Diabetic Neuropathy and Minimum Effective Anesthetic Concentration of Mepivacaine for Axillary Brachial Plexus Block: A Prospective Observational Study.

Nerves in patients with diabetic neuropathy (DN) show increased susceptibility to local anesthetics, potentially requiring a decreased dose. We investigated whether the minimum effective anesthetic concentration (MEAC) of mepivacaine for successful axillary block is lower in patients with DN than in those without. This prospective observational study included patients with DN (n = 22) and without diabetes (n = 22) at a tertiary care center. Patients received an ultrasound-guided axillary block with 30 mL of mepivacaine for anesthesia. The mepivacaine concentration used in each patient was calculated using Dixon's up-and-down method. A block was considered successful if all four sensory nerves had a score of 1 or 2 within 30 min with no pain during surgery. The primary outcome was the MEAC of mepivacaine, and the secondary outcomes included the minimal nerve stimulation intensity for the musculocutaneous nerve and the occurrence of adverse events. The MEAC50 was 0.55% (95% CI 0.33-0.77%) in patients without diabetes and 0.58% (95% CI 0.39-0.77%) in patients with DN (p = 0.837). The MEAC90 was 0.98% (95% CI 0.54-1.42%) in patients without diabetes and 0.96% (95% CI 0.57-1.35%) in patients with DN (p = 0.949). The stimulation threshold for the musculocutaneous nerve was significantly different between groups (0.49 mA vs. 0.19 mA for patients with vs. without diabetes; p = 0.002). In conclusion, the MEAC of mepivacaine for a successful axillary block is not lower in patients with DN.

A Randomized Comparison of Multimodal Analgesia and Fentanyl-Based Patient-Controlled Analgesia in Women Undergoing Robot-Assisted Bilateral Axillary Breast Approach Thyroidectomy.

Opioid-free multimodal analgesia (MMA) emerges as a preferable approach for postoperative pain management compared to opioid-based patient-controlled analgesia (PCA) in robot-assisted bilateral axillary breast approach thyroidectomy, a procedure commonly undergone by young female patients. We compared the analgesic efficacy and other recovery profiles between MMA and PCA. In total, 88 female patients were administered fentanyl-based PCA or the combination of lidocaine continuous infusion and nefopam injection before recovery from general anesthesia. The visual analog scale score of postoperative pain was assessed at the post-anesthesia care unit and at 6, 12, and 24 h after the termination of surgery. Postoperative nausea and vomiting (PONV), rescue analgesic and anti-emetic agents, recovery profiles, and adverse events were also compared. The median numeric rating scores on postoperative pain at 6 h after recovery from general anesthesia were three in both groups, with no significant difference between the groups at any time point. The PONV incidence was significantly higher in the PCA group than in the MMA group. The combination of systemic lidocaine infusion and nefopam injection has an analgesic effect equivalent to that of fentanyl-based PCA without PONV.

Comparison of the Effects of Lumbar Spine Flexion on the Acoustic Windows Between Young and Elderly Patients.

BACKGROUND: The effects of lumbar flexion on posterior longitudinal ligament (PLL) length as an acoustic window for neuraxial block in older patients have not been fully elucidated. OBJECTIVE: This study aimed to compare changes in PLL length during lumbar spine flexion in young and old patients. STUDY DESIGN: Observational cohort study. SETTING: Tertiary University Hospital. METHODS: Forty young and older adult patients were placed in the lateral decubitus position. To flex the lumbar spine, patients were asked to flex their hips and knees and then their neck and shoulder toward their knees as much as they could (fetal position). An assistant pushed the patients' abdomen to the back and held their neck and legs to help them maintain position. To obtain an optimal ultrasound view, lumbar spinal ultrasonography was performed from L5/S1 to L2/L3 using a paramedian oblique sagittal plane. PLL lengths were measured on the ultrasound image before fetal position, after unassisted fetal position, and after assisted fetal position. RESULTS: PLL lengths increased after lumbar spine flexion in both young and older adult  patients, except at the L3-L4 level in old patients. The change in PLL length during lumbar spine flexion was significantly lower in old patients than in young patients at the L5-S1 and L3-L4 levels (P = 0.0028 and P = 0.0134, respectively). After lumbar spine flexion, the PLL length was significantly different between the spinal levels in older patients (P = 0.0392). LIMITATIONS: First, we measured the PLL length as an acoustic window for neuraxial block using lumbar spinal ultrasonography. Second, the researcher who obtained the spinal ultrasound view was not blinded to the patient's group and position. However, the researcher who measured the PLL lengths on ultrasonography was blinded. Third, all participants had no history of surgery, trauma, or congenital abnormalities of the spine, regardless of age. CONCLUSION: Lumbar spine flexion can increase PLL length in young and old patients. However, lumbar spine flexion is less effective in increasing the PLL length in old patients than in young patients.

