Comparison of Train-of-four Response between Adductor Pollicis and Orbicularis Oculi to Determine the Optimal Time for Endotracheal Intubation after Vecuronium Administration / 대한마취과학회지

BACKGROUND: Ideal condition of endotracheal intubation after administration of non-depolarizing muscle relaxants like vecuronium is the time when the diaphragm and upper airway muscles are completely relaxed. But these muscles are difficult to determine the degree of relaxation. Neuromuscular response of these muscles are similar to that of orbicularis oculi (OO), but adductor pollicis (AP) is different. However, it is sometimes difficult to monitor OO response. The purpose of this study was to monitor the upper airway muscle relaxation using AP other than OO. METHODS: Fourty-four adult patients of ASA class 1 schaduled for elective surgery under general anesthesia were examined. Anesthesia was induced with fentanyl 2 mcg/kg, and 2 minutes later followed by thiopental sodium 5 mg/kg. After supramaximal stimulation for control twitch height, vecuronium 0.1 mg/kg was intravenously injected and applied continuous train-of-four (TOF) facial nerve stimuli. The TOF response of OO was closely observed with examiner's naked eyes. When complete relaxation of OO achieved, TOF ratio of AP and the time after vecuronium injection were recorded. Thereafter, tracheal intubation was performed and the intubating condition scores was recorded. Ulnar nerve stimuli were continuously applied until complete relaxation of AP was achieved. The time of complete relaxation of AP after vecuronium injection was also recorded. RESULTS: The onset time of complete relaxation was significantly faster in OO (181.3+/- 47.4 secs) as compared with that of AP (265.0+/-67.8 secs). The average TOF ratio of AP was 47.3+/-17.2% and the condition of intubation performed after complete relaxation of OO was satisfied. CONCLUSION: The optimal time for endotracheal intubation was about 3 min after vecuronium 0.1 mg/kg injection, when TOF ratio of AP was about 50%.

Effect of Additional Lidocaine on the Onset Time of Vecuronium / 대한마취과학회지

BACKGROUND: Local anesthetics have been shown to interact with neuromuscular blockers. Most local anesthetics decrease neuromuscular transmission and potentiate neuromuscular block from muscle relaxants. The purpose of this study was to examine the effectiveness of lidocaine on the onset time of vecuronium and to compare that with other method such as simply increasing the dose of vecuronium. METHODS: Sixty patients of ASA physical status I or II were induced with thiopental (4-5 mg/kg) and maintained with O2-enflurane (2.5 vol%). They were randomly divided into four groups: Vecuronium (0.1 mg/kg) was administered intravenously in Group C (n = 15), additional lidocaine (1 mg/kg) was given intravenously 1 min prior to administration of vecuronium in Group L (n = 15), increased vecuronium (0.15 mg/kg) was given in Group V (n = 15) and succinylcholine was given in Group S (n = 15), respectively. Neuromuscular blockade was assessed by train-of-four (TOF) at the adductor pollicis muscle with supramaximal stimulation of ulnar nerve (2 Hz, 0.2 ms) every 12 sec. Endotracheal intubation was performed and intubating conditions were evaluated according to the standard scoring method after measuring the onset time (from the end of giving each muscle relaxants to the 90% suppression of the first twitch). RESULTS: The onset time of Group L (122.0+/-11.0 sec) and that of Group V (98.0+/-16.9 sec) were shorter than that of Group C (135.2+/-16.0 sec) (P<0.05), but these were not shorter than that of Group S (42.0+/-6.2 sec). There was no statistical difference between Group L and Group V. Intubating conditions were good or excellent in all groups. CONCLUSIONS: Additional lidocaine for attenuating sympathetic response could accelerate the onset of vecuronium. But the onset time of this method was not shorter than that of simply increasing the dose of vecuroium nor that of succinylcholine.

Neuromuscular Blocking Effect of Vecuronium in Electric Burned Patients for Endotracheal Intubation / 대한마취과학회지

BACKGROUND: In inducing anesthesia for burn patients, nondepolarizing muscle relaxant (NDMR) is usually used, because succinylcholine, a widely used muscle relaxant may cause hyperkalemia. It is well known that because burn patients show resistance to NDMR, a high dose of NDMR is needed for them. In this study, we wanted to know whether there is significant difference of the relaxation effect between 0.1 mg/Kg and 0.15 mg/Kg dose's of vecuronium, and between burn and unburn patients. METHODS: Subjects are 40 male patients having 1 or 2 ASA physical status (20 are burn patients and the other 20 are unburn patients). We divided them into 4 groups; 1) Group BI (burn patients, vecuronium 0.1 mg/Kg) 2) Group BII (burn Pts, vecuronium 0.15 mg/Kg) 3) Group UBI (unburn Pts, vecuronium 0.1 mg/Kg) 4) Group UBII (unburn Pts, vecuronium 0.15 mg/Kg). Average onset times (time from injection of vecuronium to zero first twitch height (T1)) were measured and intubating condition were scored on 0 to 4 scale. RESULTS: The onset time of vecuronium and distribution of intubation scores didn't show statistical differences among 4 groups. CONCLUSION: The onset time of vecuronium and intubating condition in burn patients dosen't show a difference from unburn patient.

