STUDY DESIGN: Prospective, randomized, double blind, placebo-controlled study.PURPOSE: To compare clonidine and pregabalin with placebo for the attenuation of postoperative pain after thoracolumbar spinal surgery and instrumentationOVERVIEW OF LITERATURE: Spine surgery is associated with moderate to severe postoperative pain that needs to be controlled to improve patient’s outcome. Alpha 2 agonists (e.g., clonidine) and gabapentenoids (e.g., pregabalin) are successfully used as part of a multimodal analgesic regimen.METHODS: Total 75 patients were enrolled and randomly allocated into three groups. Group P received pregabalin (150 mg), group C received clonidine (150 mcg), and group N received placebo 90 minutes preoperatively. A standard anesthesia protocol comprising fentanyl, thiopentone, vecuronium, nitrous oxide, and oxygen in isoflurane was used for all patients. Postoperative recovery profile, pain, time for first analgesic, 24-hour analgesic requirement, sedation, and hemodynamic parameters were noted.RESULTS: Recovery profile was similar in all three groups; however, the patients in group P and C were more sedated (p<0.05). Group N patients had a higher Visual Analog Scale (VAS) score (p<0.05) and the time for first analgesic was also lower (p=0.02). Postoperative (24-hour) analgesic requirement was maximum in group N, followed by that in group C and group P. The VAS score was highest in the control group; however, after 12 hours, it was similar in all groups.CONCLUSIONS: Postoperative pain and analgesic requirement is significantly attenuated by preoperative administration of a single dose of clonidine (150 mcg) or pregabalin (150 mg); pregabalin was more effective. Thus, their use offers a reasonable strategy for pain management in patients undergoing spine surgery.
Analgesics ; Anesthesia ; Clonidine ; Fentanyl ; Hemodynamics ; Humans ; Isoflurane ; Nitrous Oxide ; Oxygen ; Pain Management ; Pain, Postoperative ; Pregabalin ; Prospective Studies ; Spine ; Thiopental ; Vecuronium Bromide ; Visual Analog Scale

BACKGROUND: The concept of the effect-site concentration of anesthetic agents is important. The effect compartment model can be explained using the concepts of effect-site concentration and effect-site equilibration rate constant (k e0). This study confirms that the time-to-peak effect (tpe ) can be measured easily in clinical practice by applying a priming dose and train-of-four (TOF) during general anesthesia induction, and k e0 can be calculated from the tpe of the four muscle relaxants that are commonly used in general anesthesia. METHODS: Eighty patients who received general anesthesia were divided into the succinylcholine, rocuronium, atracurium, or vecuronium groups. Priming doses of muscle relaxants were administered. The effects of muscle relaxants were quantified by recording the twitch response of the adductor pollicis muscle after stimulating the ulnar nerve. The tpe was measured at the lowest TOF value. k e0 was calculated from the measured tpe . RESULTS: The k e0 values of the succinylcholine, rocuronium, atracurium, and vecuronium groups were 0.076 (0.030)/min, 0.228 (0.122)/min, 0.062 (0.011)/min, and 0.077 (0.019)/min, respectively. CONCLUSIONS: It is possible to estimate k e0 from the tpe of muscle relaxants using a priming dose and TOF during general anesthesia induction.
Anesthesia, General* ; Anesthetics ; Atracurium ; Humans ; Succinylcholine ; Ulnar Nerve ; Vecuronium Bromide

BACKGROUND: The differences between neuromuscular blocking (NMB) drugs on the efficacy of intraoperative motor-evoked potential (MEP) monitoring have not been established through clinical study. We compared the effects of vecuronium and cisatracurium on the efficacy of intraoperative MEP monitoring. METHODS: We enrolled 72 patients who had undergone neurosurgery with MEP monitoring. We randomly allocated the subjects into one of two groups, in whom we maintained continuous intravenous vecuronium (Group V) or cisatracurium (Group C) infusion during the surgeries; the target partial NMB for maintenance was T1/Tc 50% (T1, first twitch of TOF response; Tc, control response of T1 before NMB drug injection). We compared the means and coefficients of variation (CV, %) of all measured MEP amplitudes and the frequencies of NMB drug dose changes. RESULTS: The means and CVs of MEP amplitude and latency in all four limbs did not differ significantly between the groups, although we did change the continuous NMB drug doses in group V significantly less often than in group C. CONCLUSIONS: There were no significant differences between vecuronium and cisatracurium on the MEP variability and mean amplitudes. However, cisatracurium needed more frequent dose changes to maintain T1/Tc 50%.
Clinical Study ; Extremities ; Humans ; Intraoperative Neurophysiological Monitoring ; Neuromuscular Blockade ; Neurosurgery* ; Vecuronium Bromide*