Comparison of Thoracic Epidural Access with Lateral Decubitus and Shoulder Rotation Positions for Repeat Thoracic Epidural Blockade.

BACKGROUND: Shoulder rotation has been shown to increase the acoustic window of ultrasound for thoracic epidural access. However, this effect of shoulder rotation has not yet been confirmed in clinical practice. OBJECTIVE: This study aimed to evaluate the effects of shoulder rotation on the thoracic epidural blockade in patients with acute or chronic pain in the thoracic region. STUDY DESIGN: Prospective crossover trial. SETTING: Pain clinic of our university in the Republic of Korea. METHODS: Forty patients aged 20 - 80 years with acute or chronic pain in the thoracic region who were scheduled to undergo thoracic epidural blockade more than twice. INTERVENTIONS: The patients underwent repeated fluoroscopy-guided thoracic epidural blockade via the paramedian approach in the lateral decubitus position either with or without shoulder rotation.The primary outcome measure was the attempt time to the confirmed spread of contrast. The number of attempts, total procedure time, vertical interpedicular distance, contrast spreading length, and complications were compared between the 2 positions. RESULTS: The median attempt times in the lateral decubitus and shoulder rotation positions were 138.8 and 132.5 seconds, respectively, and this difference was significant (P = 0.004). Compared with the lateral decubitus position, the shoulder rotation position was also associated with a significantly lower number of attempts (P = 0.03), shorter total procedure time (P < 0.001), and greater vertical interpedicular and contrast spreading distances (P < 0.001 and P = 0.02, respectively). LIMITATIONS: The operator in this study was not blinded to the patient groups. Other researchers observed the operator's procedure and evaluated and recorded the data in an attempt to overcome this bias. However, it was difficult to completely avoid the bias. Second, epidural blockade was performed at various levels (T3-11), and the anatomical features vary among thoracic spine levels. CONCLUSIONS: The study findings demonstrate the clinical benefits of the shoulder rotation position versus the lateral decubitus position in terms of successful epidural access during thoracic epidural blockade using the paramedian approach.

Comparison of the Effects of Sufentanil and Fentanyl Intravenous Patient Controlled Analgesia after Lumbar Fusion.

OBJECTIVE: Postoperative pain is one of the major complaints of patients after lumbar fusion surgery. The authors evaluated the effects of intravenous patient controlled analgesia (IV-PCA) using fentanyl or sufentanil on postoperative pain management and pain-related complications. METHODS: Forty-two patients that had undergone surgery with lumbar instrumentation and fusion at single or double levels constituted the study cohort. Patients were equally and randomly allocated to a sufentanil group (group S) or a fentanyl group (group F) for patient controlled analgesia (PCA). Group S received sufentanil at a dose of 4 µg/kg IV-PCA and group F received fentanyl 24 µg/kg IV-PCA. A numeric rating scale (NRS) of postoperative pain was applied before surgery, and immediately and at 1, 6, and 24 hours (hrs) after surgery. Oswestry disability index (ODI) scores were obtained before surgery and one month after surgery. Opioid-related side effects were also evaluated. RESULTS: No significant intergroup difference was observed in NRS or ODI scores at any of the above-mentioned time points. Side effects were more frequent in group F. More specifically, nausea, vomiting rates were significantly higher (p=0.04), but pruritus, hypotension, and headache rates were non-significantly different in the two groups. CONCLUSION: Sufentanil displayed no analgesic advantage over fentanyl postoperatively. However, sufentanil should be considerable for patients at high risk of GI issues, because it had lower postoperative nausea and vomiting rates than fentanyl.

