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Rationale: Extracorporeal membrane oxygenation (ECMO) in multiple trauma patients with post-traumatic respiratory failure can be quite challenging because of the need for systemic anticoagulation, which may lead to excessive bleeding. In the last decade, there is a growing body of evidence that veno-venous ECMO (VV-ECMO) is lifesaving in multiple trauma patients with acute respiratory distress syndrome, thanks to technical improvements in ECMO devices. Patient concerns: We report a case of a 17-year-old multiple trauma patient who was drunken and had confused mentality. Diagnoses: She was suffered from critical respiratory failure (life-threatening hypoxemia and severe hypercapnia/acidosis lasting for 70 minutes) accompanied by cardiac arrest and trauma-induced coagulopathy during general anesthesia. Interventions: We decided to start heparin-free VV-ECMO after cardiac arrest considering risk of hemorrhage. Outcomes: She survived with no neurologic sequelae after immediate treatment with heparin-free VV-ECMO. Lessons: Heparin-free VV-ECMO can be used as a resuscitative therapy in multiple trauma patients with critical respiratory failure accompanied by coagulopathy. Even in cases in which life-threatening hypoxemia and severe hypercapnia/acidosis last for >1 hours during CPR for cardiac arrest, VV-ECMO could be considered a potential lifesaving treatment.

Background: The combined induction using two or more agents has a potential benefit that anesthesia could be induced with smaller anesthetic agents with fewer side effects. We studied the effects of co-administration with midazolam and remifentanil on the dose of propofol, the time to loss of consciousness (LOC) and hemodynamics during tracheal intubation. Methods: Sixty patients were randomly assigned to three groups. Group 1 was induced with target-controlled propofol alone. Group 2 received midazolam (0.05 mg/kg) and target-controlled propofol. Group 3 received midazolam (0.025 mg/kg), remifentanil (2 ng/ml) and target-controlled propofol. The time to LOC, the infused propofol dose and the effect site concentration at LOC were recorded. After LOC, rocuronium (0.6 mg/kg) was given and tracheal intubation was performed. The noninvasive blood pressure, heart rate (HR) and bispectral index were recorded. Results: The time and the dose of propofol to LOC were significantly reduced in group 2, 3 than in group 1 (P ＜ 0.05). Compared with pre-induction values, mean blood pressure at immediately after intubation was increased in group 1, 2 with no change in group 3. The HR immediately after intubation was significantly increased in all groups compared to the pre-induction values, but the rate of increase of HR in group 3 were significantly lower than those group 1, 2 (P ＜ 0.05). Conclusions: The co-administration with midazolam and remifentanil reduces the time to LOC and the dose of propofol. That also attenuates hemodynamics during tracheal intubation under target-controlled infusion of propofol. (Korean J Anesthesiol 2009; 56: 619～23)

Background/Aims Sedative use is common in endoscopic examinations. The anxiety regarding sedative use may be different between doctors and nonmedical individuals. Methods A questionnaire survey was conducted by a research company (DOOIT Survey), and responses were collected from 649 doctors and 1,738 individuals who perform typical jobs in nonmedical fields. In this study, these ordinary workers are considered to represent nonmedical individuals. Anxiety was measured using a 5-point Likert scale. Results The nonmedical individuals exhibited more anxiety regarding the sedative use than the doctors. Age

Background: The ability to explore the anatomy has improved our appreciation of the brachial anatomy and the quality of regional anesthesia. Using real-time ultrasonography, we investigated the cross-sectional anatomy of the brachial plexus and of vessels at the axillary fossa in Koreans. Methods: One hundred and thirty-one patients scheduled to undergo surgery in the region below the elbow were enrolled after giving their informed written consent. Using the 5 -12 MHz linear probe of an ultrasound system, we examined cross-sectional images of the brachial plexus in the supine position with the arm abducted by 90 o , the shoulder externally rotated, and the forearm flexed by 90 o at the axillary fossa. The results of the nerve positions were expressed on a 12-section pie chart and the numbers of arteries and veins were reported. Results: Applying gentle pressure to prevent vein collapse, the positions of the nerves changed easily and showed a clockwise order around the axillary artery (AA). The most frequent positions were observed in the 10 -11 section (79.2%) for the median, 1-2 section (79.3%) for the ulnar, 3-5 section (78.4%) for the radial, and 8-9 section (86.9%) for the musculocutaneous nerve. We also noted anatomical variations consisting of double arteries (9.2%) and multiple axillary veins (87%). Conclusions: Using real-time ultrasonography, we found that the anatomical pattern of the major nerves in Koreans was about 80% of the frequent position of individual nerves, 90.8% of the single AA, and 87% of multiple veins around the AA. (Korean J Anesthesiol 2014; 67: 310-316)

