Analgesic Effect of Toll-like Receptor 4 Antagonistic Peptide 2 on Mechanical Allodynia Induced with Spinal Nerve Ligation in Rats

Neuroinflammation is one of the key mechanisms of neuropathic pain, which is primarily mediated by the Toll-like receptor 4 (TLR4) signaling pathways in microglia. Therefore, TLR4 may be a reasonable target for treatment of neuropathic pain. Here, we examined the analgesic effect of TLR4 antagonistic peptide 2 (TAP2) on neuropathic pain induced by spinal nerve ligation in rats. When lipopolysaccharide (LPS)-stimulated BV2 microglia cells were treated with TAP2 (10 µM), the mRNA levels of proinflammatory mediators, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, cyclooxygenase (COX)-2, and inducible nitric oxide synthase (iNOS), were markedly decreased by 54–83% as determined by quantitative PCR (qPCR) analysis. Furthermore, when TAP2 (25 nmol in 20 µL PBS) was intrathecally administered to the spinal nerve ligation-induced rats on day 3 after surgery, the mechanical allodynia was markedly decreased for approximately 2 weeks in von Frey filament tests, with a reduction in microglial activation. On immunohistochemical and qPCR analyses, both the level of reactive oxygen species and the gene expression of the proinflammatory mediators, such as TNF-α, IL-1β, IL-6, COX-2, and iNOS, were significantly decreased in the ipsilateral spinal dorsal horn. Finally, the analgesic effect of TAP2 was reproduced in rats with monoiodoacetate-induced osteoarthritic pain. The findings of the present study suggest that TAP2 efficiently mitigates neuropathic pain behavior by suppressing microglial activation, followed by downregulation of neuropathic pain-related factors, such as reactive oxygen species and proinflammatory molecules. Therefore, it may be useful as a new analgesic for treatment of neuropathic pain.

Appropriate angle and depth in thoracic transforaminal epidural block in Koreans

BACKGROUND: Selective transforaminal epidural block has come to the for as a targetspecific modality in the treatment and diagnosis of spinal pain. Thoracic transforaminal epidural block (TTFEB) has the associated risk of pneumothorax. This article describes a retrospective study conducted using computed tomography (CT) imaging to investigate the TTFEB angle and depth appropriate to minimize the risk of pneumothorax in Koreans. METHODS: The subjects of the present study were 100 randomly selected patients between 50 and 70 years of age found be free of thoracic disease according to chest CT performed in the present hospital. On the chest CT, the superior, middle, and inferior thoracic vertebrae were observed at the T2, T7, and T11 levels, respectively. RESULTS: The average distance and the needle insertion angle from the skin point at which the needle may be inserted without piercing the lung to the intervertebral foramen were 117.8 ± 12.1 mm and 58.1 ± 6.1° at the T2 level, 85.6 ± 10.0 mm and 61.7 ± 4.3° at the T7 level, and 94.3 ± 8.7 mm and 64.4 ± 7.0° at the T11 level, respectively. CONCLUSIONS: The needle insertion at the point further than 40 mm, on the upper, middle thorax, if the needle pass from the inner vertebral body to lamina, it could be safer. However, on the lower thorax, needle could pierce the lung though the needle start from the inner vertebral body. Thus, it can be safer if the needle pass toward the exterior margin of lamina.

Effect of an epinephrine mixture for interscalene block on hemodynamic changes after the beach chair position under general anesthesia: a retrospective study / 대한마취과학회지