Prolonged hemidiaphragmatic paresis following continuous interscalene brachial plexus block: A case report.

Interscalene brachial plexus block provides effective anesthesia and analgesia for shoulder surgery. One of the disadvantages of this technique is the risk of hemidiaphragmatic paresis, which can occur as a result of phrenic nerve block and can cause a decrease in the pulmonary function, limiting the use of the block in patients with reduced functional residual capacity or a preexisting pulmonary disease. However, it is generally transient and is resolved over the duration of the local anesthetic's action.We present a case of a patient who experienced prolonged hemidiaphragmatic paresis following a continuous interscalene brachial plexus block for the postoperative pain management of shoulder surgery, and suggest a mechanism that may have led to this adverse effect.Nerve injuries associated with peripheral nerve blocks may be caused by several mechanisms. Our findings suggest that perioperative nerve injuries can occur as a result of combined mechanical and chemical injuries.

Seborrheic dermatitis treatment with stellate ganglion block: a case report.

Seborrheic dermatitis is a chronic recurrent inflammatory disorder presumed to be caused by increased sebaceous gland secretion, metabolic changes in the cutaneous microflora, and changes in the host immune function. Stellate ganglion block (SGB) is known to increase the blood flow rate without altering the blood pressure, heart rate, or cardiac output, to stabilize hypertonic conditions of the sympathetic nerves, and to affect the endocrine and immune systems. It is used in the differential diagnosis and treatment of autonomic nervous system disorders of the head, neck, and upper limbs. The authors report the first case of successful treatment of a patient with seborrheic dermatitis through repeated SGB trials.

Endotracheal intubation using i-gel® and lightwand in a patient with difficult airway: a case report.

This case report involves tracheal intubation using i-gel® in combination with a lightwand in a patient with a difficult airway, classified as Cormack-Lehane grade 3. I-gel® was used during anesthesia induction to properly maintain ventilation. The authors have previously reported successful tracheal intubation on a patient with a difficult airway through the use of i-gel® and a fiberoptic bronchoscope. However, if the use of a fiberoptic bronchoscope is not immediately available in a patient with a difficult airway, tracheal intubation may be performed by using i-gel® and a lightwand in a patient with difficult airway, allowing the safe induction of anesthesia.

Comparison of dexmedetomidine and epinephrine as an adjuvant to 1% mepivacaine in brachial plexus block.

BACKGROUND: Dexmedetomidine extends the duration of nerve block when administered perineurally together with local anesthetics by central and/or peripheral action. In this study, we compared the duration of nerve block between dexmedetomidine and epinephrine as an adjuvant to 1% mepivacaine in infraclavicular brachial plexus block. METHODS: Thirty patients, scheduled for upper limb surgery were assigned randomly to 3 groups of 10 patients each. We performed brachial plexus block using a nerve stimulator. In the control group (group C), patients received 40 ml of 1% mepivacaine. In group E, patients received 40 ml of 1% mepivacaine containing 200 µg of epinephrine as an adjuvant. In group D, patients received 40 ml of 1% mepivacaine containing 1 µg/kg of dexmedetomidine as an adjuvant. Sensory block duration, motor block duration, time to sense pain, and onset time were assessed. We also monitored blood pressure, heart rate, oxygen saturation and bispectral index. RESULTS: In group D and group E, sensory block duration, motor block duration and time to sense first pain were prolonged significantly compared to group C. However, there was no significant difference between group D and group E. CONCLUSIONS: Perineural 1 µg/kg of dexmedetomidine similarly prolonged nerve block duration compared to 200 µg of epinephrine, but slowed heart rate. Thus, dexmedetomidine is expected to be a good alternative as an adjuvant to local anesthesia in patients who are cautioned against epinephrine.

