplement nitrous oxide in the presence of varying concentrations of alfentanil and to determine the optimal combination of propofol and alfentanil. METHODS: Sixty patients undergoing a total abdominal hysterectomy (TAH) were anesthetized with nitrous oxide, and given a target-controlled infusion (TCI) of alfentanil [target plasma concentrations of 0 (A0 group), 50 ng/ml (A50 group), and 100 ng/ml (A100 group)], and propofol at rates varied up and down depending on the bispectal index (BIS). The mean target concentration (Tc) and infusion rate of propofol according to changes of concentrations of alfentanil were determined. Recovery time (from infusion stop to eye opening) and side effects were compared. RESULTS: Induction time and recovery time were shortened in the A50 group and A100 group compared with the A0 group (P < 0.05). The infusion rate and mean target concentration of propofol were significantly lower in the A100 group (7.5 mg/kg/h, 3.4ng/ml) than the A0 (12.6 mg/kg/h, 4.5ng/ml) and A50 (10.2 mg/kg/h, 4.0ng/ml) groups (P < 0.01). Side effects did not differ among the three groups. CONCLUSIONS: The optimal blood propofol and plasma alfentanil concentration, with respect to satisfactory intraoperative anesthetic conditions and speed of recovery, are 4.0ng/ml and 50 ng/ml or 3.4ng/ ml and 100 ng/ml in TAH patients.
Alfentanil* ; Anesthetics, Inhalation ; Humans ; Hysterectomy* ; Nitrous Oxide ; Plasma ; Propofol*

BACKGROUND: The lower levels of cardiotoxicity and motor block make ropivacaine well suited as an epidural infusion for postoperative analgesia. This study examined the analgesic efficacy of an epidural infusion of ropivacaine alone and in combination with alfentanil after major abdominal surgery. METHODS: Thirty patients undergoing major abdominal surgery under general anesthesia were divided into two groups receiving patient-controlled thoracic epidural analgesia with 0.2% ropivacaine (Group I) and 0.15% ropivacaine +150 microgram/ml alfentanil (Group II). The motor block, side effects, VAS (visual analog pain scale) score on coughing and resting, additional analgesics use, and patient's satisfaction were checked for 24 hours after a loading dose injection. RESULTS: The VAS score in group II was significantly lower than in group I, and the patients in group II were more satisfied than those in group I (P < 0.05). However, there were more side effects in group II. CONCLUSIONS: Postoperative epidural infusion of 0.15% ropivacaine with 150 microgram/ml alfentanil is more effective than 0.2% ropivacaine only.
Alfentanil* ; Analgesia* ; Analgesia, Epidural ; Analgesics ; Anesthesia, General ; Cough ; Humans

BACKGROUND: Because desflurane can cause airway irritability when used to induce anesthesia, drugs aimed at reducing airway irritability. This study investigated the possible differences between lidocaine and alfentanil on the decrease in the airway irritability during desflurane inhaled induction. METHODS: 75 patients (25 in each groups) were assigned randomly to induce anesthesia with inhaled desflurane. The breathing circuit was primed with desflurane 6% in 50% O2 and 50% N2O. After pretreatment with 2% lidocaine (1 mg/kg), or alfentanil (10microgram/kg), or saline (7 ml) intravenously 2 minutes before inducing anesthesia, each patient breathed the gas mixture through a tight fitting facemask. The time to loss of consciousness, cough, laryngospasm, excitatory movement and hemodynamics were checked before and after inhalation. RESULTS: The time to loss of consciousness, cough and excitatory movement were lower significantly between in the control group and other groups, but there was no difference between the 2% lidocaine and alfentanil groups. The blood pressure and heart rate were lower in the alfentanil group, but the heart rate was similar. CONCLUSIONS: These results explain that intravenous 2% lidocaine appears to be useful. However, Intravenous alfentanil can also reduce the airway irritability and stabilize the hemodynamics significantly when desflurane is used to induce anesthesia.
Alfentanil* ; Anesthesia ; Blood Pressure ; Cough ; Heart Rate ; Hemodynamics* ; Humans ; Inhalation ; Laryngismus ; Lidocaine* ; Respiration ; Unconsciousness