This paper presents an observer to estimate the displacement of hydraulic cylinders of an underwater robot for harbour construction using a pressure sensor. In harbour constructing, we place heavy armour stones weighing over 2~3 tons on the surface of the bank to protect it from storming wave. This work typically done by a diver is difficult and dangerous so that we have developed Stone Diver which is the underwater robot for harbour construction. The robot needs a displacement sensors to control the position of hydraulic cylinders. The position sensors mounted outside the cylinders cause poor durability in construction site where shock and dust usually occur. However, the pressure sensor mounted inside a waterproof box improves the durability. Based on the dynamic parameters and the pressures in the cylinder, the observer estimates the cylinder`s position. This paper presents the positional accuracy of the pressure based observer and the performance of the underwater robot to assemble the armour stones.

Sacral insufficiency fracture resulting from a metastatic tumor or an osteoporotic fracture causes severe low back pain and radiating pain mass effect on neural foramen and chemical irritants. Percutaneous sacroplasty is one of the effective treatment modalities for sacral insufficiency fracture and its pain. Because of the structural complexity of the sacrum, obtaining an epidurogram of the S1 and S2 nerve roots before the start of the procedure can be helpful to avoid nerve injury. We present 2 successful cases of percutaneous sacroplasty performed under fluoroscopic guidance. A 65-year-old man with sacral metastasis from stomach cancer and a 52-year-old man with sacral insufficiency fracture were suffering from severe buttock pain and radiating pain. After epidurography of the S1 and S2 nerve roots with steroid and contrast dye, percutaneous sacroplasty with fluoroscopy on the S1 or S2 body and alae was performed on both patients. There was no cement leakage or any other major complications. Both patients experienced significant reduction in pain.

Background: Benzodiazepines have a hypnotic/sedative effect through the inhibitory action of γ-aminobutyric acid type A receptor. Flumazenil antagonizes these effects via competitive inhibition, so it has been used to reverse the effect of benzodiazepines. Recently, flumazenil has been reported to expedite recovery from propofol/remifentanil and sevoflurane/remifentanil anesthesia without benzodiazepines. Endogenous benzodiazepine ligands (endozepines) were isolated in several tissues of individuals who had not received benzodiazepines. Methods: Forty-five healthy unpremedicated patients were randomly allocated to either flumazenil or a control groups. Each patient received either a single dose of 0.3 mg of flumazenil (n = 24) or placebo (n = 21). After drug administration, various recovery parameters and bispectral index (BIS) values in the flumazenil and control groups were compared. Results: Mean time to spontaneous respiration, eye opening on verbal command, hand squeezing on verbal command, extubation and time to date of birth recollection were significantly shorter in the flumazenil group than in the control group (P = 0.004, 0.007, 0.005, 0.042, and 0.016, respectively). The BIS value was significantly higher in flumazenil group than in the control group beginning 6 min after flumazenil administration. Conclusions: Administration of a single dose of 0.3 mg of flumazenil to healthy, unpremedicated patients at the end of sevoflurane/fentanyl anesthesia without benzodiazepines resulted in earlier emergence from anesthesia and an increase in the BIS value. This may indicate that flumazenil could have an antagonistic effect on sevoflurane or an analeptic effect through endozepine-dependent mechanisms. (Korean J Anesthesiol 2012; 62: 19-23)

In this study, we develop a pressure observer to measure the cylinder length of a harbor-construction robot. For the robot control, sensors are required to measure the length of a hydraulic cylinder. The cylinder-position sensor is relatively expensive when the operating environment prohibits external approaches for the measurement of the cylinder position. LVDT or linear scales are usually mounted on the outside of the cylinder, which causes poor durability on a construction site. We use a pressure sensor to indirectly estimate the length of the cylinder. The pressure sensor is mounted inside a hydraulic valve box so that it is protected by the box and easy to waterproof for an underwater robot. By treating oil as a compressible fluid, we derive the nonlinear pressure dynamics as a function of the cylinder position, velocity, and pressure. The recursive least squares (RLS) algorithm is applied to identify the dynamic parameters, and the pressure observer estimates the cylinder position through the pressure acting on the head and the rod of the hydraulic cylinder. The position accuracy is relatively low, but it is acceptable for a construction robot that handles large armor stones.

