Preventive Effect of Lidocaine Pretreatment and Tourniquet Use on Propofol Injection Pain / 대한마취과학회지

BACKGROUND: Pain on injection of propofol is a common problem, the cause of which remains unKnown. We evaluated the optimum time of a tourniquet with intravenous lidocaine, to decrease the intensity of pain during intravenous propofol injection. METHODS: In 72 patients undergoing general anesthesia, we subdivided all patients into 4 groups. Patients in group 1 (n = 18) received propofol only (1 mg/Kg IV) without a tourniquet, patients in group 2 (n = 18) received 1% lidocaine 20 mg IV with an upper arm tourniquet inflated to 50 mmHg applied for 1 minute followed by propofol (1 mg/Kg IV). We applied a tourniquet to patients in group 3 (n = 18) and 4 (n = 18) for 3 minutes and 5 minutes respectively. The intensity of pain along the forearm was classified in 4 degrees (none, mild, moderate, severe) by the patients and the observer simultaneously. The mean arterial pressure and heart rate were recorded before injection and at the time when the patient complained of pain. RESULTS: All groups were similar in age, sex, weight and height. The group with the tourniquet applied for 5 minutes followed by a lidocaine injection showed the lowest intensity of pain. However, between the group with 3 minutes and 5 minutes, the difference of the pain score was not statistically significant. CONCLUSIONS: We conclude that intravenous lidocaine administered after a tourniquet has been inflated to 50 mmHg for 3 minutes before propofol injection attenuates profoundly the pain associated with intravenous propofol injection.

Rocuronium and Lidocaine Pretreatment for Prevention of Biochemical Changes, Fasciculations and Myalgia following Succinylcholine Administration / 대한마취과학회지

BACKGROUND: The purpose of this study was to assess the changes in serum potassium and creatine kinase concentrations and the incidence of fasciculations and myalgia when rocuronium and lidocaine were used in combination and separately as pretreatment before succinylcholine. METHODS: We studied 60 patients undergoing a minor elective surgery, in a prospective double blinded method. Three groups each with 20 patients were pretreated before a 1.5 mg/kg succinylcholine administration with 0.05 mg/kg rocuronium three min before (group R), 1.5 mg/kg lidocaine 30 sec before (group L), or both rocuronium and lidocaine (group RL). Serum potassium and creatine kinase were respectively measured 5 min after succinylcholine administration and 24 h after the operation. Fasciculations and myalgia on postoperative day 1 and day 2 were evaluated. RESULTS: The increase in creatine kinase and incidence of myalgia on postoperative day 1 was less in the RL group than in the R group and L group. The incidence of fasciculations was higher in the L group than in the R group and RL group. There was no increase in serum potassium in any group. CONCLUSIONS: The combined use of rocuronium and lidocaine was more effective in reducing creatine kinase and postoperative myalgia than when they were used separately. However, the fasciculations were only reduced by the use of rocuronium.

Inhibitory Effects of Propofol Mixed with Lidocaine on Fentanyl Induced Cough Reflex / 대한마취과학회지

BACKGROUND: Propofol and lidocaine have been purported to attenuate bronchoconstriction induced by fentanyl administration during induction of anesthesia. The purpose of the present study was to study the synergic bronchodilation effect of propofol mixed with lidocaine. METHODS: Two hundred and thirty four patients were randomly allocated to five groups: Group 1 (n = 60, normal saline 0.25 ml/kg followed by fentanyl 3ng/kg), Group 2 (n = 30, propofol 2 mg/kg mixed with normal saline 0.05 ml/kg followed by normal saline 0.06 ml/kg), Group 3 (n = 50, propofol 2 mg/kg mixed with normal saline 0.05 ml/kg followed by fentanyl 3ng/kg), Group 4 (n = 33, propofol 2 mg/kg mixed with lidocaine 1 mg/kg followed by normal saline 0.06 ml/kg) and Group 5 (n = 61, propofol 2 mg/kg mixed with lidocaine 1 mg/kg followed by fentanyl 3ng/kg). All patients were injected with fentanyl or normal saline two minutes after administration of propofol premixed with lidocaine or normal saline, respectively. We checked the cough reflex, injection pain, oxygen desaturation and chest wall rigidity. RESULTS: There was a significant difference in the incidence of cough reflex between group 1 and 3 or 5. The incidience of group 5 was significantly lower than in group 3. CONCLUSIONS: This study suggests that a propofol-lidocaine mixture should be considered when patients require bronchodilation during induction of anesthesia.

