BACKGROUND: The Vital capacity technique is known to have some advantages over the tidal volume technique during inhalation induction of anesthesia.The aim of this study was to compare the incidence of withdrawal movement associated with the intravenous administration of rocuronium 0.3 mg/kg in children during inhalation induction with sevoflurane using the tidal volume and vital capacity techniques. METHODS: We randomly assigned 130 patients (aged 5-12 years) to either tidal volume (group T) or vital capacity (group V) groups for inhalation induction with sevoflurane.Rocuronium 0.3 mg/kg was administrated after loss of the eyelash reflex.The time to loss of the eyelash reflex was recorded and adverse events during induction were documented.The patient's response to rocuronium injection was graded using a four-point scale. RESULTS: No significant differences were observed between the groups with respect to age, weight, and gender.The time to loss of the eyelash reflex was more rapid in group V than in group T (P < 0.05).Excitatory movement developed more frequently in group T, and no significant differences were found in the incidence of other adverse events between the groups.The incidence of withdrawal movement associated with the injection of rocuronium was significantly lower in group V compared to group T (30 vs. 60%; P < 0.05). CONCLUSIONS: Inhalation induction with sevoflurane using the vital capacity technique decreased the incidence of withdrawal movement during the injection of rocuronium compared to the tidal volume technique.
Administration, Intravenous ; Androstanols ; Child ; Humans ; Incidence ; Inhalation ; Methyl Ethers ; Reflex ; Tidal Volume ; Vital Capacity

BACKGROUND: Intravenous injection of rocuronium is associated with withdrawal responses which are attributable to the pain from the injection of rocuronium. Several methods have been proposed to abolish and attenuate rocuronium-induced pain. We hypothesized priming dose of rocuronium could reduce withdrawal responses associated with administering a second large dose of rocuronium for tracheal intubation. We compared the efficacy of the priming dose technique of rocuronium with intravenous lidocaine as a pre-treatment for the prevention of withdrawal responses associated with rocuronium injection. METHODS: We recruited 150 patients aged between 18 and 60 years, ASA physical status 1 or 2, who were going to undergo elective surgery requiring general anesthesia. Patients were allocated into three groups. Group C received normal saline, Group L received lidocaine 1 mg/kg, and Group P received rocuronium 0.06 mg/kg 2 minutes before administering a second large dose of rocuronium for tracheal intubation. After the loss of consciousness, rocuronium 0.6 mg/kg was administered intravenously over 10 seconds for tracheal intubation. The withdrawal responses to the injection of rocuronium were evaluated. RESULTS: The incidence of withdrawal responses associated with rocuronium injection for tracheal intubation was 56, 50, 24% in group C, group L, and group P, respectively. The incidence of withdrawal responses was lower in group P than group C and group L, but there was no difference between group L and group C. CONCLUSIONS: Priming dose technique is a useful clinical method to alleviate withdrawal responses associated with rocuronium injection.
Administration, Intravenous ; Aged ; Androstanols ; Anesthesia, General ; Humans ; Incidence ; Injections, Intravenous ; Intubation ; Lidocaine ; Unconsciousness

OBJECTIVETo compare the cardiorespiratory factors and surgical conditions during total intravenous anesthesia for prolonged laparoscopic pelvic surgery with or without supplemental muscle relaxants.

METHODSForty female ASA I or II patients undergoing laparoscopic pelvic surgeries were randomized into two groups A and B, both with standardized anesthesia via a intravenous bolus injection of rocuronium (0.6 mg/kg). The patients in group B received continuous rocuronium infusion upon observation of one TOF twitch response with the T1 value maintained within 0-10% and rocuronium withdrawal at 20 to 30 min before the completion of the surgery. The patients in group A received no supplemental muscle relaxants. The cardiorespiratory parameters were measured during the operation. The respiratory system compliance (Ceff rs) was calculated as the quotient of the tidal volume (VT) and peak inspiratory pressure (PIP), and the operative conditions were graded by the operating gynecologist.

RESULTSThe cardiorespiratory parameters significant increased and Ceff rs decreased after pneumoperitoneum, but no significant differences were found between the two groups. The surgical conditions were also comparable between the two groups, but the duration of intubation and the operating time were significantly shorter in the group A.

CONCLUSIONPneumoperitoneum severely affects the cardiorespiratory parameters during laparoscopy, which can not be lessened by neuromuscular block agents. A single intubating dose of rocuronium can suffice the requirement of prolonged gynecologic laparoscopic surgery.