Background: Postoperative ipsilateral shoulder pain occurs in 37% to 68% of patients undergoing a thoracotomy. We examined whether interscalene brachial plexus block using a lower concentration of local anesthetic would reduce the incidence of post-thoracotomy ipsilateral shoulder pain with assessment of pulmonary function in patients who underwent a lung lobectomy. Methods: Forty-four patients who underwent a lung lobectomy were randomly assigned to either the control or the interscalene block group. Single-shot interscalene block on the surgical site side was performed using ropivacaine 0.25% 10 mL including dexamethasone 5 mg under ultrasound guidance in the interscalene block group. Lobectomy and continuous paravertebral block were performed under general anesthesia. The presence of ipsilateral shoulder pain and postoperative adverse events were assessed. Pulmonary function tests were performed preoperatively, the day after surgery, and the day after removing the chest tube. Results: The incidence of ipsilateral shoulder pain was significantly lower in the interscalene block group than in the control group (54.5% vs 14.3%, P = .006) with an overall incidence of 34.9%. Postoperative adverse events were similar between the groups, with no patients presenting symptoms of respiratory difficulty. Significant reductions in pulmonary function were observed in all patients after lobectomy; however, no significant difference in any of the pulmonary function test variables was observed postoperatively between the groups. Conclusions: Interscalene block using 10 mL of 0.25% ropivacaine including dexamethasone 5 mg reduced the incidence of post-thoracotomy ipsilateral shoulder pain and did not result in additional impairment of pulmonary function.

We have been developing an underwater robot for harbour construction using a parallel mechanism The robot is attached to the rope of a crane, which curries a large stone into the undersea The robot`s yaw and pitch are controlled by hydraulic cylinders but its roll is uncontrollable. We mount propellers in both side of the robot to generate the roll motion This paper studies on the control for the roll motion of a underwater robot. A gyro-sensor is used to measure the angle in a roll motion We develop the dynamic model to describe the robot`s roll motion by a second order non-linear system and identify the model parameters by recursive least square and adaptive identifier. PD control, recursive model based control and adaptive model based control are applied with the dynamic model which computes the control input to compensate disturbances. This paper introduces the underwater robot system and presents the simulated and experimental results of the proposed controller.

This paper presents a parallel typed walking robot to improve walking space and stability region. The robot is designed by inserting an intermediate mechanism between upper leg mechanism and lower leg mechanism. The leg mechanism is composed of three legs and base, which form a parallel mechanism with ground. Seven different types of walking robot are invented by combining the leg mechanisms and an intermediate mechanism. Topology is applied to design the leg mechanism. A motor vector is adopted to determine Jacobian and a wrench vector is used to analyze dynamics of the robot. We explore the stability region of the robot from the reaction force of legs and compute ZMP including the holding force to contact the foot to a wall. This investigates a walking stability when the robot walks on the ground as well as on the wall. We examine the walking space generated by support legs and by swing legs. The robot has both a large positional walking space and a large orientational walking space so that it can climb from a floor up to a wall.

This paper designs a four legged parallel walking robot to go through a narrow hole. Topology design is conducted for a leg mechanism composed of four legs, base and ground, which constitute a redundant parallel mechanism. This mechanism is subdivided into four sub-mechanism composed of three legs. A motor vector is adopted to determine the 6×8 Jacobian of the redundant parallel mechanism and the 6×6 Jacobian of the sub-mechanisms, respectively. The condition number of the Jacobian matrix is used as an index to measure a dexterity. We analyze the condition numbers of the Jacobian over the positional and orientational walking space. The analysis shows that a sub-mechanism has lots of singularities within workspace but they are removed by a redundant parallel mechanism improving a dexterity. From the results, we can propose a parallel typed walking robot to enlarge walking space and stability region. The robot is designed by inserting an intermediate mechanism between upper and lower leg mechanisms. The robot is reasonably small so that it can go through a narrow hole.

BACKGROUND: The analgesic interaction between cannabinoids and local anesthetics has not been investigated. We sought to determine the nature of the interaction between the intrathecal cannabinoid receptor agonist (WIN 55,212-2) and bupivacaine using the formalin test. METHODS: Lumbar intrathecal catheters were implanted in male Sprague-Dawley rats. After intrathecal administration of WIN 55,212-2, bupivacaine, or their combination, 50 μL of 5% formalin was injected subcutaneously into the hindpaw. Dose-response curves were established and the respective ED 50 (50% effective dose) values were determined for each agent alone. Fixed-ratio combinations of WIN 55,212-2 and bupivacaine were tested for combined antinociceptive effects in the formalin test and an isobolographic analysis was performed to characterize the pharmacologic interaction of both drugs. RESULTS: Intrathecally administered WIN 55,212-2, bupivacaine, or their combination produced a dose-dependent decrease in the number of flinches during Phase 1 and 2 of the formalin test. Isobolographic analysis revealed a synergistic interaction between intrathecal WIN 55,212-2 and bupivacaine in both phases of the formalin test. In combination, the ED 50 value was significantly smaller than the theoretical additive value (P < 0.05). CONCLUSIONS: These results demonstrate that intrathecally coadministered WIN 55,212-2 and bupivacaine provide synergistic antinociceptive interaction in both phases of the formalin test.