The Effect of Preemptive Local Infiltration of Lidocaine and Gabapentin on Postoperative Pain in Rats / 대한마취과학회지

BACKGROUND: Preemptive analgesia may improve postoperative antinociceptive treatment that prevents the development of central sensitization which contributes to post-injury pain hypersensitivity. However, beneficial effects of preemptive analgesia appear controversial. The purpose of this study was to examine the effect of pre- and post-incisional local infiltration of lidocaine and gabapentin on incisional pain in rats. METHODS: Thirty five male rats were divided into 7 groups; control group (n = 5), pre-lidocaine infiltration group (n = 5), post-lidocaine infiltration group (n = 5), pre-gabapentin 10 mg infiltration group (n = 5), post-gabapentin 10 mg infiltration group (n = 5), pre-gabapentin 30 mg infiltration group (n = 5), and post-gabapentin 30 mg infiltration group (n = 5). To evaluate postoperative mechanical hyperalgesia in injured feet, withdrawal thresholds were measured by calibrated von Frey filaments at 2 hrs, 1, 2, 3, 4, and 5 days after an incision. RESULTS: The pre-lidocaine infiltration group shows better analgesic effects than post-lidocaine infiltration group until postoperative day 1 (P < 0.05). The gabapentin infiltration groups were effective in postoperative pain management but there were no significant differences between pre- and post- incisional treatment. CONCLUSIONS: A preemptive lidocaine injection has a good analgesic effect on incisional pain. Gabapentin also has a good analgesic effect on incisional pain.

The Evaluation of Topical Anesthetic Effects of a Liposome Encapsulated Mixture of Local Anesthetics (Lipo-MLA) / 대한마취과학회지

BACKGROUND: This study investigated the effect of topical analgesic effects of a liposome encapsulated mixture of local anesthetics (lipo-MLA) compared with EMLA. METHODS: 3% lipo-MLA (0.5% tetracaine base, 2.5% lidocaine base) and 5% lipo-MLA (1% tetracaine base, 4% lidocaine base) were encapsulated into liposomal vesicles made with egg yolk phosphatidylcholine, cholesterol and phosphatidyldioleoyl. 3% lipo-MLA and EMLA were applied to volunteers' forearms bilaterally with and without an occlusive dressing. The topical anesthetic effects of the lipo-MLA and EMLA as a control were evaluated by the pinprick test in 28 adult volunteers after 60 minutes of application. The analgesic influence of the concentration of local anesthetics was also compared with 3% and 5% lipo-MLA under a non-occlusive dressing. RESULTS: Analgesic effects of the 3% lipo-MLA were similar with EMLA under an occlusive dressing for 60 minutes. In addition, analgesic effects of the 3% lipo-MLA under a non-occlusive dressing were more potent than EMLA. Lipo-MLA under a non-occlusive dressing showed more potent analgesic effect than lipo-MLA under an occlusive dressing. 5% lipo-MLA was more potent than 3% lipo-MLA under a non-occlusive dressing. CONCLUSIONS: Lipo-MLA has more potent analgesic effects than EMLA without an occlusive dressing and 5% lipo-MLA is more potent than 3% lipo-MLA. Therefore, lipo-MLA appeared to be an improved topical analgesic formulation which provides a more potent and convenient topical application.