Androstanols ; administration & dosage ; Anesthesia, Intravenous ; Female ; Gynecologic Surgical Procedures ; Humans ; Laparoscopy ; methods ; Neuromuscular Nondepolarizing Agents ; administration & dosage

OBJECTIVETo study the feasibility of using Narcotrend (NCT) in monitoring the anesthetic depth during endotracheal intubation in sevoflurane anesthesia.

METHODSThirty ASA I-II patients (aged 20-49 years) undergoing gynecologic surgery under general anesthesia with tracheal intubation were randomized into sevoflurane group (n=15) and sevoflurane plus rocuronium group (n=15). In the former group, anesthesia was induced with sevoflurane at the primary concentration of 8% till the final end expiratory concentration reaching 2 MAC(minimum alveolar concentration) for 3 min, followed then by tracheal intubation and further observation of the indicators for another 3 min. The patients in sevoflurane plus rocuronium group received identical anesthesia procedures except for the administration of intravenous injection of rocuronium (0.6 mg/kg) after the loss of eyelash reflex. The NCT, BIS and hemodynamics were recorded during the process.

RESULTSNo significant differences were noted in NCT, bispectral index (BIS), MAP and heart rate before tracheal intubation between the two groups (P>0.05). The NCT and BIS increased significantly after tracheal intubation in sevoflurane group (P<0.05), but remained below 60. No significant changes in NCT and BIS occurred during intubation in sevoflurane plus rocuronium group (P>0.05). The mean arterial pressure (MAP) and heart rate were significantly increased in both groups after tracheal intubation in comparison with those before tracheal intubation (P<0.05), but the increment in sevoflurane group was significantly greater (P<0.05).

CONCLUSIONNCT may reflect the changes of the anesthetic depth resulting from the nociceptive stimulus of tracheal intubation in sevoflurane- induced anesthesia. NCT and BIS can not serve such a purpose in combined anesthesia with sevoflurane and rocuronium.

Adult ; Androstanols ; administration & dosage ; Anesthesia ; Anesthetics, Intravenous ; administration & dosage ; Hemodynamics ; Humans ; Intubation, Intratracheal ; methods ; Methyl Ethers ; administration & dosage ; Middle Aged ; Monitoring, Intraoperative ; methods ; Young Adult

OBJECTIVETo compare the dose requirements of continuous infusion of rocuronium and atracurium throughout orthotopic liver transplantation (OLT) in humans.

METHODSTwenty male patients undergoing liver transplantation were randomly assigned to two comparable groups of 10 patients each to receive a continuous infusion of rocuronium or atracurium under intravenous balanced anesthesia. The response of adductor pollicis to train-of-four (TOF) stimulation of unlar nerve was monitored. The infusion rates of rocuronium and atracurium were adjusted to maintain T1/Tc ratio of 2%~10%. The total dose of each drug given during each of the three phases of OLT was recorded.

RESULTSRocuronium requirement, which were (0.468+/-0.167) mg/(kg.h) during the paleohepatic phase, decreased significantly during the anhepatic phase to (0.303+/-0.134) mg/(kg.h) and returned to the initial values at the neohepatic period ((0.429+/-0.130) mg/(kg.h)); whereas atracuruim requirements remained unchanged during orthotopic liver transplantation.

CONCLUSIONSThis study showed that the exclusion of the liver from the circulation results in the significantly reduced requirement of rocuronium while the requirement of atracurium was not changed, which suggests that the liver is of major importance in the clearance of rocuronium. A continuous infusion of atracurium with constant rate can provide stable neuromuscular blockade during the three stages of OLT.

Adult ; Aged ; Androstanols ; administration & dosage ; pharmacokinetics ; Atracurium ; administration & dosage ; pharmacokinetics ; Humans ; Infusions, Intravenous ; Intraoperative Period ; Liver ; metabolism ; Liver Transplantation ; Male ; Middle Aged ; Neuromuscular Nondepolarizing Agents ; administration & dosage ; pharmacokinetics

BACKGROUNDTarget-controlled infusion (TCI) has been recently developed and successfully implemented in clinical practice. The current study was to estimate the population pharmacokinetics of rocuronium TCI in adult patients using nonlinear mixed-effects model (NONMEM), and to investigate the influence of relevant factors in adult patients.