BACKGROUND: The beach chair position (BCP) can cause significant hypotension. Epinephrine is used to prolong the duration of local anesthetics; it is also absorbed into blood and can exert systemic effects. This study determined the effects of epinephrine mixed with ropivacaine for an interscalene block (ISB) on hemodynamic changes related to BCP. METHODS: Patient data collected from March 2013 to August 2014 were used retrospectively. We divided the patients into three groups: 1) ISB only, 2) I+G (general anesthesia after ISB without epinephrine), and 3) I+E+G (general anesthesia after ISB with epinephrine). Mean blood pressure (MBP) and heart rate (HR) were measured for 30 minutes at 5-minute intervals. RESULTS: The study analyzed data from 431 patients. MBP tended to decrease gradually in the groups I+G and I+E+G. There were significant differences in MBP between the groups I+G and I, and between the groups I+G and I+E+G. Group I+E+G showed a significant increase in HR compared with the other two groups. CONCLUSIONS: ISB with an epinephrine mixture did not prevent hypotension caused by the BCP after general anesthesia. HR increased only in response to the epinephrine mixture. A well-planned prospective study is required to compare hemodynamic changes in that context.

Acute traumatic injury and delayed airway obstruction after the use of a GlideScope in a patient with a difficult airway: A case report

Endotracheal intubation sometimes leads to complications, particularly in patients with anticipated difficult intubation. The GlideScope is preferred because of its high success rate in cases with anticipated difficult intubation. However, complications during the process have been reported. Most minor injuries can be treated after early detection. However, treatment can be difficult if complications occur later. We report a patient who underwent an emergency tracheostomy due to a delayed airway obstruction caused by pharyngeal wall bleeding during intubation with a GlideScope.

Use of 18F-FDG PET to predict tumor progression and survival in patients with intermediate hepatocellular carcinoma treated by transarterial chemoembolization

BACKGROUND/AIMS: 18F-Fluorodeoxyglucose positron-emission tomography (18F-FDG PET) has been used to assess the biological behavior of hepatocellular carcinoma (HCC). In this study, we investigated the usefulness of 18F-FDG PET for predicting tumor progression and survival in patients with intermediate Barcelona Clinic Liver Cancer (BCLC) intermediate-stage HCC treated by transarterial chemoembolization (TACE). METHODS: From February 2006 to March 2013, 210 patients treated with TACE, including 77 patients with BCLC intermediate-stage HCC, underwent examination by 18F-FDG PET. 18F-FDG uptake was calculated based on the tumor maximum (Tmax) standardized uptake value (SUV), the liver mean (Lmean) SUV, and the ratio of the Tmax SUV to the Lmean SUV (Tmax/Lmean). RESULTS: The mean follow-up period for the 77 patients (52 males, 25 females; average age, 63.3 years) was 22.2 months. The median time to progression of HCC in patients with a low Tmax/Lmean ( or = 1.83) was 17 and 6 months, respectively (p < 0.001). The median overall survival time of patients with a low and high Tmax/Lmean was 44 and 14 months, respectively (p = 0.003). Multivariate analysis revealed that the Tmax/Lmean was an independent predictor of overall survival (hazard ratio [HR], 1.96; 95% confidence interval [CI], 1.210 to 3.156; p = 0.006) and tumor progression (HR, 2.05; 95% CI, 1.264 to 3.308; p = 0.004). CONCLUSIONS: 18F-FDG uptake calculated by the Tmax/Lmean using PET predicted tumor progression and survival in patients with BCLC intermediate-stage HCC treated by TACE.

Suggested guidelines for vaccination of pigs in Korea

There is no published guideline for the vaccination to pigs even though several vaccine companies suggested the program based on their products. It is very difficult to standardize the program because most of the veterinary vaccines are containing several multivalent antigens depending on the companies. Now, we are suggesting the vaccine programs based on the current situation.

Complex Regional Pain Syndrome: Time to Study the Supraspinal Role?

No abstract available.