The Effects of 10% Lidocaine Spray on the Pharyngolarynx during the Endotracheal Intubation without Muscle Relaxants? / 대한마취과학회지

BACKGROUND: Tracheal intubation is usually carried out under a combination of general anesthesia and muscle relaxation. Recent sutdies have found satisfactory conditions for intubation of the trachea without using muscle relaxants. However, these studies have used large amounts of propofol or expensive opioids like alfentanil and remifentanil. In this study, we evaluated intubation conditions and success rate with midazolam, fentanyl, propofol and either 10% lidocaine applied topically into the larynx and trachea or not. METHODS: Forty patients of ASA class I or II were randomly allocated to one of two groups. All patients received glycopyrrolate 0.2 mg, midazolam 0.03 mg/kg and fentanyl 2 mcg/kg IV before induction of anesthesia and propofol 2 mg/kg IV for induction of anesthesia. Group I patients (n = 20) received 10% lidocaine into the larynx and trachea topically, and group II patients (n = 20) did not. After loss of the eyelid reflex, laryngoscopy and endotracheal intubation were attempted and airway conditions were graded. The success rate of intubation was evaluated. RESULTS: Intubation without a muscle relaxant was possible in 19 of 20 (95%) patients in group I and 8 of 20 (40%) patients in group II. There were no significant differences in scoring criteria for various airway conditions such as jaw tone, vocal cord exposure and cord position. CONCLUSIONS: Induction of anesthesia with midazolam 0.03 mg/kg, fentanyl 2 mcg/kg and propofol 2 mg/kg combined with 2 ml of 10% lidocaine spray into the larynx and trachea offered a satisfactory success rate of intubation without muscle relaxants.

Effects of Fentanyl or Clonidine on Postoperative Analgesia and Urinary Retention after Caudal Anesthesia / 대한마취과학회지

BACKGROUND: Caudal administration of local anesthetics, opioids, and the alpha2 adrenergic agonists is effective for postoperative pain. Intrathecal and epidural opioids may commonly result in urinary retention. The purpose of this study was to evaluate the effects of fentanyl or clonidine on postoperative analgesia and urinary retention. METHODS: Forty patients undergoing a hemorrhoidectomy were randomly assigned to receive 20ml of 2% lidocaine and 1 : 200,000 epinephrine plus clonidine 100 microgram (group C100, n = 10), clonidine 150 microgram (group C150, n = 10), fentanyl 50 microgram (group F50, n = 10), or fentanyl 100 microgram (group F100, n = 10) for caudal anesthesia. Mean arterial pressure (MAP) and heart rate (HR) were measured before anesthesia and immediately postanesthesia, and every 5 min after caudal administration for 30 min. The following variables were recorded: onset time, analgesic time, voiding time, and urinary retention. RESULTS: The MAP at 20, 25, and 30 min in group C150 (91 +/- 7, 91 +/- 6, and 90 +/- 7 mmHg, respectively) was less than in group F50 (99 +/- 4, 101 +/- 6, and 101 +/- 5 mmHg, respectively) (P < 0.05). There was no difference in HR and onset time of anesthesia among the groups. Analgesic times in groups C150, F50, and F100 (270 +/- 22, 265 +/- 23, and 323 +/- 82 min, respectively) were longer than in group C100 (207 +/- 59 min), (P < 0.05). The number of patients using a urinary catheter to void was much higher in group F100 (7 patients) than in the groups C100, C150, or F50 (4, 5, and 3 patients, respectively) (P < 0.05). The voiding time was longer in group C150 than in group C100 (369 +/- 122 min vs 266 +/- 83 min, P < 0.05). No side effects were reported. CONCLUSIONS: We conclude that clonidine 150 microgram is adequate to provide effective analgesia and a low incidence of urinary retention during caudal anesthesia.