METHODSFourteen ASA I-II patients undergoing elective laparoscopy operation with general anesthesia were included. After induction, all patients received rocuronium by TCI system. The beginning target plasma concentration (Cpt) was 2.0 µg/ml, then increased Cpt according to the neuromuscular transmission monitoring. The endpoint of Cpt was determined when the T₁ scale was blocked by 90% - 95%. TCI rocuronium was stopped 30 minutes before the end of the operation. Arterial blood was drawn before anesthesia at 0, 2, 4, 6, 8, 10, 15, 20, 30, 45, 60, 120, 180, 240 and 360 minutes after the infusion of rocuronium was stopped for the analysis of plasma concentrations of rocuronium by liquid chromatography-mass spectrometry/mass spectrometry (LC-MS/MS). The population pharmacokinetics analysis was performed using NONMEM program.

RESULTSThe pharmacokinetics of TCI rocuronium in adult patients was best described by a three-compartment model. Pharmacokinetic parameters were clearance (CL)₁ = 0.205 L/min, CL₂ = 0.324 L/min, CL₃ = 0.0292 L/min, volumes of distribution (V)₁ = 4.00 L, V₂ = 2.28 L, V₃ = 4.26 L, Vdss = 10.54 L. Both age and weight as covariates affected the pharmacokinetic parameters. V₁ and CL₁ were negatively correlated with patient age. CL₁ was positively correlated with weight.

CONCLUSIONSNo pharmacokinetic change was noted when rocuronium was administered via TCI. Both age and weight as covariates affected the pharmacokinetic parameters.

Adolescent ; Adult ; Aged ; Aged, 80 and over ; Androstanols ; administration & dosage ; pharmacokinetics ; Female ; Humans ; Infusion Pumps ; Male ; Middle Aged ; Young Adult

OBJECTIVETo determine the half-effective dose (IED50) of rocuronium for intratracheal intubation in female patients of different ages by sequential experiments and evaluate the effect of age on IED50 of rocuronium.

METHODSForty ASA class I-II female patients undergoing elective surgery under general anesthesia were randomly divided (n = 20) into young patient group and elderly patient group. The intratracheal intubation dose was divided into 4 grades by geometric progression, namely 0.24, 0.29, 0.35, and 0.42 mg/kg in the young patient group and 0.22, 0.26, 0.31, and 0.37 mg/kg in the elderly group. The IED(50) and 95% confidence interval (95%CI) of rocuronium during intubation in both groups were determined by sequential experiments.

RESULTSThe IED50 was 0.284 mg/kg in the elderly patient group, which was 91% that of in the young patient group (0.312 mg/kg), showing significant difference between the two groups (P < 0.05).

CONCLUSIONThe IED50 of rocuronium is significantly lower in elderly female patients than in young female patients, suggesting the necessity of reducing the dose of rocuronium accordingly in anesthesia induction in elderly female patients.

Adolescent ; Adult ; Age Factors ; Aged ; Aged, 80 and over ; Androstanols ; administration & dosage ; Dose-Response Relationship, Drug ; Female ; Humans ; Intubation, Intratracheal ; Middle Aged ; Neuromuscular Nondepolarizing Agents ; administration & dosage ; Sex Factors

OBJECTIVETo define the ideal time window for intubation after rocuronium administration during target-controlled infusion (TCI) ofpropofol and sulfentanil.

METHODSOne hundred and twenty elective surgical patients (age range 18-55 years) were randomized into 4 groups (n=30) according to the intubation time after administration of the muscle relaxant. Patients with predicted difficult airway were excluded. General anesthesia was induced by TCI of propofol and sulfentanil. A senior anesthesiologist blinded for the randomization performed the intubations at 1, 2, 3, or 4 min after injection of rocuronium, and the vocal card visibility was evaluated upon full exposure of the vocal cord and the intubation conditions assessed according to Cooper's score.

RESULTSThe intubation conditions were excellent or good in all patients, but the vocal cord visibility at 2-4 min differed significantly from that at 1 min after rocuronium administration (P<0.01). Suppression of the neuromuscular function 1 min after rocuronium administration differed significantly from that at other time points (P<0.01).

CONCLUSIONThe condition of vocal cord can be more suitable for intubation at 2-4 min than at 1 min after rocuronium administration as the ideal time window for intubation during TCI of propofol and sulfentanil.