Intrathecal Administration of Mesenchymal Stem Cells Reduces the Reactive Oxygen Species and Pain Behavior in Neuropathic Rats

BACKGROUND: Neuropathic pain induced by spinal or peripheral nerve injury is very resistant to common pain killers, nerve block, and other pain management approaches. Recently, several studies using stem cells suggested a new way to control the neuropatic pain. In this study, we used the spinal nerve L5 ligation (SNL) model to investigate whether intrathecal rat mesenchymal stem cells (rMSCs) were able to decrease pain behavior, as well as the relationship between rMSCs and reactive oxygen species (ROS). METHODS: Neuropathic pain of the left hind paw was induced by unilateral SNL in Sprague-Dawley rats (n = 10 in each group). Mechanical sensitivity was assessed using Von Frey filaments at 3, 7, 10, 12, 14, 17, and 24 days post-ligation. rMSCs (10 microl, 1 x 105) or phosphate buffer saline (PBS, 10 microl) was injected intrathecally at 7 days post-ligation. Dihydroethidium (DHE), an oxidative fluorescent dye, was used to detect ROS at 24 days post-ligation. RESULTS: Tight ligation of the L5 spinal nerve induced allodynia in the left hind paw after 3 days post-ligation. ROS expression was increased significantly (P < 0.05) in spinal dorsal horn of L5. Intrathecal rMSCs significantly (P < 0.01) alleviated the allodynia at 10 days after intrathecal injection (17 days post-ligation). Intrathecal rMSCs administration significantly (P < 0.05) reduced ROS expression in the spinal dorsal horn. CONCLUSIONS: These results suggest that rMSCs may modulate neuropathic pain generation through ROS expression after spinal nerve ligation.

Successful anesthesia in a patient with a history of cardiac arrest following rocuronium injection / 대한마취과학회지

No abstract available.

Successful anesthesia in a patient with a history of cardiac arrest following rocuronium injection / 대한마취과학회지

No abstract available.

Glomus Tumor Causing Anterior Thigh Pain: A Case Report

Glomus tumors are a rare, benign neoplasm and 75% exist in the subungual region. Extradigital glomus tumors are much more difficult to diagnose because of their atypical location and symptoms. Furthermore, if their symptoms are similar to neuropathic pain, the patient can suffer from misdirected treatment due to misdiagnosis. It is essential to perform careful evaluation of the lesion itself in order to reduce misdiagnosis. Ultrasonography is a useful, non-invasive method that can be easily performed in the pain clinic for local evaluation and diagnosis. We report a case of misdiagnosed glomus tumor in the thigh which was properly diagnosed after ultrasonography.

Comparison of postoperative renal and hepatic function between desflurane-remifentanil and propofol-remifentanil for nephrectomy

BACKGROUND: Choice of anesthetics in patients with a history of nephrectomy is very important for anesthesiologists. It is important for the anesthesiologist to preserve the ipsilateral kidney function and minimize deleterious effects. This study was performed to compare anesthetic agents on postoperative renal and hepatic function in patients who underwent nephrectomy. METHODS: From 2008 to 2012, 116 patients who underwent nephrectomy in our hospital were evaluated through a retrospective study. Anesthesia was maintained with desflurane-remifentanil in the desflurane group (Group D), and propofol-remifentanil, using a target controlled infusion pump (Group T). In order to evaluate postoperative renal and hepatic function, blood urea nitrogen (BUN), serum creatinine (Cr), estimated glomerular filtration rate (eGFR), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) was measured preoperatively, postoperative day 1, 3 and 7. RESULTS: When compared to preoperative measures, Cr and BUN levels were elevated on postoperative day 1, 3 and 7 while eGFR was decreased in both groups. There was no significant difference between the two groups. AST and ALT were also mildly elevated on postoperative day 1, 3 and 7 in both groups. There was also no significant difference between the two groups. CONCLUSIONS: Anesthesia with desflurane-remifentanil or propofol-remifentanil alter postoperative renal and hepatic function with no significant difference between groups. Both desflurane and propofol may be chosen for general anesthesia undergoing nephrectomy patients.