The duration of the effect of muscle relaxants is extended in patients with acquired immunodeficiency syndrome (AIDS); however, a specific mechanism for this effect has not yet been discovered. In addition, streptomycin is known to prolong the action of muscle relaxants by blocking activity at neuromuscular junctions. Here, we report the case of patient with AIDS taking streptomycin for pulmonary tuberculosis for which sugammadex was effective in reversing prolonged paralysis induced by rocuronium and vecuronium for video-assisted thoracoscopic surgery (VATS) lung wedge resection.
Acquired Immunodeficiency Syndrome* ; Humans ; Lung ; Neuromuscular Blockade* ; Neuromuscular Junction ; Paralysis ; Streptomycin* ; Thoracic Surgery, Video-Assisted ; Tuberculosis, Pulmonary ; Vecuronium Bromide

BACKGROUND: Magnesium is known to reduce the requirement of analgesic agents by blocking calcium channels that exist at the neuronal and neuromuscular junctions. However, former studies have shown inconsistent results regarding this concept. Therefore, we investigated the effects of magnesium on remifentanil requirements for achieving hemodynamic stabilization in patients undergoing laparoscopic gastrectomy. METHODS: Laparoscopic gastrectomy patients (n = 30) were randomly divided into two groups. Group M received 50 mg/kg of magnesium sulfate for 15 minutes prior to the induction of anesthesia. Then, 20 mg/kg/h of magnesium was administered during the operation time. Group N was administered the same amount of saline. Anesthesia was maintained with intravenous propofol and remifentanil injection. Vecuronium (0.1 mg/kg) was administered before intubation, and an additional 0.02 mg/kg was administered if a T1 twitch response was observed during surgery. Anesthetic time was standardized to provide an appropriate comparison of all patients. During 100 minutes, total anesthetic requirements and anesthetic requirements at every 10 minutes were analyzed. Postoperative pain was controlled with a patient controlled analgesia device. RESULTS: The remifentanil and vecuronium requirements during 100 minutes were significantly lower in Group M. There was no significant difference in propofol requirements between the two groups. No significant difference was observed in mean arterial pressure and heart rate. Postoperative VAS, PONV, or shivering also did not show any difference between the two groups. CONCLUSIONS: Magnesium reduced remifentanil and vecuronium requirements but not propofol requirements. Magnesium seems to have antinociceptic properties and reduces remifentanil requirements.
Analgesia, Patient-Controlled ; Analgesics ; Anesthesia ; Arterial Pressure ; Calcium Channels ; Gastrectomy* ; Heart Rate ; Hemodynamics* ; Humans ; Intubation ; Laparoscopy* ; Magnesium ; Magnesium Sulfate* ; Neuromuscular Junction ; Neurons ; Pain, Postoperative ; Postoperative Nausea and Vomiting ; Propofol ; Shivering ; Vecuronium Bromide