Comparison of the preventive effects of pretreatment of lidocaine with a tourniquet and a premixed injection of lidocaine on propofol-LCT/MCT injection pain.

BACKGROUND: Lidocaine has been used widely to prevent propofol injection pain. Various methods of administration exist, such as lidocaine premixed with propofol or lidocaine pretreatment using a tourniquet, but it is unclear which method of lidocaine administration is more effective for the prevention of injection pain of propofol LCT/MCT. The purpose of this study was to compare pretreatment of lidocaine with a tourniquet and a premixed injection of lidocaine to prevent injection pain of propofol-LCT/MCT. METHODS: Patients were randomly allocated into the pretreatment group (n = 117) or the premixed group (n = 117). The pretreatment group was pretreated with 2 ml of lidocaine 2%, held with a tourniquet, before propofol-LCT/MCT injection. The premixed group was injected with a premixed solution of propofol-LCT/MCT and 2 ml of lidocaine 2%. To evaluate the incidence and severity of pain, spontaneous verbal expressions of pain, movement of hand, frowning, and moaning were recorded, and the patients were asked to recall their pain with the visual analogue score (VAS) 30 minutes after awakening from anesthesia. RESULTS: Overall, injection pain occurred in 13.7% of the pretreatment group and 15.4% of the premixed group, without any statistical difference (P = 0.71). There was no difference in spontaneous verbal expressions of pain, movement of hand, frowning, and moaning between the two groups. The pain intensity (VAS) also showed no difference between the two groups (P = 0.49). CONCLUSIONS: Pretreatment of lidocaine with a tourniquet showed no more benefit to prevent injection pain of propofol LCT/MCT compared to a premixed injection with lidocaine.

Hypertensive crisis during wide excision of gastrointestinal stromal cell tumor (GIST): Undiagnosed paraganglioma -A case report-.

Although paraganglioma (PGL), an extra-adrenal retroperitoneal pheochromocytoma (PHEO), is a rare catecholamine-secreting neuroendocrine tumor, it can cause severe hypertensive crisis during anesthesia or surgery if undiagnosed preoperatively. Extraluminal perigastric masses may be presumed to be gastrointestinal stromal tumors (GISTs) or soft tissue sarcomas even when histologic confirmation is not possible. Therefore, without a histologic diagnosis or symptoms of excessive catecholamine secretion, PGL may be mistaken for GIST. We report a case of preoperatively undiagnosed PGL which caused hypertensive crisis during anesthesia for retroperitoneal mass excision.

Chitosan/TPP-hyaluronic acid nanoparticles: a new vehicle for gene delivery to the spinal cord.

Gene delivery offers therapeutic promise for the treatment of neurological diseases and spinal cord injury. Several studies have offered viral vectors as vehicles to deliver therapeutic agents, yet their toxicity and immunogenicity, along with the cost of their large-scale formulation, limits their clinical use. As such, non-viral vectors are attractive in that they offer improved safety profiles compared to viruses. Poly(ethylene imine) (PEI) is one of the most extensively studied non-viral vectors, but its clinical value is limited y its cytotoxicity. Recently, chitosan/DNA complex nanoparticles have een considered as a vector for gene delivery. Here, we demonstrate that DNA nanoparticles made of hyaluronic acid (HA) and chitosan have low cytotoxicity and induce high transgene expression in neural stem cells and organotypic spinal cord slice tissue. Chitosan-TPP/HA nanoparticles were significantly less cytotoxic than PEI at various concentrations. Additionally, chitosan-TPP/HA nanoparticles with pDNA induced higher transgene expression in vitro for a longer duration than PEI in neural stem cells. These results suggest chitosan-TPP/HA nanoparticles may have the potential to serve as an option for gene delivery to the spinal cord.

Outcome evaluation with signal activation of functional MRI in spinal cord injury.