Adolescent ; Adult ; Androstanols ; administration & dosage ; Anesthetics, Intravenous ; administration & dosage ; Humans ; Infusions, Intravenous ; Intubation ; methods ; Middle Aged ; Neuromuscular Nondepolarizing Agents ; administration & dosage ; Propofol ; administration & dosage ; Single-Blind Method ; Sufentanil ; administration & dosage ; Time Factors ; Vocal Cords ; drug effects ; Young Adult

PURPOSE: The incidence of pain induced withdrawal movement following intravenous injection of rocuronium is high. This randomized, double-blind, placebo-controlled study was designed to evaluate the effect of pretreatment of remifentanil on the withdrawal movements due to intravenous injection of rocuronium during anesthetic induction. MATERIALS AND METHODS: Ninety adult female patients undergoing thyroidectomy were randomly allocated to three groups. Each patient intravenously received one of three solutions of equal volume (4 mL): normal saline (Group I, n=30), 0.5 microgram/kg remifentanil (Group II, n=30) or 1 microgram/kg remifentanil (Group III, n=30). Thirty seconds after remifentanil administration, anesthesia was induced with 5 mg/kg IV thiopental. Twenty seconds after thiopental injection, 0.6 mg/kg IV rocuronium was administered (injection rate of 0.5 mL/sec) and patients' withdrawal movements were assessed. Mean arterial pressure (MAP) and heart rate were assessed on arrival in the operation room, before the tracheal intubation and immediately, 1 and 2 min after the tracheal intubation. RESULTS: The incidence of withdrawal movements was significantly lower in both of the remifentanil groups (3 and 0% in Group II and III, respectively) than in the saline group (70%). Remifentanil attenuated the increase of heart rate and MAP immediately and 1 min after the tracheal intubation. CONCLUSION: The pretreatment with 0.5 and 1.0 microgram/kg remifentanil of bolus doses prevented the withdrawal movements caused by rocuronium injection, and effectively blunted cardiovascular activation following tracheal intubation.
Adult ; Aged ; Analgesics, Opioid/administration & dosage/therapeutic use ; Androstanols/administration & dosage/*adverse effects ; Female ; Humans ; Injections, Intravenous/adverse effects ; Middle Aged ; Pain/etiology/*prevention & control ; Piperidines/administration & dosage/*therapeutic use

OBJECTIVETo evaluate the effect of dexmedetomidine (Dex) on bispectral index (BIS) and auditory evoked potential index (AAI) during anesthesia with target controlled infusion (TCI) of propofol and remifentanyl.

METHODSThirty adult patients (ASA I approximate, equalsII) who were scheduled for elective thyroidectomy were monitored with BIS, AAI, ECG, blood pressure, end-tidal CO(2), and pulse oximeter before and during anesthesia. Anesthesia was induced by TCI with propofol 4 mg/L and remifentanyl 1 mu g/kg. After loss of consciousness the patients were intubated after rocuronium 0.6 mg/kg intravenous injection, remifentanyl was then infused at 0.2 microg/(kg x min)(-1) and propofol infusion (Ct) was titrated to maintain a BIS value at 50 +/- 3. At 10 min after stabilization of anesthesia the patients were randomly and double-blindly divided into 2 groups: Group D (n=15) received Dex 0.4 mu g/kg iv administered over 5 min and Group C (n=15) received equal volume of normal saline. Values of BIS, AAI, MAP, HR were recorded every 2 min within 20 min after the administration of the drugs.

RESULTSBefore anesthesia the BIS index was 90 +/- 2 in Group D and 92 +/- 2 in Group C, AAI was 81 +/- 1 in Group D and 78 +/- 1 in Group C. In anesthesia with target controlled infusion of propofol, BIS index showed a significant decrease with the i.v. administration of Dex 0.4 microg/kg, while AAI remained unchanged. In Group C, both of BIS and AAI remained unchanged after saline injection.

CONCLUSIONDuring propofol and remifentanyl anesthesia, after the administration of Dex, BIS value demonstrates a predominant decrease, whereas AAI shows no changes.

Adrenergic alpha-Agonists ; administration & dosage ; Adult ; Androstanols ; administration & dosage ; Anesthetics, Combined ; administration & dosage ; Anesthetics, Intravenous ; administration & dosage ; Dexmedetomidine ; administration & dosage ; pharmacology ; Double-Blind Method ; Evoked Potentials, Auditory ; drug effects ; Female ; Humans ; Infusions, Intravenous ; methods ; Male ; Medetomidine ; pharmacology ; Middle Aged ; Monitoring, Intraoperative ; methods ; Neuromuscular Nondepolarizing Agents ; administration & dosage ; Piperidines ; administration & dosage ; pharmacology ; Propofol ; administration & dosage ; pharmacology ; Thyroidectomy