A Study for Minimum Volumes of Bicarbonate to Cause Precipitation of the Domestic Lidocaines / 대한마취과학회지

BACKGROUND: When local anesthetics for regional anesthesia is used, usually small amounts of bicarbonate are added for rapid onset. This addition gives the mixed solution a more alkaline pH. The following result is an increased unionized form of the local anesthetic and rapid penetration of the drug into tissue. Unfortunately, no data about adequate mixing volumes of domestic lidocaine and bicarbonate is available. METHODS: We examined six mixing pairs of two kinds of 2% lidocaines and three kinds of 8.4% bicarbonates for minimum volumes of bicarbonate to cause a precipitation of 2% 20 ml lidocaine. RESULTS: The mean volumes of bicarbonate to cause precipitation were 1.54 ml for Kwang-Myung lidocaine with Kwang-Myung bicarbonate, 2.90 ml for Kwang-Myung lidocaine with Dae-Won bicarbonate, 2.73 ml for Kwang-Myung lidocaine with Je-Il bicarbonate, 0.97 ml for Je-Il lidocaine with Kwang-Myung bicarbonate, 1.26 ml for Je-Il lidocaine with Dae-Won bicarbonate and 1.39 ml for Je-Il lidocaine with Je-Il bicarbonate. CONCLSIONS: We conclude that the Kwang-Myung lidocaine and the Je-Il lidocaine could cause precipitation when mixing with a smaller bicarbonate volume than foreign textbook recommended.

Comparison of the Effect of Epinephrine Concentration during Caudal Epidural Anesthesia / 대한마취과학회지

BACKGROUND: The advantages of addition of epinephrine to local anesthetics during caudal epidural anesthesia are core intense block, prolonged duration of anesthesia and reduction of systemic toxic effect of local anesthetics. The currently recommended concentration of epinephrine is 1 : 200,000, but absorbed epinephrines cause unwanted hemodynamic changes, so we attempted to ascertain the minimum effective concentrations of epinephrine during caudal epidural anesthesia. METHODS: Ninty patients classified ASA physical status I or II scheduled for perianal surgery were studied. These patients were divided into four groups who received 20 ml of 2% lidocaine with epinephrine concentrations of 1 : 100,000, 1 : 200,000, 1 : 400,000 or 1 : 800,000 respectively. Before and during anesthesia, patients' mean arterial pressure (MAP) and heart rate (HR) were measured. Caudal anesthesia was performed with patients in the jack-knife position. A 3 ml test dose was administered initially and then the remaining local anesthetics were injected slowly. The onset of analgesia, duration of analgesia, and other complications were observed. RESULTS: The onset of analgesia was slowest in the 1 : 800,000 group. The duration of analgesia was longest in the 1 : 100,000 group. There were no significant difference in MAP changes, but HR increased significantly in the 1 : 100,000 group compared to the 1 : 200,00 group. There were no systemic toxic symptoms for local anesthetics except that 1 patient, who was in the 1 : 100,000 group, had symptoms of palpitation and headache, considered to be the unwanted pharmacologic effects of epinephrine. CONCLUSION: We concluded that the 1 : 400,000 epinephrine concentration can be used during caudal epidural anesthesia.

Epidural Anesthesia for Cesarean Section in a Parturient with Eisenmenger's Syndrome / 대한마취과학회지

Eisenmenger's syndrome is defined as pulmonary hypertension with right-to-left or bidirectional shunting of blood through an intracardiac or aorto-pulmonary commumication. It can occur with complex congenital cardiac malformations, such as septal defect and patent ductus arteriosus. Parturients with Eisenmenger's syndrome are at high risk for peripartum morbidity and mortality. We experienced a case of parturient for cesarean section with Eisenmenger's syndrome and performed epidural anesthesia with fractionated doses of 2% lidocaine and fentanyl. The sensory block reached to T10 level and blood pressure was maintained with intravenous phenylephrine. After baby out, sudden hypotension with severe bradycardia developed and arterial oxygen saturation dropped. Immediate intubation and resuscitation was done, but cardiac rhythm disturbance, hypoxemia, and acidosis did not corrected. Cardiac standstill developed and stopped resuscitation. The neonate's Apgar score was 7 and he was transferred to pediatric ICU.