OBJECTIVE: The authors investigated the changes of cortical sensorimotor activity in functional MRI (fMRI) and functional recovery in spinal cord injury (SCI) patients who had been treated by bone marrow cell transplantation. METHODS: Nineteen patients with SCI were included in this study; ten patients with clinical improvement and nine without. The cortical sensorimotor activations were studied using the proprioceptive stimulation during the fMRI. RESULTS: Diagnostic accuracy of fMRI with neurological improvement was 70.0% and 44.4% for sensitivity and specificity, respectively. Signal activation in the ipsilateral motor cortex in fMRI was commonly observed in the clinically neurological improved group (p-value=0.002). Signal activation in the contralateral temporal lobe and basal ganglia was more commonly found in the neurological unimproved group (p-value<0.001). Signal activation in other locations was not statistically different. CONCLUSION: In patients with SCI, activation patterns of fMRI between patients with neurologic recovery and those without varied. Such plasticity should be considered in evaluating SCI interventions based on behavioral and neurological measurements.

Cerebellar hemorrhage after spine fixation misdiagnosed as a complication of narcotics use -A case report-.

Cerebellar hemorrhage occurs mainly due to hypertension. Postoperative cerebellar hemorrhage is known to be associated frequently with frontotemporal craniotomy, but quite rare with spine operation. A 56-year-old female received spinal fixation due to continuous leg tingling sensation for since two years ago. Twenty-one hours after operation, she was disoriented and unresponsive to voice. Performed computed tomography showed both cerebellar hemorrhage. An emergency decompressive craniotomy was carried out to remove the hematoma. On the basis of this case, we reported this complications and reviewed related literature.

A clinical comparison of continuous interscalene brachial plexus block with different basal infusion rates of 0.2% ropivacaine for shoulder surgery.

BACKGROUND: A continuous interscalene brachial plexus block is a highly effective postoperative analgesic modality after shoulder surgery. However, there is no consensus regarding the optimal basal infusion rate of ropivacaine for a continuous interscalene brachial plexus block. A prospective, double blind study was performed to compare two different basal rates of 0.2% ropivacaine for a continuous interscalene brachial plexus block after shoulder surgery. METHODS: Sixty-two patients receiving shoulder surgery under an interscalene brachial plexus block were included. The continuous interscalene brachial plexus block was performed using a modified lateral technique with 30 ml of 0.5% ropivacaine. Surgery was carried out under an interscalene brachial plexus block or general anesthesia. After surgery, the patients were divided randomly into two groups containing 32 each. During the first 48 h after surgery, groups R8 and R6 received a continuous infusion of 0.2% ropivacaine at 8 ml/h and 6 ml/h, respectively. The pain scores at rest and on movement, supplemental analgesia, motor block, adverse events and patient's satisfaction were recorded. RESULTS: The pain scores, supplemental analgesia, motor block, adverse events and patient's satisfaction were similar in the two groups. CONCLUSIONS: When providing continuous interscalene brachial plexus block after shoulder surgery, 0.2% ropivacaine at a basal rate of 8 ml/h or 6 ml/h produces similar clinical efficacy. Therefore, decreasing the basal rate of CISB is more appropriate considering the toxicity of local anesthetics.

Right hydrothorax misconceived as atelectasis after left internal jugular vein catheterization -A case report-.

Central vein catheterization is a common procedure for monitoring the central venous pressure, securing vascular access, administrating vasoactive drugs and removing air embolisms. However, many complications can occur, such as vessel injury, pneumothorax, hydrothorax, nerve injury, arrhythmia and infection at the insertion site. We encountered an unusual complication of a localized right hydrothorax that was initially misinterpreted as an atelectasis after left internal jugular vein catheterization and right lateral positioning for a left lower lobectomy.

Evaluation of Spinal Fusion Using Bone Marrow Derived Mesenchymal Stem Cells with or without Fibroblast Growth Factor-4.