Gabapentin, a derivative of γ-aminobutyric acid (GABA), is used to treat epilepsy and neuropathic pain. The pharmacological mechanisms for gabapentin effects are not completely elucidated. We investigated the effect of gabapentin on the activity of excitatory amino acid transporter 3 (EAAT3) that can regulate extracellular glutamate concentrations. EAAT3 was expressed in Xenopus oocytes. Membrane currents were recorded after application of l-glutamate in the presence or absence of different concentrations of gabapentin (1-300μM) by using a two-electrode voltage clamp. To determine the effect of gabapentin on Vmax and Km of EAAT3 for l-glutamate, l-glutamate at 3-300μM was used. To study the effects of protein kinase C (PKC) and phosphatidylinositol 3-kinase (PI3K) on gabapentin-induced changes in EAAT3 activity, oocytes were incubated with the PKC activator (Phorbol 12-myristate 13-acetate, PMA), the PKC inhibitors (chelerythrine or staurosporine), and the PI3K inhibitor wortmannin. Gabapentin decreased EAAT3 activity in a concentration-dependent manner and EAAT3 activity was significantly inhibited by 10-300μM gabapentin. Gabapentin significantly decreased Vmax without affecting Km. PMA increased EAAT3 activity; however, gabapentin attenuated the PMA-induced increase in EAAT3 activity. Pre-incubation of oocytes with chelerythrine, staurosporine, or wortmannin decreased basal EAAT3 activity, which was further reduced by gabapentin. We conclude that gabapentin decreases EAAT3 activity at clinically relevant and higher concentrations, in which PKC and PI3K may not be involved. The results suggest that EAAT3 might not be a target for the anticonvulsant action of gabapentin.

Pine needle-based products are popular dietary supplements in East Asia for health promotion. Pine needle extract (PNE) are especially known as potential anti-hypertensive and anti-lipidemic agents. We report a case of profound, long-lasting unexplained hypotension during and after anesthesia in a patient treated with PNE. Bedside transthorasic echocardiography (TTE) was used as a part of useful diagnostic modality.

This research develops two types of heavy robots to cover breakwater with armour stones. The robots assemble the armour stones weighing over two tons on the surface of the breakwater to protect it from storming waves. For construction above sea level, a robot named Stone Man is developed, whereas for construction below sea level, a robot named Stone Diver is built. In addition, Underwater Filming Device (UFD) is designed to film objects in turbid water. Stone Man is designed by a parallel mechanism which enables to handle heavy armour stones dexterously. Stone Diver is developed to work in subsea by waterproofing Stone Man. UFD films objects through the clean water in a transparent box. Stone Diver works with UFD to assemble armour stones in turbid water. Its efficiency depends on the operator’s skill but Stone Diver is expected to have much higher efficiency in deep water where human divers are unable to work. Furthermore, while the work is being carried out, UFD is capturing a live video of working process which is recorded for supervisory data so that the work quality can be easily managed.

Bilateral vocal cord palsy (BVCP) is a rare complication of thyroid surgery, and it is confusing and frustrating for both patients and medical staff....

Background: The purpose of this study was to evaluate the effect of the addition of 5 mg dexamethasone to 10 ml of 0.5% levobupivacaine on postoperative analgesic effects of ultrasound guided-interscalene brachial plexus block (ISBPB) in arthroscopic shoulder surgery under general anesthesia. Methods: In 60 patients scheduled for arthroscopic shoulder surgery that underwent general anesthesia, ISBPB was preoperatively performed with 10 ml of 0.5% levobupivacaine under the guidance of ultrasound and a nerve stimulator. Patients were randomly allocated to receive the same volume of normal saline (Group I), 5 mg of dexamethasone (Group II), or 1 : 400,000 epinephrine (Group III) as an adjuvant to the mixture. A blind observer recorded total analgesic consumption, sleep quality, complication, and patient satisfaction using a verbal numerical rating scale (VNRS) at 0, 1, 6, 12, 24, 48 h after the operation. Results: All patients had successful ISBPB and excellent analgesic effects less than VNRS 4 up to discharge time. VNRS in Group II at 12 h and 48 h was statistically much lower than in Group I and III. There were no differences in total analgesic consumption, sleep quality, complications, and patient satisfaction. Conclusions: We conclude that the addition of 5 mg of dexamethasone to 10 ml of 0.5% levobupivacaine in ISBPB showed improvement of postoperative analgesia for arthroscopic shoulder operation without any specific complications. (Korean J Anesthesiol 2012; 62: 130-134)

Fat embolism syndrome is a rare and potentially lethal complication most commonly seen in long bone fractures and intramedullary manipulation. The clinical triad of fat embolism syndrome consists of mental confusion, respiratory distress, and petechiae. This study reports a case of cerebral fat embolism syndrome following elective bilateral total knee replacement. After an uneventful anesthesia and initial recovery, the patient developed neurologic symptoms nine hours postoperatively.

