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: 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: 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 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: 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: 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 presence of pain during interventional pain management such as prolotherapy and intramuscular stimulation is stressful to patients and can affect the treatment outcome. We studied the safety and efficacy of two drug regimens: midazolam alone and midazolam/alfentanil for sedation anesthesia during prolotherapy and intramuscular stimulation. METHODS: Fifty three patients received either midazolam 0.04-0.08 mg/kg (Group M) or midazolam 0.01-0.02 mg/kg with alfentanil 4-8microgram/kg (Group A) for prolotherapy or intramuscular stimulation. We recorded the pain response, sedation score and side effects during the procedure, as well as amnesia, satisfaction and time to discharge after the procedure. RESULTS: Both drug regimens had significant sedation scores, amnesia and overall provided patient satisfaction. The treatment of pain was superior in Group A. Respiratory depression of three patients occurred in Group A. The time to discharge was longer in Group M. CONCLUSIONS: Midazolam and midazolam/alfentanil used for sedation anesthesia during prolotherapy and intramuscular stimulation were both effective; however, midazolam alone was the safer approach.
Alfentanil ; Amnesia ; Anesthesia* ; Humans ; Midazolam* ; Pain Management ; Patient Satisfaction ; Respiratory Insufficiency ; Treatment Outcome

BACKGROUND: We investigated the effects of a magnesium sulfate pretreatment on intubating conditions and cardiovascular responses during rapid sequence tracheal intubation (RSI) in this double-blind randomized study. METHODS: Adult patients (n = 154) were randomly allocated to a rocuronium-0.6, rocuronium-0.9, or magnesium group. The magnesium group was pretreated with 50 mg/kg MgSO4, and the other two groups received the same volume of isotonic saline. Anesthesia was induced with alfentanil, propofol, and either 0.6 mg/kg (rocuronium-0.6 and magnesium groups) or 0.9 mg/kg (rocuronium-0.9 group) rocuronium. An anesthesiologist, blinded to the group assignments, performed RSI and assessed the intubating conditions. Systolic arterial pressure (SAP) and heart rate (HR) were recorded before the magnesium sulfate or normal saline was administered, before anesthesia induction, before intubation, and every minute after intubation for 5 min. RESULTS: Airway features were similar among the three groups. The intubating conditions were improved significantly in the magnesium group (P < 0.001) compared with the other two groups. Significant increases in SAP at 1 min after intubation were observed in the rocuronium-0.6 and -0.9 groups when compared with the magnesium group (P < 0.05). HR was comparable among the three groups (P > 0.05). No hypertensive episode occurred during the immediate post-intubation period in the magnesium group (P = 0.001), and tachycardia occurred most frequently in the rocuronium-0.6 group (P < 0.05). CONCLUSIONS: MgSO4 administered prior to RSI using alfentanil, propofol, and rocuronium may improve intubating conditions and prevent post-intubation hypertension.
Adult ; Alfentanil ; Androstanols ; Anesthesia ; Arterial Pressure ; Heart Rate ; Humans ; Hypertension ; Intubation ; Magnesium ; Magnesium Sulfate ; Propofol ; Tachycardia

BACKGROUND: Recent studies suggest that additional use of alfentanil could provide the best condition for the laryngeal mask airway (LMA) insertion. The aim of this study is to compare the median effective dose (ED50) of propofol for the classic LMA insertion and the insertion condition following between fentanyl and alfentanil adjuvant. METHODS: We enrolled 53 patients scheduled for minor surgery under general anesthesia. Patients were randomly allocated to the fentanyl group (n = 24) and the alfentanil group (n = 29) in double blind manner. For fentanyl group, 1microgram/kg of fentanyl was injected intravenously 90 sec before propofol. The afentanil group received 4microgram/kg of alfentanil and propofol coincidently. The insertion of LMA was attempted 90 sec after propofol administration. In accordance with Dixon's up-and-down method, the dose of propofol for consecutive patients in each group was varied with increments or decrements of 0.5 mg/kg based on the previous insertion results of patients. RESULTS: In the fentanyl and alfentanil group, the ED50 of propofol for LMA insertion according to Dixon's method was 2.0 +/- 0.3 mg/kg and 1.8 +/- 0.3 mg/kg, respectively. In addition, the ED50 of propofol of the fentanyl and alfentanil group according to probit regression model, 1.7 mg/kg (95% confidence interval, 1.2-2.2) and 1.7 mg/kg (1.3-2.0) were calculated respectively. There is no significant difference between the two groups. CONCLUSIONS: There was no significant difference in propofol ED50 for insertion of LMA and insertion condition between the alfentanil and the fentanyl group.
Alfentanil* ; Anesthesia, General ; Fentanyl* ; Humans ; Laryngeal Masks ; Propofol* ; Surgical Procedures, Minor

BACKGROUND: The intravenous injection of rocuronium bromide is often painful, and different methods have been used to minimize the incidence and severity of this pain. This study determined the effective dose of alfentanil to minimize the injection pain of rocuronium and the cardiovascular response after endotracheal intubation. METHODS: Eighty ASA physical status 1 and 2 adult patients were divided into four groups. Sixty seconds before administering rocuronium 0.6 mg/kg, the groups were given 10 ml of intravenous normal saline or alfentanil 10, 15, and 20microgram/kg. Pain was assessed after rocuronium injection. The mean arterial pressure and heart rate were measured before induction and before and after intubation. RESULTS: Both 15 and 20microgram/kg alfentanil minimized the rocuronium injection pain, although 20microgram/kg alfentanil caused an undesirable decrease in the mean arterial pressure. CONCLUSIONS: A 15microgram/kg bolus of alfentanil may be useful for minimizing the rocuronium injection pain and blunting the cardiovascular response after endotracheal intubation.
Adult ; Alfentanil ; Androstanols ; Arterial Pressure ; Heart Rate ; Humans ; Incidence ; Injections, Intravenous ; Intubation, Intratracheal