OBJECTIVE: In this study, the authors assessed the ability of rat bone marrow derived mesenchymal stem cells (BMDMSCs), in the presence of a growth factor, fibroblast growth factor-4 (FGF-4) and hydroxyapatite, to act as a scaffold for posterolateral spinal fusion in a rat model. METHODS: Using a rat posterolateral spine fusion model, the experimental study comprised 3 groups. Group 1 was composed of 6 animals that were implanted with 0.08 gram hydroxyapatite only. Group 2 was composed of 6 animals that were implanted with 0.08 gram hydroxyapatite containing 1 x 10(6)/ 60 microL rat of BMDMSCs. Group 3 was composed of 6 animals that were implanted with 0.08 gram hydroxyapatite containing 1 x 10(6)/ 60 microL of rat BMDMSCs and FGF-4 1 microG to induce the bony differentiation of the BMDMSCs. Rats were assessed using radiographs obtained at 4, 6, and 8 weeks postoperatively. After sacrifice, spines were explanted and assessed by manual palpation, high-resolution microcomputerized tomography, and histological analysis. RESULTS: Radiographic, high-resolution microcomputerized tomographic, and manual palpation revealed spinal fusion in five rats (83%) in Group 2 at 8 weeks. However, in Group 1, three (60%) rats developed fusion at L4-L5 by radiography and two (40%) by manual palpation in radiographic examination. In addition, in Group 3, bone fusion was observed in only 50% of rats by manual palpation and radiographic examination at this time. CONCLUSION: The present study demonstrates that 0.08 gram of hydroxyapatite with 1 x 10(6)/ 60 microL rat of BMDMSCs induced bone fusion. FGF-4, added to differentiate primitive 1 x 10(6)/ 60 microL rat of BMDMSCs did not induce fusion. Based on histologic data, FGF-4 appears to induce fibrotic change rather than differentiation to bone by 1 x 10(6)/ 60 microL rat of BMDMSCs.

Rhabdomyolysis following posterior lumbar interbody fusion in prone position: report 2 cases: Two cases report.

The spine surgery performed in the prone position could cause severe complications such as visual acuity impairment, spinal infarct and rhabdomyolysis. When treating rhabdomyolysis, it is important to prevent acute renal failure from accompanying rhabdomyolysis due to the poor prognosis. We have experienced two cases of rhabdomyolysis after spine surgery where dark urine was present during spine surgery under general anesthesia. Anesthesiologists should pay attention for early diagnosis and treatment of the rhabdomyolysis developing during the spine surgery.

Epidural tezampanel, an AMPA/kainate receptor antagonist, produces postoperative analgesia in rats.

BACKGROUND: We evaluated the epidural administration of tezampanel, a non-N-methyl-d-aspartate receptor antagonist, in a rat model for postoperative pain. We sought to determine if this drug affects nociception when administered epidurally by testing its effects on responses to heat in normal rats. The effects of epidural tezampanel on pain-related behaviors in rats that underwent plantar incision were also studied. METHODS: Rats were anesthetized and epidural catheters were placed. One day after epidural catheterization, the baseline heat withdrawal latency was measured. Epidural tezampanel or morphine was tested for analgesia by examining their effects against heat withdrawal latency. Motor function was also tested. Comparisons to subcutaneous drug administration were made. Other rats underwent plantar incision after epidural catheterization to assess pain behavior caused by incision. The effects of epidural tezampanel on the cumulative pain scoring, based on guarding, the withdrawal threshold to von Frey filament application, and the withdrawal latency to heat, were measured. The effects of epidural tezampanel on arterial blood pressure and heart rate were also tested. RESULTS: Both epidural morphine and epidural tezampanel increased withdrawal latency to heat. Only subcutaneous morphine affected heat withdrawal latency. After plantar incision, epidural tezampanel decreased the median guarding pain score, increased the heat withdrawal latency and increased the mechanical withdrawal threshold indicating analgesic effects. Arterial blood pressure and heart rate did not change after epidural drug administration. CONCLUSION: These experiments demonstrate that epidural administration of tezampanel produces analgesia to heat, motor side effects in some rats, and reduces pain behaviors caused by incision. No systemic analgesia was apparent using the largest dose.