This paper designs a four legged parallel mechanism to improve the dexterity of three layered parallel walking robot. Topology design is conducted for a leg mechanism composed of four legs, base and ground, which constitute a redundant parallel mechanism. This mechanism is subdivided into four sub-mechanism composed of three legs. A motor vector is adopted to determine the 6×8 Jacobian of the redundant parallel mechanism and the 6×6 Jacobian of the sub-mechanisms, respectively. The condition number of the Jacobian matrix is used as an index to measure a dexterity. We analyze the condition numbers of the Jacobian over the positional and orientational walking space. The analytical results show that a sub-mechanism has lots of singularities within workspace but they are removed by a redundant parallel mechanism improving the dexterity. This paper presents a parallel typed walking robot to enlarge walking space and stability region. Seven types of three layered walking robots are designed by inserting an intermediate mechanism between the upper and the lower legged parallel mechanisms. They provide various types of gaits to walk rough terrain and climb over a wall with small degrees of freedom.Copyright © 2009 by ASME

To determine if fentanyl-induced cough was dose-dependent in children and whether it could affect tracheal intubation.Prospective, randomized, double-blinded study.Operating room of a university-affiliated hospital.160 ASA physical status I pediatric patients, aged two to 14 years, scheduled for elective surgery during general anesthesia and requiring orotracheal intubation.Patients were divided into two groups. Group 1 patients were given fentanyl at a dosage of one microg/kg; Group 2 patients received two microg/kg of fentanyl. Induction of anesthesia was conducted immediately following cough cessation or one minute after the end of injection with propofol 2.5 mg/kg. At loss of eyelash reflex, rocuronium 0.6 mg/kg was given intravenously (IV). Two minutes later, tracheal intubation was started.Onset and degree of cough and intubating conditions were observed and recorded.No statistically significant differences in frequency of coughing or in intubating conditions between the two groups were noted. Cough severity in Group 1 was statistically lower than that of Group 2 (P0.05). Onset of cough in Group 2 (12.2 +/- 3.4 sec) was statistically shorter than in Group 1 (16.9 +/- 7.6 sec, P0.05).Fentanyl at doses of one and two microg/kg may induce coughing in pediatric patients.

This research studies on topological design the robot manipulator combined a 3-DOF parallel manipulator and a 2-DOF wrist manipulator (PMWM). The robot has a parallel manipulator with three links and a central link for positional motions, i.e., x, y, and z and a wrist manipulator with two rotary active joints for rotational motions, i.e., yaw and pitch. The proposed parallel-serial typed manipulator is applied to machining and assembly works for the complex shape. These works must meet between high stiffness and large workspace of the manipulator. In order to achieve the topological design on workspace of a 2-DOF wrist manipulator, we adopt the degree of parallelism and define the d.o.f of a link and the radius of a base and a platform, the initial length of link, etc. To determine the parameters of wrist, investigation is done i.e., kinematics and workspace analysis. In results, we show topological design parameters of the manipulator meet a desired workspace.

Several factors can affect the perioperative immune function. We evaluated the effect of propofol and desflurane anesthesia on the surgery-induced immune perturbation in patients undergoing breast cancer surgery. The patients were randomly assigned to receive propofol (n = 20) or desflurane (n = 20) anesthesia. The total and differential white blood cell counts were determined with lymphocyte subpopulations before and 1 hr after anesthesia induction and at 24 hr postoperatively. Plasma concentrations of interleukin (IL)-2 and IL-4 were also measured. Both propofol and desflurane anesthesia preserved the IL-2/IL-4 and CD4+/CD8+ T cell ratio. Leukocytes were lower in the propofol group than in the desflurane group at 1 hr after induction (median [quartiles], 4.98 [3.87-6.31] vs. 5.84 [5.18-7.94] 103/µL) and 24 hr postoperatively (6.92 [5.54-6.86] vs. 7.62 [6.22-9.21] 103/µL). NK cells significantly decreased 1 hr after induction in the propofol group (0.41 [0.34-0.53] to 0.25 [0.21-0.33] 103/µL), but not in the desflurane group (0.33 [0.29-0.48] to 0.38 [0.30-0.56] 103/µL). Our findings indicate that both propofol and desflurane anesthesia for breast cancer surgery induce a favorable immune response in terms of preservation of IL-2/IL-4 and CD4+/CD8+ T cell ratio in the perioperative period. With respect to leukocytes and NK cells, desflurane anesthesia is associated with less adverse immune responses than propofol anesthesia during surgery for breast cancer. (Clinical trial registration at https://cris.nih.go.kr/cris number: KCT0000939) Graphical Abstract