Comparison of postoperative renal and hepatic function between desflurane-remifentanil and propofol-remifentanil for nephrectomy

BACKGROUND: Choice of anesthetics in patients with a history of nephrectomy is very important for anesthesiologists. It is important for the anesthesiologist to preserve the ipsilateral kidney function and minimize deleterious effects. This study was performed to compare anesthetic agents on postoperative renal and hepatic function in patients who underwent nephrectomy. METHODS: From 2008 to 2012, 116 patients who underwent nephrectomy in our hospital were evaluated through a retrospective study. Anesthesia was maintained with desflurane-remifentanil in the desflurane group (Group D), and propofol-remifentanil, using a target controlled infusion pump (Group T). In order to evaluate postoperative renal and hepatic function, blood urea nitrogen (BUN), serum creatinine (Cr), estimated glomerular filtration rate (eGFR), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) was measured preoperatively, postoperative day 1, 3 and 7. RESULTS: When compared to preoperative measures, Cr and BUN levels were elevated on postoperative day 1, 3 and 7 while eGFR was decreased in both groups. There was no significant difference between the two groups. AST and ALT were also mildly elevated on postoperative day 1, 3 and 7 in both groups. There was also no significant difference between the two groups. CONCLUSIONS: Anesthesia with desflurane-remifentanil or propofol-remifentanil alter postoperative renal and hepatic function with no significant difference between groups. Both desflurane and propofol may be chosen for general anesthesia undergoing nephrectomy patients.

Antinociceptive drug interaction between intrathecal vitamin E and gabapentin in the rat formalin test / 대한마취과학회지

BACKGROUND: Gabapentin is thought to exert an effect through the voltage-dependent calcium channel. Vitamin E is a widely known antioxidant which neutralizes the harmful effect of ROS which is considered to play a prominent role in various painful conditions. This study was therefore conducted to assess the antinociceptive effects of gabapentin and vitamin E and the interaction of these drugs in the modulation of pain in rats subjected to a formalin test. METHODS: Sprague-Dawley rats with a lumbar intrathecal catheter were tested for their paw flinches by 5% formalin injection after intrathecal injection of gabapentin or vitamin E. After obtaining dose-response curves for each drug, the effect of the combination was tested by the total dose fraction value and isobolographic analysis. RESULTS: When a single drug was injected intrathecally, significant dose-dependent decreases in flinches were shown only in the late phase. ED50 values of intrathecal gabapentin and vitamin E in the late phase were 75.3 +/- 9.58 microg, and 17.56 +/- 1.65 mg/kg respectively. The combination of gabapentin and vitamin E produced dose-dependent decreases in the number of flinches in both phases induced by the formalin test. The ED50 value of the combination was lower than the theoretical additive values in the late phase, but did not show a significant difference with the theoretical additive value. CONCLUSIONS: Gabapentin and vitamin E (by itself) have no antinociceptive effect in the early phase; however their combination has shown an antinociceptive effect. In addition, they show additive effects in the late phase of the formalin test.

Antinociceptive effect of phenyl N-tert-butylnitrone, a free radical scavenger, on the rat formalin test / 대한마취과학회지

BACKGROUND: Reactive oxygen species (ROS) such as superoxide radicals, hydrogen peroxide, nitric oxide, and nitroperoxide, cause oxidative stress which interferes with normal cell functioning, resulting in cell damage. It is reported to be associated with chronic pain, especially neuropathic pain, and inflammatory pain. ROS is also closely related to central sensitization. Therefore, this study was designed to explore the effects of Phenyl N-tert-butylnitrone (PBN), an ROS scavenger, in acute, continuous, and increasing pain caused by central sensitization. METHODS: Male Sprague-Dawley rats were divided into 2 groups, an intraperitoneal group (IP) and an intrathecal group (IT), and once again divided into an experimental group and a control group. The experimental group was injected with Phenyl N-tert-butylnitrone (PBN), a free radical scavenger, either intraperitoneally or intrathecally. After inducing pain by injecting formalin into the hind paw, pain behaviors were measured. Lumbar enlargement immmunohistochemistry was performed to assess nitrotyrosine, an oxidative stress marker, to identify the degree of protein nitration. RESULTS: Both experimental groups of IP and IT showed statistically significant decreases in the number of flinches compared to the control group in phase 1 and 2. Immunohistochemical evaluation in the control group revealed an increase in nitrated proteins in the gray matter of the lumbar spinal cord, but a significant decrease in nitrated proteins in the gray matter of lumbar spinal cord of the experimental group. CONCLUSIONS: Intraperitoneal and intrathecal administration of PBN decreases analgesic behaviors, allowing us to believe that ROS is mainly responsible for acute pain and central sensitization.