The hypothesis of this study was that diabetes-induced desensitization of rat soleus (SOL) and extensor digitorum longus (EDL) to non-depolarizing muscle relaxants (NDMRs) depends on the stage of diabetes and on the kind of NDMRs. We tested the different magnitude of resistance to vecuronium, cisatracurium, and rocuronium at different stages of streptozotocin (STZ)-induced diabetes by the EDL sciatic nerve-muscle preparations, and the SOL sciatic nerve-muscle preparations from rats after 4 and 16 weeks of STZ treatment. The concentration-twitch tension curves were significantly shifted from those of the control group to the right in the diabetic groups. Concentration giving 50% of maximal inhibition (IC50) was larger in the diabetic groups for all the NDMRs. For rocuronium and cisatracurium in both SOL and EDL, IC50 was significantly larger in diabetic 16 weeks group than those in the diabetic 4 weeks group. For SOL/EDL, the IC50 ratios were significantly largest in the diabetic 16 weeks group, second largest in the diabetic 4 weeks group, and smallest for the control group. Diabetes-induced desensitization to NDMRs depended on the stage of diabetes and on the different kind of muscles observed while was independent on different kind of NDMRs. The resistance to NDMRs was stronger in the later stage of diabetes (16 versus 4 weeks after STZ treatment). Additionally, when monitoring in SOL, diabetes attenuated the actions of neuromuscular blockade more intensely than that in EDL. Nonetheless, the hyposensitivity to NDMRs in diabetes was not relevant for the kind of NDMRs.
Animals ; Diabetes Mellitus, Experimental* ; Inhibitory Concentration 50 ; Muscles* ; Neuromuscular Blockade ; Neuromuscular Junction ; Neuromuscular Nondepolarizing Agents ; Rats* ; Streptozocin ; Vecuronium Bromide

BACKGROUND: Muscle relaxants induce vascular smooth muscle relaxation by inducing synthesis of the prostaglandins that influence vasomotor tone. However, the effects of muscle relaxants on endothelial cells and tissues following injury by reactive oxygen species (ROS) are unclear. We tested the effects of the muscle relaxants vecuronium and rocuronium on impaired acetylcholine (ACh)-induced relaxation following induction of ROS in rabbit aorta in vitro. METHODS: Isolated rabbit abdominal aortic ring segments were pretreated with vecuronium or rocuronium at 10(-4), 3 x 10(-4), 10(-3) or 3 x 10(-3) M, with or without inhibitors of Cu/Zn superoxide dismutase (diethyldithiocarbamate; DETCA, 0.8 mM) or catalase (3-amino-1,2,4-triazole; 3AT, 50 mM). All groups of aortic rings were then exposed to ROS generated by electrolysis in the organ bath medium (Krebs-Henseleit solution). The effects of vecuronium and rocuronium on ROS-induced impairment of relaxation induced by ACh (10(-6) M) were assessed. RESULTS: Aortic rings treated with vecuronium or rocuronium at 10(-4), 3 x 10(-4), 10(-3) or 3 x 10(-3) M preserved the capacity for ACh-induced endothelial relaxation following ROS exposure in a dose-dependent manner. Pretreatment with DETCA partially inhibited the protective effects of vecuronium and rocuronium on ACh-induced relaxation (P < 0.001), but pretreatment with 3AT had no effect. CONCLUSIONS: Muscle relaxants protected the endothelium in isolated rabbit abdominal aorta from free-radical injury in a dose-dependent manner. These results suggest that vecuronium and rocuronium may act as superoxide anion scavengers.
Acetylcholine ; Antioxidants* ; Aorta ; Aorta, Abdominal ; Baths ; Catalase ; Electrolysis ; Endothelial Cells ; Endothelium ; Muscle, Smooth, Vascular ; Muscles* ; Prostaglandins ; Reactive Oxygen Species* ; Relaxation ; Superoxide Dismutase ; Superoxides ; Vecuronium Bromide