BACKGROUND: The aim of this study was to examine the safety and efficacy of patient-controlled sedation (PCS) according to the lock-out time (LOT, 1 or 2 min) with a demand bolus of propofol and alfentanil fixed during a colonofiberscopy. METHODS: Fifty ASA physical status 1 or 2 patients who underwent a colonofiberscopy were enrolled in this study. They were provided with a PCS pump (Perfusor(R) fm, B Braun Germany, nominal infusion rate, NIR = 1,000 ml/h) containing propofol (9.1 mg/ml) and alfentanil (45.5microgram/ml) in order to self-administer a 2 ml bolus whenever they felt uncomfortable. The lock-out time (LOT) was set to 1 (n = 20, group 1) or 2 (n = 30, group 2) minutes. The Observer's Alertness/Sedation (OAA/S) score, D/A (delivery/attempt, %), blood pressure, heart rate, respiratory rate, SpO2, end tidal CO2 and bispectral index (BIS) were assessed and measured during and/or after the procedures. The verbal descriptive pain scores, as well as the patient's and endoscopist's satisfaction scale were assessed after the procedures. RESULTS: Intraoperative and postoperative pain scores, D/A, the patient's and endoscopist's satisfaction were similar in both groups. However, the lowest BIS values in group 1 was lower than in group 2 (70.3 +/- 12.2 and 77.6 +/- 6.8, respectively, P = 0.010). There were fewer patients whose lowest OAA/S score was <3 in group 2 (4/30) than in group 1 (11/20)(P = 0.002). CONCLUSIONS: With a demand bolus of propofol (18.2 mg) and alfentanil (91.0microgram) fixed, the incidence of over-sedation was higher at LOT 1 min than at LOT 2 min while the efficacy was similar in the PCS with a high NIR during the colonofiberscopy.
Alfentanil* ; Blood Pressure ; Germany ; Heart Rate ; Humans ; Incidence ; Pain, Postoperative ; Propofol* ; Respiratory Rate

BACKGROUND: The combination of propofol and alfentanil for nonrelaxant intubation produces hypotension and bradycardia. N2O, a commonly used inhaled anesthetic, has been known to augment the anesthetic depth in propofol anesthesia. Conversely, N2O was reported to increase the incidences of opioid-induced cough and rigidity. This study was designed to evaluate the effect of additional N2O on propofol requirement and intubating conditions. METHODS: Eighty healthy premedicated female patients were divided into N2O group (n = 40) and non-N2O group (n = 40). In each group, they were randomly assigned to four subgroups according to the propofol dose (1.0-2.5 mg/kg). With or without N2O (FiN2O = 0.5), propofol and 30mug/kg of alfentanil were administered during the induction of anesthesia. Expired concentrations of N2O were measured. Intubation was the attempted and intubating condition was scored (0-6). Incidences of cough and rigidity were also recorded. Dose of propofol for smooth intubation (score > 5) was analyzed and compared between groups. The conditions for smooth intubation were analyzed with variables (expired concentration of N2O, dose of propofol, age, incidences of hypotension, bradycardia, cough and rigidity) by logistic regression. RESULTS: The expired concentration of N2O was 33.0-3.8%. Propofol ED50 for smooth intubation was 1.67 mg/kg (1.26-2.19) in the N2O group and 2.27 mg/kg (1.78-3.47) in the non-N2O group. A smooth intubating condition was correlated well with increased concentrations of N2O and doses of propofol and inversely correlated with incidences of cough and rigidity. However, we failed to prove a significant difference in incidences of hypotension, bradycardia, cough and rigidity between the two groups. CONCLUSIONS: We cannot reduce the propofol requirement for smooth intubation without relaxant by using N2O. The success rate of intubation was increased by additional N2O.
Alfentanil ; Anesthesia ; Bradycardia ; Cough ; Female ; Humans ; Hypotension ; Incidence ; Intubation* ; Logistic Models ; Nitrous Oxide ; Propofol

BACKGROUND: Endotracheal fiberoptic bronchoscope intubation causes significant hemodynamic changes such as hypertension and tachycardia. The aim of this study was to evaluate the effects of alfentanil on cardiovascular response to endotracheal fiberoptic bronchoscope intubation in the patients anesthetized with N2O-O2-enflurane. METHODS: Forty seven healthy patients undergoing elective surgery requiring orotracheal intubation were randomly allocated to three groups and received either normal saline (control group), 8microgram/kg alfentanil (ALF8 group), or 4microgram/kg alfentanil (ALF4 group). Orotracheal intubation using a fiberoptic bronchoscope was carried out. Systolic, diastolic, and mean arterial blood pressures, and heart rates were monitored noninvasively and recorded at one-minute intervals. RESULTS: The percent change in mean arterial blood pressure from preanesthetic mean arterial blood pressure, was attenuated (P < 0.05 compared with the control group) in the ALF8 group 1 minute after intubation, but percent changes in mean arterial blood pressures from preanesthetic mean arterial blood pressure levels did not alter in the ALF4 or ALF8 groups between 1 and 5 minutes after intubation. Percent changes in heart rates from preanesthetic heart rates did not in either the ALF4 or ALF8 groups during the 5 minutes following intubation. CONCLUSIONS: These results show that alfentanil (8microgram/kg) attenuates blood pressure response to fiberoptic bronchoscopic intubation in patients anesthetized with N2O-O2-enflurane, but that it does not influence heart rate response.
Alfentanil ; Arterial Pressure ; Blood Pressure ; Bronchoscopes ; Heart Rate ; Hemodynamics ; Humans ; Hypertension ; Intubation ; Intubation, Intratracheal* ; Tachycardia