The Effect of Vecuronium-Lidocaine Mixture Administration on the Onset of the Neuromuscular Block of Vecuronium / 대한마취과학회지

BACKGROUND: For the rapid sequence induction of general anesthesia, succinylcholne, a depolarizing muscle relaxant, has been used. But succinylcholine has many side effects, so various efforts using nondepolarizing muscle relaxants have been tried. We have tried and observed the effect of a curonium-lidocaine mixture administration. METHODS: 120 patients who were scheduled for elective surgery were randomly assigned in 6 groups (Group I, II, III, IL, IIL, IIIL). For groups I, II and III vecuronium was administered only 0.10 mg/kg, 0.12 mg/kg, and 0.15 mg/kg, respectively. For each member of groups IL, IIL and IIIL, lidocaine 1.5 mg/kg was added to the dose of vecuronium of groupI, II and III. The vecuronium or vecuronium- lidocaine mixture was injected for 15 seconds and then thiopental sodium was injected for 15 seconds. 90 seconds after the administration of the vecuronium or vecuronium-lidocaine mixture, every patient was intubated. Intubation condition scores, TOF responses of the adductor pollicis of the thumb, arrhythmia, heart rates, systolic blood pressure, diastolic blood pressure and mean arterial blood pressure were checked and compared. RESULTS: Intubation condition scores were better in groups IL, IIL and IIIL in comparison with groups I, II and III. The TOF responce of the adductor pollicis of the thumb showed a statistically signifiant difference between the lidocaine groups and the nonlidiocaine groups. The time elapsed before the disappearance of TOF was less in the lidocaine groups. Changes of systolic pressure, diastolic pressure, mean arterial blood pressure and heart rate were no difference in the lidocaine groups and the nonlidocaine groups. CONCULUSIONS: The results suggest that administration of a vecuronium-lidocaine mixture administraion improves the intubation condition score during a rapid sequence induction of general anesthesia and shortens the time of the disapprearance of the TOF response.

The Effect of Vecuronium-Lidocaine Mixture Administration on the Onset of the Neuromuscular Block of Vecuronium / 대한마취과학회지

BACKGROUND: For the rapid sequence induction of general anesthesia, succinylcholne, a depolarizing muscle relaxant, has been used. But succinylcholine has many side effects, so various efforts using nondepolarizing muscle relaxants have been tried. We have tried and observed the effect of a curonium-lidocaine mixture administration. METHODS: 120 patients who were scheduled for elective surgery were randomly assigned in 6 groups (Group I, II, III, IL, IIL, IIIL). For groups I, II and III vecuronium was administered only 0.10 mg/kg, 0.12 mg/kg, and 0.15 mg/kg, respectively. For each member of groups IL, IIL and IIIL, lidocaine 1.5 mg/kg was added to the dose of vecuronium of groupI, II and III. The vecuronium or vecuronium- lidocaine mixture was injected for 15 seconds and then thiopental sodium was injected for 15 seconds. 90 seconds after the administration of the vecuronium or vecuronium-lidocaine mixture, every patient was intubated. Intubation condition scores, TOF responses of the adductor pollicis of the thumb, arrhythmia, heart rates, systolic blood pressure, diastolic blood pressure and mean arterial blood pressure were checked and compared. RESULTS: Intubation condition scores were better in groups IL, IIL and IIIL in comparison with groups I, II and III. The TOF responce of the adductor pollicis of the thumb showed a statistically signifiant difference between the lidocaine groups and the nonlidiocaine groups. The time elapsed before the disappearance of TOF was less in the lidocaine groups. Changes of systolic pressure, diastolic pressure, mean arterial blood pressure and heart rate were no difference in the lidocaine groups and the nonlidocaine groups. CONCULUSIONS: The results suggest that administration of a vecuronium-lidocaine mixture administraion improves the intubation condition score during a rapid sequence induction of general anesthesia and shortens the time of the disapprearance of the TOF response.

Influence of Propofol and Enflurane on the Neuromuscular Effects of Vecuronium / 대한마취과학회지

BACKGROUND: Previous studies reported the lack of interaction between propofol and neuromuscular blockers. The current study was designed to compare the influence of propofol to that of enflurane on the vecuronium. METHODS: Forty , either sex, adult patients, scheduled for elective surgery, were randomly assigned to two groups. Patients received either propofol (Group I n=20) or thiopental (Group II n=20) as an induction agent and anesthesia were maintained with either propofol-N2O-O2(Group I) or enflurane- N2O-O2(Group II). Before induction, initial twitch was obtained as a control with supramaximal stimulus. Neuromuscular contraction was monitored continuously and recorded on a relaxograph. Onset time (T0), clinical duration (T25), and recovery index (RI) were measured. RESULTS: Onset time and clinical duration of vecuronium were not significantly different between two groups. Mean recovery index was 18.5 min and 38.6 min in group Iand II, respectively. CONCLUSION: These results indicated that propofol, different from enflurane, did not have influence on the recovery index of vecuronium.

The Relationships between Administration Time of Pyridostigmine and the Recovery of Vecuronium-induced Neuromuscular Blockade / 대한마취과학회지

BACKGROUND: The timing of administration may be an important factor in order to obtain maximal antagonizing effect of anticholinesterase on neuromuscular blockade. The objective of this study is to seek for the optimal administration time of pyridostigmine for reducing the recovery time of vecuronium. METHODS:Thirty patients were devided into three groups,who were receiving intravenously pyridostigmine (0.2 mg/kg) at 10% (group 1), 20% (group 2) and 25% (group 3) recovery of T1. The recovery indices (RI: time taken for T1 to recover from 25 to 75% of control) and recovery time (time taken for T1 to recover from 5% to 20, 25, 50 & 75%) in vecuronium (0.1 mg/kg) neuromuscular blockade were checked and compared between 3 groups using train of four stimulation with Relaxograph(Datex co., Finland). RESULTS: The recovery time (T5-20, T5-25, T5-50, T5-75) was significantly faster in the group 1 than the group 3. But there were no significant differences in recovery indices (RI) between 3 groups. CONCLUSIONS: Provided there is a slightest evidence of spontaneous recovery, early administration of anticholinesterse will reduce the recovery time of nondepolarizing neuromuscular block. But it can not affect the dissociation rate of vecuronium (KD) and there were no significant differences in recovery indices.