The Local Anesthetic Effect of 10% Lidocaine Spray on the Larynx / 대한마취과학회지

BACKGROUND: Although topically applied laryngeal lidocaine is known to be effective in preventing the cardiovascular events associated with endotracheal intubation, it is still debated whether the mechanism of action of topically applied laryngeal lidocaine is via increased plasma concentration of lidocaine or via topically induced superficial anesthesia. The purpose of the present study is to observe vocal cord responses to stimulation and to find out whether topically induced superficial anesthesia with 10% lidocaine spray is effective under propofol anesthesia. METHODS: Twenty-four patients scheduled for operation on the upper or lower extremities were randomly allocated to two groups: (1) twelve patients who did not receive 10% lidocaine spray before the insertion of a laryngeal mask airway (LMA), (2) twelve patients who received 10% lidocaine spray before the insertion of LMA. The vocal cords of each patient were stimulated by the spraying of 0.2 ml distilled water or directly by bronchoscope tip, and the evoked responses were assessed by analyzing the hemodynamic and respiratory variables and vocal cord movement. The vocal cord movements elicited by the laryngeal stimulation were classified into four grades. RESULTS: There was a significant difference between the groups regarding vocal cord movement (P < 0.05). There were no differences between the groups regarding hemodynamic and respiratory variables. CONCLUSIONS: The result indicates that there is a topical anesthetic effect on the vocal cords by 10% lidocaine spray on the larynx.

The Effect of Prior Dural Puncture with a 27G Spinal Needle on Epidural Anesthesia for Cesarean Section / 대한마취과학회지

BACKGROUND: If started with segmental block, epidural anesthesia appears to have an inadequate sacral block in the early part of cesarean deliveries. A dural puncture using the combined spinal-epidural technique making an early sacral blockade might be a solution. METHODS: A prospective, randomized, double-blinded study was performed on forty patients who were divided into two groups (C, DP; n = 20, each). An epidural infusion of 25 ml of 2% lidocaine with epinephrine was given to the group C. A dural puncture with a 27G Whitacre needle was done before the epidural infusion in the group DP. Two-way sensory levels were checked for 15 min, just before the operation. The side effects and recovery variables were also compared between the groups. RESULTS: Initial wider cephalic block (P = 0.038, 0 min) followed by more caudal block (P = 0.023, 0.013; 5, 10 min after the completion of the epidural infusion, respectively) occurred in the DP group. After 10 min, there were no differences in both block levels. The number of dermatomes blocked was bigger in the DP group at 10 min after. Fewer patients in the DP group had nausea and/or vomiting (P = 0.044). CONCLUSIONS: Early spread of the sensory blockade, initial cephalic and then caudal, was due to the dural puncture by a 27G needle. This fast onset could make the parturients more comfortable in the early part of cesarean sections.

Effect of Lidocaine and Metoclopramide on Vascular Pain Associated with Intravenous Propofol Injection / 대한마취과학회지

BACKGROUND: Propofol has a high incidence of pain with intravenous injection, and different methods have been used to minimize the incidence and severity of this pain. In this study, we have compared the effect of lidocaine pretreatment with that of metoclopramide pretreatment on propofol injection pain. METHODS: Ninety healthy female patients scheduled for general anesthesia were randomly divided into three groups; saline group (n = 30), lidocaine group (n = 30) and metoclopramide groups (n = 30). Each patient received 2 ml of pretreatment solution (normal saline, 1% lidocaine, 0.5% metoclopramide) via 18 G angiocatheter inserted in the antecabital fossa after applying an arm tourniquet inflated to 50 mmHg. The tourniquet was released 1 minute later, followed by intravenous injection of 2.5 mg/kg of propofol. The assesement of pain was made at the induction of anesthesia and in the recovery room and the severity of pain was classified as none, mild, moderate, severe by one observer. RESULTS: The severity and incidence of pain diminished significantly in the lidocaine group and the metoclopramide group compared with the saline group at the induction of anesthesia (P < 0.05) and there was no significant difference between the lidocaine group and metoclopramide group. We had similar results in the recovery room and one patient from the saline group and the metoclopramide group had no recall regarding injection pain. CONCLUSIONS: Intravenous metoclopramide pretreatment is as effective as intravenous lidocaine pretreatment in alleviating the propofol injection pain.

