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.

Relationship between first dorsal sacral foramen and lumbar facet joint connecting line in South Korea populations: Retrospective study.

The first sacral nerve root block (S1 nerve root block) is a practical procedure for patients with radiating lower back pain. In general, S1 nerve root block is performed under x-ray fluoroscopy. It is necessary to adjust the position of the patient and angle of fluoroscopy to properly visualize the first dorsal sacral foramen (dorsal S1 foramen). The purpose of this study was to analyze the location of dorsal S1 foramen and lumbar facet joint in S1 nerve root block.A total of 388 patients undergoing x-ray fluoroscopy-guided S1 nerve root block in the prone position were examined. X-ray fluoroscopy was fixed at the corresponding location of facet joint of L4-5 and L5-S1. The relationship of the connecting line vertical to L5-S1 facet joint and upper margin sacrum was evaluated. The surface anatomical relationships between dorsal S1 foramen and lumbar facet joint were assessed.Based on the localization of dorsal S1 foramen, the line drawn from point to upper margin sacrum passed through the dorsal S1 foramen in all cases. The horizontal distance from the spinous process to the dorsal S1 foramen was 25.9 ±â€Š3.0 mm for men and 26.2 ±â€Š1.4 mm for women. The horizontal distance from the between posterior superioriliac spine to the dorsal S1 foramen was 26.2 ±â€Š2.7 mm for men and 26.8 ±â€Š1.7 mm for women. The vertical distance from the upper margin of sacrum to dorsal S1 foramen to the dorsal S1 foramen was 45.6 ±â€Š6.5 mm for men and 43.8 ±â€Š6.0 mm for women.The connecting line vertical to L5-S1 facet joint and upper margin sacrum is located on the same line from the dorsal S1 foramen. For difficult cases of locating dorsal S1 foramen, the lumbar facet joint can assist in predicting the vertical location of the dorsal S1 foramen.

Transsacrococcygeal approach to ganglion impar block for treatment of chronic coccygodynia after spinal arachnoid cyst removal: A case report.

BACKGROUND: Coccygodynia is a pain in the region of the coccyx that radiates to the sacral, perineal area. The cause of the pain is often unknown. Coccygodynia is diagnosed through the patient's past history, a physical examination, and dynamic radiographic study, but the injection of local anesthetics or a diagnostic nerve blockade are needed to distinguish between somatic, neuropathic, and combined pain. Ganglion impar is a single retroperitoneal structure made of both paravertebral sympathetic ganglions. Although there are no standard guidelines for the treatment of coccygodynia, ganglion impar blockade is one of the effective options for treatment. METHODS: Here, we report a 42-year-old female patient presenting with severe pain in the coccygeal area after spinal arachnoid cyst removal. RESULTS: Treatment involved neurolysis with absolute alcohol on the ganglion impar through the transsacrococcygeal junction. Pain was relieved without any complications. CONCLUSION: Our case report offers the ganglion impar blockade using the transsacrococcygeal approach with absolute alcohol can improve intractable coccydynia.

Effect of bevel direction on the success rate of ultrasound-guided radial arterial catheterization.

BACKGROUND: This study assessed the effect of bevel direction on the success rate of ultrasound guided radial artery catheterization. METHODS: A total of 204 patients requiring radial artery catheterization were randomly divided into bevel-up (n = 102) and bevel-down (n = 102) groups. Success rate, cannulation time, and number of attempts were compared groups. RESULTS: In the bevel-down group, an arterial line was placed on the first attempt in 86 of 102 (84.3 %; 95 % confidence interval [CI] = 76 % to 90 %) patients versus 73 of 102 (71.6 %; 95 % CI = 62.1 % to 79.4 %) in the bevel-up group (p = 0.028). In the bevel-down group, the mean time to a successful radial arterial cannulation was 33.3 ± 6.3 seconds (95 % CI = 32.1-34.6) versus 35.9 ± 7.6 seconds (95 % CI = 34.4-37.2) in the bevel-up group (p = 0.011). The median score was 33.2 and interquartile range [IQR] was 10.9 (30.3-41.2) for the mean cannulation time in the bevel-up group. In the bevel-down group, the mean score was 32.3 (IQR 3.90, 30-33.9) for mean cannulation time. In the bevel-down group, 11 of 102 (7 %; 95 % CI = 0 to 16 %) patients developed a posterior wall puncture versus 22 of 102 ((21.6 %; 95 % CI = 14.7 to 17.2 %) in the bevel-up group. CONCLUSION: The bevel-down approach during ultrasound-guided radial artery catheterization exhibited a higher success with fewer complications compared to the bevel-up approach. TRIAL REGISTRATION: Clinical Research Information Service is Korean Clinical Trials Registry ( KCT0001836 ). It was registered retrospectively 30th Nov 2015.

A comparison of posterior and medial cord stimulation for neurostimulation-guided vertical infraclavicular block: a randomized noninferiority clinical trial.

BACKGROUND: We investigated whether medial cord stimulation is inferior to posterior cord stimulation for vertical infraclavicular block with respect to block success. METHODS: Ninety-six patients scheduled for upper limb surgery were randomly elicited a medial or posterior cord response for infraclavicular block using 40 mL of 0.5% ropivacaine. We assessed block success (complete sensory block of the 5 nerves in the forearm at 50 minutes) as the primary end point and block procedure characteristics and adverse events as secondary end points. RESULTS: The block success rates did not differ significantly between medial and posterior cord stimulation (95.7% [44/46] vs 91.7% [44/48], 95% CI of difference, -7.4% to 15.6%), while the secondary end points were comparable in both groups. CONCLUSIONS: Needle manipulation to elicit medial cord response is noninferior to posterior cord response of block success during neurostimulation-guided vertical infraclavicular block.