Antinociceptive effect of phenyl N-tert-butylnitrone, a free radical scavenger, on the rat formalin test / 대한마취과학회지

BACKGROUND: Reactive oxygen species (ROS) such as superoxide radicals, hydrogen peroxide, nitric oxide, and nitroperoxide, cause oxidative stress which interferes with normal cell functioning, resulting in cell damage. It is reported to be associated with chronic pain, especially neuropathic pain, and inflammatory pain. ROS is also closely related to central sensitization. Therefore, this study was designed to explore the effects of Phenyl N-tert-butylnitrone (PBN), an ROS scavenger, in acute, continuous, and increasing pain caused by central sensitization. METHODS: Male Sprague-Dawley rats were divided into 2 groups, an intraperitoneal group (IP) and an intrathecal group (IT), and once again divided into an experimental group and a control group. The experimental group was injected with Phenyl N-tert-butylnitrone (PBN), a free radical scavenger, either intraperitoneally or intrathecally. After inducing pain by injecting formalin into the hind paw, pain behaviors were measured. Lumbar enlargement immmunohistochemistry was performed to assess nitrotyrosine, an oxidative stress marker, to identify the degree of protein nitration. RESULTS: Both experimental groups of IP and IT showed statistically significant decreases in the number of flinches compared to the control group in phase 1 and 2. Immunohistochemical evaluation in the control group revealed an increase in nitrated proteins in the gray matter of the lumbar spinal cord, but a significant decrease in nitrated proteins in the gray matter of lumbar spinal cord of the experimental group. CONCLUSIONS: Intraperitoneal and intrathecal administration of PBN decreases analgesic behaviors, allowing us to believe that ROS is mainly responsible for acute pain and central sensitization.

Antinociceptive Effects of Intraperitoneal and Intrathecal Vitamin E in the Rat Formalin Test

BACKGROUND: Vitamin E is widely known to be one of the reactive oxygen species (ROS) scavengers and a drug that can easily be obtained, and it has been shown to attenuate the pain responses induced by various causes in animal pain models. Thus, this experiment was conducted to assess the antinociceptive effects of vitamin E by comparing intraperitoneal and intrathecal injections in rats subjected to the formalin test. METHODS: After the intraperitoneal and intrathecal injections of vitamin E were carried out, respectively (IP: 500 mg/kg, 1 g/kg, and 2 g/kg, IT: 3 mg/kg, 10 mg/kg, and 30 mg/kg), the formalin test was perfumed. As soon as 5% formalin was injected into left hind paw, the number of flinches induced by pain was measured at 5-minute intervals for 1 hour. RESULTS: Formalin injected into the left hind paw induced biphasic nociceptive behavior in all animals. Intraperitoneal injection of vitamin E diminished the nociceptive behavior in a dose-dependent manner during the early and late phase. Intrathecal vitamin E diminished nociceptive behavior dose dependently during the late phase but showed no significant difference in the early phase. CONCLUSIONS: Vitamin E attenuated acute nociception when it was injected systemically, while both systemic and intrathecal injection produced analgesia in a rat model of formalin-induced hyperalgesia.

Ultrasonographic Measurement of the Ligamentum Flavum Depth; Is It a Reliable Method to Distinguish True and False Loss of Resistance?