This paper presents an underwater robot developed for harbor construction, which requires the robot to carry a heavy load with large workspace and high dexterity. The requirement can't be attained by a conventional serial typed robot but by a parallel typed robot. For underwater work, it is necessary to waterproof the robot and its sensors. Especially, a sensor waterproof is a main drawback to build the underwater robot. This leads us to develop a sensorless observer which gives the position information without any position sensor. We design a neural network to identify the displacement change of the hydraulic cylinder according to the voltage exerting at servo valve. This paper introduces the design strategy for the parallel typed robot and the development with hydraulic control and wireless communication. The robot is attached to the end of an excavator or a crane to carry a large stone to build a bank. This paper shows the experimental results and explains the performance of the robot.

Vasovagal syncope (neurocardiogenic syncope) is considered the most common cause of repetitive syncope [1]. Severe pain, emotional stress, anxiety, erect postural change in a patient who is in a hypovolemic state, invasive medical procedures such as intravenous catheter insertion, venipuncture and neuraxial anesthesia are regarded as triggering factors for this syndrome. Additionally, the resulting sympathetic tone increase and the positive inotropic state that result from the aforementioned triggers are considered potent vagal reflex responses leading to sympathetic inhibition, bradycardia, acute drop in blood pressure and ensuing syncope and circulatory collapse [2]. Generally, these conditions resolve spontaneously or treated with conservative methods, such as volume replacement, without any significant sequelae [2,3]. In this case report, the suspected vasovagal syncope that developed immediately after the transcutaneous fine-needle aspiration biopsy of the right lung nodule did not respond to the conservative therapy and abruptly progressed to fatal cardiovascular collapse with cardiac arrest, and resulted in cerebrovascular accident (CVA). Five weeks after the event, when the patient’s neurological state was stabilized, the elective lung lobectomy was performed after prophylactic pacemaker insertion and was completed safely. Herein, we report this case experience and review the literature, followed by a discussion.

Polyuria is occasionally observed during general anesthesia. Usually urine output during general anesthesia is decreased because of anesthetic agents. The authors came across with a case of polyruia during sevoflurane anesthesia which occurred after induction of anesthesia. Polyuria is a nonspecific symptom, but can cause many serious complications. Therefore, it is very important to investigate the cause thoroughly and treat patient appropriately. (Ewha Med J 2013;36(1):72-76)

Background: In an axillary brachial plexus block (ABPB), where relatively large doses of local anesthetics are administered, levobupivacaine is preferred due to a greater margin of safety. However, the efficacy of levobupivacaine in ABPB has not been studied much. We performed a prospective, double-blinded study to compare the clinical effect of 0.375% levobupivacaine with 0.5% levobupivacaine for ultrasound (US)-guided ABPB with nerve stimulation. Methods: Forty patients undergoing elective upper limb surgery were randomized into two groups: Group I (0.375% levobupivacaine) and Group II (0.5% levobupivacaine). All four main terminal nerves of the brachial plexus were blocked separately with 7 ml of levobupivacaine using US guidance with nerve stimulation according to study group. A blinded observer recorded the onset time for sensory and motor block, elapsed time to be ready for surgery, recovery time for sensory and motor block, quality of anesthesia, patient satisfaction and complications. Results: There were no significant differences in the time to find nerve locations, time to perform block and number of skin punctures between groups. Insufficient block was reported in one patient of Group I, but no failed block was reported in either group. There were no differences in the onset time for sensory and motor block, elapsed time to be ready for surgery, patient satisfaction and complications. Conclusions: 0.375% levobupivacaine produced adequate anesthesia for ABPB using US guidance with nerve stimulation, without any clinically significant differences compared to 0.5% levobupivacaine. (Korean J Anesthesiol 2012; 62: 24-29)

Background: Ultrasound guided-interscalene brachial plexus block (US-ISBPB) becomes more popular and has higher success rate. The aim of this study was to assess the analgesic effectiveness of US-ISBPB with low dose levobupivacaine for arthroscopic shoulder surgery. Methods: The thirty patients undergoing elective arthroscopic shoulder surgery were randomly assigned to two groups: Group B0.5, and Group B0.25 received ultrasound-guided ISBPB using same volume 10 ml of 0.5% levobupivacaine and 0.25% levobupivacaine, respectively. General anesthesia was standardized. All patients received continuous intra-articular infusion of a local anesthetic. Remifentanil consumption during operation, verbal numerical rating scales (VNRS) after operation were assessed. The need for rescue analgesics in post-anesthesia care unit (PACU), sleep quality, and complications were documented. Results: There were no significant differences in VNRS at 20 min, 30 min, 60 min, 120 min, 8 h, 24 h after surgery, remifentanil consumption during operation, the number of patients required rescue analgesics in the PACU, sleep quality, and complication up to 24 h after surgery. Conclusions: Ultrasound-guided interscalene brachial plexus block with levobupivacaine, 10 ml of 0.5% and 0.25%, provides effective analgesia after arthroscopic shoulder surgery. (Korean J Anesthesiol 2009; 57: 302∼7)