Extension of Sensory Blockade after Thoracic and Lumbar Epidural Administration of a Test dose of Lidocaine / 대한마취과학회지

BACKGROUND: The distribution of solutions injected into the epidural space has not been well determined. The aim of this study was to compare the difference in extension of sensory blockade between the thoracic and lumbar regions in epidural analgesia. METHODS: Forty-five female patients scheduled for postoperative pain control were enrolled. In group 1 (n = 22), the Tuohy needle was inserted at T6 10 levels and in group 2 (n = 23), it was inserted at T12 L2 levels. The catheter was introduced 3 4 cm into the epidural space and 3 ml of 1.5% lidocaine with epinephrine (1:200,000) was injected. The extension of sensory anesthesia to loss of cold sensation and pinprick test was measured every 5 minute for 15 minutes. RESULTS: Fifteen minutes after epidural injection, the mean sensory block extension in group 1 (7.8 +/- 2.0 dermatomes) was significantly wider than in group 2 (4.7 +/- 2.2 dermatomes) but cranial and caudad spread of sensory blockade in relation to the puncture level was the same in both groups. CONCLUSION: The mean dose of local anesthetic required for analgesia was smaller in the thoracic region than in the lumbar region.

The Effects of Forebrain Ischemia on Lidocaine-Induced Seizure Threshold in the Rat / 대한마취과학회지

BACKGROUND: Seizures are common following many cerebral insults, include global and focal ischemia. However, while the mechanism must relate to some change in the relative activities of excitatory and inhibitory pathway, the specific alterations in neurotransmitter concentrations and/or receptor sensitivities which underlie these events, remain unknown. The principal aim of this study was therefore to evaluate the effects of moderately severe forebrain ischemia on lidocaine-induced seizure thresholds, in hopes of gaining some insights into these processes. METHODS: Halothane-anesthetized, normothermic Sprague-Dawley rats were chronically instrumented with screw electrodes and vascular catheters, and were then subjected to 10 min of forebrain ischemia, produced by bilateral carotid occlusion combined with hypotension (MAP = 30 mmHg). After reperfusion, animals were awakened. 6, 24 and 46 hours later, separate groups of awake animals were subjected to intravenous infusion of lidocaine at the rate of 2.6 mg/kg/min. The total dose of lidocaine infused prior to generalized tonic-clonic seizures were noted. Another group of Sham animals (no ischemia) served as control. RESULTS: The lidocaine-induced seizure threshold was significantly increased at 24 h after forebrain ischemia (65.39 12.9 mg/kg vs 36.47 4.24 mg/kg, P < 0.05). Interestingly, at 6 h post-ischemia, rats treated with lidocaine consistently died before seizures. There were no significant differences in seizure threshold between the control and 48 h post-ischemia groups. CONCLUSIONS: Ten minutes of forebrain ischemia is followed by a transient increase in the seizure threshold to infused lidocaine. By 48 h following reperfusion, lidocaine induced seizure threshold had returned to normal.

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.