BACKGROUND: Inspired concentrations of desflurane > or = 1 minimum alveolar anesthetic concentration (MAC) have been related to sympathetic stimulation such as hypertension and tachycardia. The current study examined whether labetalol, an alpha1 and beta-adrenergic antagonist would blunt these hemodynamic responses. METHODS: Fifty-four ASA physical status I patients, aged 20-60 years, were enrolled in this study. The patients were randomly divided into 2 groups. The breathing circuit was primed with an end-tidal desflurane concentration of 1.2 MAC in 6 L/min O2. Normal saline 5 ml or labetalol 0.3 mg/kg was injected into groups S and L respectively. After 5 minutes, anesthesia was induced with intravenous etomidate 0.2 mg/kg and vecuronium 0.1 mg/kg. Each patient inhaled desflurane through a tight fitting facemask. Heart rate (HR), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP) and end-tidal concentration of desflurane (et-des) were measured at 5 minutes after saline or labetalol injection (baseline) and every 1 minute for 5 minutes after desflurane inhalation and for 2 minutes after intubation. RESULTS: In the saline injection group (group S), desflurane inhalation increased heart rate and blood pressure, while labetalol 0.3 mg/kg attenuated the heart rate and blood pressure increase in group L. After tracheal intubation, heart rate and blood pressure were significantly lower in group L than in group S. CONCLUSIONS: These results demonstrate that administration of intravenous labetalol is effective in attenuating tracheal intubation and desflurane-induced hemodynamic responses.
Aged ; Anesthesia ; Arterial Pressure ; Blood Pressure ; Etomidate ; Heart Rate ; Hemodynamics ; Humans ; Hypertension ; Inhalation ; Intubation ; Isoflurane ; Labetalol ; Respiration ; Tachycardia ; Vecuronium Bromide

Myotonic dystrophy is a rare genetic disorder characterized by muscle atrophy and weakness. Surgical treatment of this condition poses various problems for the anesthesiologist. We describe the anesthetic management of a 10-month-old infant with congenital myotonic dystrophy, who was scheduled for endoscopic third ventriculostomy under general anesthesia. Anesthesia was induced with thiopental sodium, fentanyl, and vecuronium, and thereafter maintained via continuous infusion of propofol and remifentanil. The train-of-four ratio was monitored throughout the operation, and muscle relaxation was reversed with pyridostigmine and glycopyrrolate at the end of the procedure. We show that total intravenous anesthesia using propofol and remifentanil is a satisfactory anesthetic technique in very young patients with congenital myotonic dystrophy.
Anesthesia ; Anesthesia, General ; Anesthesia, Intravenous ; Fentanyl ; Glycopyrrolate ; Humans ; Infant ; Muscle Relaxation ; Muscular Atrophy ; Myotonic Dystrophy ; Piperidines ; Propofol ; Pyridostigmine Bromide ; Thiopental ; Vecuronium Bromide ; Ventriculostomy

BACKGROUND: Corrected QT (QTc) interval can be modulated by sympathetic and parasympathetic balance. Tracheal intubation causes significant prolongation of the QTc interval due to sympathetic stimulation. This study was designed to elucidate the relationship between baseline autonomic nervous system activity and QTc prolongation after endotracheal intubation using heart rate variability (HRV). METHODS: Sixty-six healthy patients were included and the baseline HRV data were recorded for 5 min before anesthesia. Power spectrum densities were calculated for low frequencies (LF, 0.04-0.15 Hz) and high frequencies (HF, 0.15-0.4 Hz), defined as either LF's or HF's relative part of the total power. Anesthesia was induced with sevoflurane and vecuronium was given. The QTc interval, heart rate (HR) and mean arterial pressure (MAP) were measured before induction (baseline), before laryngoscopy (pre-intubation) and immediately after the intubation (post-intubation). RESULTS: The QTc interval change at post-intubation from baseline (DeltaQTc) showed a significant negative correlation with the HF (r = 0.34, P = 0.006) and positive correlation with LF/HF ratio (r = 0.37, P = 0.005). Patients were retrospectively divided into low-HF/LF (<2.5, n = 44) and high-HF/LF group (>2.5, n = 22). The DeltaQTc was statistically higher in the high-LF/HF group compared to that in the low-LF/HF group (P = 0.048). The HR and MAP at baseline, pre-intubation and post-intubation were not different between two groups. CONCLUSIONS: The QTc interval prolongation after endotracheal intubation is influenced by baseline autonomic conditions and can be exaggerated in patients with activated sympathetic activity or depressed parasympathetic activity.
Anesthesia ; Arterial Pressure ; Autonomic Nervous System ; Heart ; Heart Rate ; Humans ; Intubation ; Intubation, Intratracheal ; Laryngoscopy ; Methyl Ethers ; Retrospective Studies ; Vecuronium Bromide