Background: Both ketorolac and propacetamol are used postoperatively to control mild to moderate pain. This study compared the analgesic efficacy of ketorolac and propacetamol delivered either preoperatively or postoperatively, and assessed the preemptive analgesic effect of ketorolac and propacetamol for adenotonsillectomy. Methods: One hundred and two pediatric patients were divided randomly into four groups. The K1 and P1 groups received ketorolac 1 mg/kg or propacetamol 30 mg/kg after induction, respectively, whereas the K2 and P2 groups received each drug at the end of the operation, respectively. After adenotonsillectomy, we measured the NRS (Numerical Rating Scale), FPS (Faces Pain Scale) and OPS (Objective Pain scale) at 15, 30 and 60 min after arriving at the postanesthesia care unit. Results: There were no significant differences in the NRS, FPS and OPS between K1 and K2 and between P1 and P2 for 60 min after operation at the postanesthesia care unit. Conclusions: These results suggest that both ketorolac (1 mg/kg) and propacetamol (30 mg/kg) have no preemptive analgesic effects during 1 hour after adenotonsillectomy. (Korean J Anesthesiol 2009; 57: 308∼13)

Propofol and remifentanil are both rapid and short-acting drugs that can be used for sedation and analgesia during monitored anesthesia care (MAC). This study was designed to determine the optimal infusion rates of remifentanil during propofol anesthesia in patient undergoing the varicose vein endovenous laser therapy. Methods: In this randomized, double-blind study, we evaluated the effects of different remifentanil infusion rates on the requirement doses of propofol, level of sedation, intraoperative recall, respiratory and cardiovascular variables, and recovery. Forty consenting ASA physical status I or II patients undergoing endovenous laser therapy with 1% lidocaine skin infiltration were randomly assigned to one of two treatment groups. All patients received midazolam 0.05 mg/kg intravenously for premedication. Remifentanil was infused at 0.05 or 0.10μg/kg/min during the anesthesia. Sedation was evaluated using the Observer's Assessment of Alertness/Sedation (OAA/S) scale at 5 min intervals by a blinded observer and continuous BIS monitor. The propofol infusion was started from the rate, 3 mg/kg/hr, and subsequently varied to maintain patient comfort, sedation, stable cardiovascular and respiratory function. Results: Higher infusion rates of remifentanil (0.10μg/kg/min) produced significant respiratory depression (P ＜ 0.05). The infused total doses of propofol were not different from each other significantly. Conclusions: This study demonstrated that administration of propofol at 3.4 ± 1.3 mg/kg/hr with a remifentanil infusion at 0.05μg/kg/min is the optimal dosing regimen to provide sedation, analgesia and amnesia with a low incidence of side effects, such as respiratory depression in the patients premedicated with midazolam undergoing varicose vein endovenous laser therapy.

Background: There is a high incidence of pain following injection of propofol, and many studies have been conducted to find a way of reducing this. The administration of lidocaine and recently, remifentanil has also been used for this purpose in adults, but has been only partially effective. Thus, the purpose of this study was to investigate the analgesic effect of remifentanil alone, the premixture of lidocaine and both remifentanil and lidocaine and to compare either treatment alone during propofol injection in dorsal hand-veins in the pediatric patients. Methods: In a randomized, double-blind, prospective trial, 120 pediatric patients were allocated to one of four groups (each n = 30) receiving normal saline, remifentanil (0.5μg/kg), lidocaine (0.3 mg/kg) and remifentanil (0.5μg/kg) plus lidocaine (0.3 mg/kg) as pretreatment, followed by injection of 2% propofol (3 mg/kg). Pain was assessed on a four-point scale (none, mild, moderate, severe) during propofol injection. Mean arterial blood pressure and heart rates were measured before and after propofol injection. Results: The remifentanil, lidocaine and remifentanil plus lidocaine groups showed significantly less frequent and intense pain than the normal saline group. There are no significant change of mean arterial blood pressure and heart rate except normal saline group. The remifentanil and remifentanil plus lidocaine groups provided more pain relief than the lidocaine group. Conclusions: The combination of remifentanil and premixture of lidocaine with propofol is the most effective method to prevent propofol-induced pain with hemodynamic stability in the pediatr ic patients. (Korean J Anesthesiol 2008; 54: 400～5)