Prolonged Regional Anesthesia with Lidocaine Microspheres by Using a Biodegradable Polymer / 대한마취과학회지

BACKGROUND: Biodegradable microspheres are a useful method of drug delivery because they are both injectable and biodegradable. Previous work in our group has characterized implantable preparations of local anesthetics in pellets for prolonged regional anesthesia. In this paper we evaluated injectable suspensions of lidocaine-polymer microspheres for extended period of percutaneous sciatic nerve blockade in rats. METHODS: Microspheres were prepared using poly (lactide-co-glycolide) loaded with 50 wt% lidocaine by a solvent evaporation method. In vitro release rate of lidocaine from microspheres was determined by high performance liquid chromatography (HPLC). Percutaneous blockade of the rat sciatic nerve was performed, and sensory blockade of the nerve was assessed using an analgesiometer. RESULTS: Lidocaine was released in a controlled manner in vitro. In general 60% of the drug released in the first day, 80% in two days. Sciatic nerve blockade duration ranged from 8 to 12 hours. Incorporation of dexamethasone 0.05 wt% into the microspheres resulted in significant prolongation of block. CONCLUSION: Prolonged percutaneous blockade of peripheral nerve is achieved using biodegradable polymeric lidocaine microspheres.

Is Muscle Relaxants Necessary during the Anesthesia for Cataract Surgery with LMA? / 대한마취과학회지

BACKGROUND: The recovery of spontaneous ventilation is delayed in elderly patients in whom muscle relaxants has been administered for general anesthesia. We evaluated the appropriateness of microscopic cataract surgery without using muscle relaxants in elderly patients. METHODS: Forty two ASA physical status I and II patients for cataract surgery were randomly assigned to two groups. Glycopyrrolate 0.2 mg, fentanyl 2 mcg/kg and propofol 2 mg/kg were administered intravenously followed by vecuronium 1 mg/kg iv in group I and 10% lidocaine 1.5 mg/kg spray into oropharynx in group II. Laryngeal mask (LMA) was inserted for airway management and anesthesia was maintained by only propofol infusion in both groups. Whether the patient moved during the surgery, whether ephedrine was administered and the propofol infusion rate were recorded. RESULTS: Six patients of group I and 1 patient of group II were moved during surgery. Only in group II, 7 patients received intravenously ephedrine administration. Mean infusion rate of propofol was 0.114 mg/kg/min in group I and 0.159 mg/kg/min in group II. CONCLUSION: In general anesthesia for microscopic cataract surgery, the combination of fentanyl 2 mcg/kg, propofol 2 mg/kg and infusion, 10% lidocaine spray and laryngeal mask without muscle relaxants is a good alternate method of keeping airway.

Is Muscle Relaxants Necessary during the Anesthesia for Cataract Surgery with LMA? / 대한마취과학회지

BACKGROUND: The recovery of spontaneous ventilation is delayed in elderly patients in whom muscle relaxants has been administered for general anesthesia. We evaluated the appropriateness of microscopic cataract surgery without using muscle relaxants in elderly patients. METHODS: Forty two ASA physical status I and II patients for cataract surgery were randomly assigned to two groups. Glycopyrrolate 0.2 mg, fentanyl 2 mcg/kg and propofol 2 mg/kg were administered intravenously followed by vecuronium 1 mg/kg iv in group I and 10% lidocaine 1.5 mg/kg spray into oropharynx in group II. Laryngeal mask (LMA) was inserted for airway management and anesthesia was maintained by only propofol infusion in both groups. Whether the patient moved during the surgery, whether ephedrine was administered and the propofol infusion rate were recorded. RESULTS: Six patients of group I and 1 patient of group II were moved during surgery. Only in group II, 7 patients received intravenously ephedrine administration. Mean infusion rate of propofol was 0.114 mg/kg/min in group I and 0.159 mg/kg/min in group II. CONCLUSION: In general anesthesia for microscopic cataract surgery, the combination of fentanyl 2 mcg/kg, propofol 2 mg/kg and infusion, 10% lidocaine spray and laryngeal mask without muscle relaxants is a good alternate method of keeping airway.

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.