BACKGROUND: Previous studies have shown that if performed without radiographic guidance, the loss of resistance (LOR) technique can result in inaccurate needle placement in up to 30% of lumbar epidural blocks. To date, no study has shown the efficacy of measuring the depth of the posterior complex (ligamentum flavum, epidural space, and posterior dura) ultrasonographically to distinguish true and false LOR. METHODS: 40 cervical epidural blocks were performed using the LOR technique and confirmed by epidurograms. Transverse ultrasound images of the C6/7 area were taken before each cervical epidural block, and the distances from the skin to the posterior complex, transverse process, and supraspinous ligament were measured on each ultrasound view. The number of LOR attempts was counted, and the depth of each LOR was measured with a standard ruler. Correlation of false and true positive LOR depth with ultrasonographically measured depth was also statistically analyzed. RESULTS: 76.5% of all cases (26 out of 34) showed false positive LOR. Concordance correlation coefficients between the measured distances on ultrasound (skin to ligamentum flavum) and actual needle depth were 0.8285 on true LOR. Depth of the true positive LOR correlated with height and weight, with a mean of 5.64 +/- 1.06 cm, while the mean depth of the false positive LOR was 4.08 +/- 1.00 cm. CONCLUSIONS: Ultrasonographic measurement of the ligamentum flavum depth (or posterior complex) preceding cervical epidural block is beneficial in excluding false LOR and increasing success rates of cervical epidural blocks.

Effects of intraoperative low dose ketamine on remifentanil-induced hyperalgesia in gynecologic surgery with sevoflurane anesthesia / 대한마취과학회지

BACKGROUND: Remifentanil is useful during general anesthesia because of its rapid onset and short acting time. However, some studies report that due to opioid-induced hyperalgesia (OIH) and tolerance, remifentanil also increases early postoperative pain. The occurrence of OIH and opioid-induced tolerance is mainly thought to be due to central sensitization by the activation of NMDA receptors. Therefore, we investigated the effects of continuous infusion of ketamine, an NMDA receptor antagonist, on postoperative pain and the quantity of opioids used. METHODS: 40 patients scheduled to undergo laparoscopic gynecologic surgery were randomly allocated into two groups. Anesthesia was equally maintained with sevoflurane and 4 ng/ml of remifentanil in all patients. Ketamine (0.3 mg/kg) was injected and followed with a continuous dosage of 3 microl/kg/min in the ketamine group (n = 20) while the control group was injected and infused with an equal amount of normal saline. We compared postoperative VAS up to 7 hours and morphine demand through PCA. RESULTS: Postoperative VAS and morphine demand was significantly lower in the ketamine group 2 and 3 hours after surgery, respectively. CONCLUSIONS: When general anesthesia is maintained with sevoflurane and remifentanil in patients undergoing laparoscopic gynecologic surgery, continuous infusion of low dose ketamine decreased early postoperative pain and the quantity of opioids used.

Effect of a small dose of propofol or ketamine to prevent coughing and laryngospasm in children awakening from general anesthesia / 대한마취과학회지

BACKGROUND: Coughing during emergence from general anesthesia may be detrimental in children. We compared the effect of a small dose of propofol or ketamine administered at the end of sevoflurane anesthesia on the incidence or severity of coughing in children undergoing a minimal invasive operation. METHODS: One hundred and eighteen children aged between 3 and 15 years, American Society of Anesthesiologists (ASA) status I, were enrolled in this randomized double blind study. Anesthesia was induced with propofol or ketamine and maintained with sevoflurane in N2O/O2. Each group received propofol 0.25 mg/kg or ketamine 0.25 mg/kg and the control group received saline 0.1 ml/kg. The decision to perform tracheal extubation was based on specified criteria, including the resumption of spontaneous respiration. During emergence from anesthesia and extubation, coughing was observed and graded at predefined times. RESULTS: The incidence of emergence without coughing was higher in the propofol group than in the ketamine and control group (19%, 11% and 6%, respectively), whereas the incidence of severe coughing was higher in the control group than in propofol and ketamine group (17.14%, 10.0% and 6.98%, respectively). CONCLUSIONS: The addition of propofol 0.25 mg/kg decreased the incidence of coughing after sevoflurane general anesthesia in children undergoing non-painful procedures.