Background: Remifentanil is a useful and relatively safe opioid, but acute tolerance to it frequently develops, as patients who have received remifentanil based anesthesia often suffer postoperative hyperalgesia. This study investigated whether a small dose of ketamine, an N-methyl-D-aspartate (NMDA) receptor antagonist, can attenuate postoperative pain suffered with remifentanil anesthesia. Methods: 32 patients who were scheduled to undergo laparoscopic cholecystectomy were randomly assigned to two groups: a ketamine group (group K) and a control group (group C). All patients were given remifentanil by target controlled infusion (TCI) to the effect site (concentrations: 4.0−6.0 ng/ml). Just before incision patients in group K received 0.15 mg/kg ketamine intravenously and patients in group C received the same volume, but only of normal saline. Pain scores measured by Numerical Rating Scale (NRS) and additional use of analgesics were immediately recorded by a blinded investigator at the post-anesthesia care unit (PACU) and general ward up to 24 hours after surgery. Results: The average NRS scores upon arrival to PACU, 5, 10, 15 and 30 min in PACU, and 5 hours after discharge from PACU were significantly lower in group K than group C. The frequency of additional analgesics use was also significantly lower in group K. Conclusions: It is suggested that a small dose of ketamine attenuates the postoperative pain felt with remifentanil anesthesia. This finding also suggests that ketamine may decrease the possible acute tolerance developed with remifentanil anesthesia. (Korean J Anesthesiol 2008; 54: 146∼51)

Background: This study compared the hemodynamic effects of target-controlled infusion (TCI) of remifentanil (4, 5, or 6 ng/ml) during propofol induction in normotensive and hypertensive patients. It was also examined whether increasing the remifentanil concentrations might reduce propofol consumption at the loss of consciousness (LOC). Methods: Seventy five ASA 1 or 2 normotensive (N) and 75 ASA 2 hypertensive (H) patients were randomly allocated according to the remifentanil target effect-site concentration of 4, 5, 6 ng/ml (groups N4, N5, N6, H4, H5, H6 respectively). After the start of remifentanil TCI, when the target effect-site concentration of remifentanil had been reached, the TCI of propofol (4μg/ml) was started. The effect-site concentration of propofol at LOC was recorded. When the target effect-site concentration of propofol was reached, 0.6 mg/kg of rocuronium was administered. Tracheal intubation was carried out after 2 minutes. The noninvasive blood pressure, heart rate (HR), bispectral index (BIS) and infused dose of remifentanil and propofol were recorded. Results: Groups H5, H6 and N6 resulted in significant decrease in blood pressure after intubation. In groups N4 and H4, clinically significant increases in HR (above 25% of the baseline) were observed at 1 minute after intubation. The effect-site concentration of propofol at LOC was significantly lower in groups N6 and H6 compared to groups N4 and H4. Conclusions: In hypertensive patients, a dosing requirement of lower effect-site concentration of 4 ng/ml remifentanil might be adequate during propofol induction. Increasing the remifentanil concentrations from 4 to 6 ng/ml may reduce the propofol requirements for hypnosis. (Korean J Anesthesiol 2007; 53: S 12∼8)

Background: Emergence agitation is one of the major problems in pediatric anesthesia. The aim of this study was to compare the effect of remifentanil and fentanyl on the incidence of emergence agitation, postoperative pain and postoperative vomiting after administering anesthesia with sevoflurane. Methods: Thirty ASA physical status 1−2 children, aged 12−60 months undergoing a unilateral inguinal herniorrhaphy were randomized to receive either remifentanil (group R, bolus 0.5μg/kg; infusion 0.2μg/kg/min) or fentanyl (group F, 1μg/kg) after thiopental sodium induction. All patients received sevoflurane for maintenance of anesthesia. Heart rate and blood pressure were measured at baseline (T0), preintubation (T1), postintubation (T2) and 5 minutes after intubation (T3). The agitation score, pain score and incidence of postoperative vomiting were assessed upon arrival at the recovery room (P0), 30 minutes thereafter (P1) and 3 hours after discharge from the recovery room (P2). Results: The agitation score were higher in group R at P0 (P ＜ 0.05). The pain score was higher in group R at P0, P1 and P2 (P ＜ 0.05). Postoperative vomiting was present only in one patient in group F. Conclusions: Adjuvant use of fentanyl during sevoflurane anesthesia revealed advantages over the use of remifentanil concerning the incidence of postoperative agitation and pain without any prolongation of recovery time. (Korean J Anesthesiol 2007; 53: 609～14)