Transient hemidiaphragmatic paresis after ultrasound-guided lateral sagittal infraclavicular block.

As compared with medial approaches for the infraclavicular brachial plexus block, lateral approaches generally have no impact on the phrenic nerve or pulmonary function. A patient experienced transient hemidiaphragmatic paresis after ultrasound-guided lateral sagittal infraclavicular block for lower arm surgery. An accessory phrenic nerve, ie, an anatomical variation, may have been the mechanism of transient hemidiaphragmatic paresis in this patient.

A randomized comparison of ropivacaine 0.1% and 0.2% for continuous interscalene block after shoulder surgery.

BACKGROUND: The optimal concentration of ropivacaine for continuous interscalene block after shoulder surgery is currently unknown. METHODS: Fifty-six patients received a perineural infusion of either ropivacaine 0.1% or 0.2% for 48 hours after shoulder surgery. We assessed pain scores as primary end points and supplemental analgesia, ropivacaine consumption, motor block, side effects, and patient satisfaction as secondary end points. RESULTS: Pain scores were not statistically different during the infusion periods; however, supplemental analgesia consumption was higher in the group receiving ropivacaine 0.1% during the first 24 hours (64% vs 28%, P = 0.022). Other secondary end points were statistically inconclusive. CONCLUSIONS: These results suggest that ropivacaine 0.2% provides more effective analgesia than ropivacaine 0.1% during the first 24 hours for continuous interscalene block after shoulder surgery.

Transient right hemidiaphragmatic paralysis following subclavian venous catheterization: possible implications of anatomical variation of the phrenic nerve -a case report-.

Phrenic nerve paralysis is an unusual complication associated with central venous catheterization. Various mechanisms have been proposed. We present a case of transient right hemidiaphragmatic paralysis after subclavian venous catheterization. We hypothesize that anatomical variation of the phrenic nerve was responsible for this complication.

Effects of increasing the dose of ropivacaine on vertical infraclavicular block using neurostimulation.

BACKGROUND: Use of an infraclavicular block is appropriate for surgery of the upper limb. However, it does not consistently block the entire brachial plexus. The aim of this study was to investigate whether increasing the dose of ropivacaine could enhance the success rate, onset time, and efficacy of the sensory and motor block during the use of a vertical infraclavicular block using neurostimulation in upper limb surgery. METHODS: TWO HUNDREDS AND TEN PATIENTS WERE PROSPECTIVELY RANDOMIZED INTO THREE GROUPS: Group 1 (30 ml of 0.5% ropivacaine; n = 70), Group 2 (40 ml of 0.5% ropivacaine; n = 70), and Group 3 (40 ml of 0.75% ropivacaine; n = 70). Patients in each group received a vertical infraclavicular block using neurostimulation and obtained a distal motor response of the ulnar or median nerve. Recorded outcome measures included block success rate, onset time, sensory and motor blocks, and adverse events. RESULTS: No differences were found in the block success rate among the three groups (92.8%, 97.1%, and 94.2% for Groups 1, 2, and, 3, respectively; P = 0.346). There were no significant differences in onset time (P = 0.225) among groups, nor was there enhancement in the sensory block, but the motor block was enhanced. Local anesthetic toxicity was observed in five female patients from group 3 (P = 0.006). CONCLUSIONS: Although the efficacy of the motor block was significantly improved, success rate, onset time, and efficacy of sensory block were not enhanced significantly among groups despite differences in volume and volume/concentration of the local anesthetic.

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.

A comparison of infraclavicular and supraclavicular approaches to the brachial plexus using neurostimulation.

BACKGROUND: A prospective, double blind study was performed to compare the clinical effect of vertical infraclavicular and supraclavicular brachial plexus block using a nerve stimulator for upper limb surgery. METHODS: One hundred patients receiving upper limb surgery under infraclavicular or supraclavicular brachial plexus block were enrolled in this study. The infraclavicular brachial plexus block was performed using the vertical technique with 30 ml of 0.5% ropivacaine. The supraclavicular brachial plexus block was performed using the plumb bob technique with 30 ml of 0.5% ropivacaine. The block performance-related pain was evaluated. This study observed which nerve type was stimulated, and scored the sensory and motor block. The quality of the block was assessed intra-operatively. The duration of the sensory and motor block as well as the complications were assessed. The patient's satisfaction with the anesthetic technique was assessed after surgery. RESULTS: There were no significant differences in the block performance-related pain, frequency of the stimulated nerve type, evolution of sensory and motor block quality, or the success of the block. There were no significant differences in the duration of the sensory and motor block. There was a significant difference in the incidence of Horner's syndrome. Two patients had a pneumothorax in the supraclavicular approach. There were no significant differences in the patient's satisfaction. CONCLUSIONS: Both infraclavicular and supraclavicular brachial plexus block had similar effects. The infraclavicular approach may be preferred to the supraclavicular approach when considering the complications.

Pleural effusion and atelectasis during continuous interscalene brachial plexus block -A case report-.

An interscalene brachial plexus block is an effective means of providing anesthesia-analgesia for shoulder surgery. However, it has a multitude of potential side effects such as phrenic nerve block. We report a case of a patient who developed atelectasis of the lung, and pleural effusion manifested as chest discomfort during a continuous interscalene brachial plexus block for postoperative analgesia.

Acute hypertensive pulmonary edema after Cesarean section in a patient with an antepartum myocardial infarction -A case report-.

We report a case of 29-year-old, morbidly obese, diabetic primigravida who had undergone previously primary percutaneous coronary intervention with stent placement for an inferior wall myocardial infarction at 10 weeks of gestation. She remained asymptomatic with medication during the remainder of her pregnancy, but preoperative echocardiography revealed left ventricular dilation and a restrictive diastolic dysfunction with a preserved ejection fraction (46%). She developed acute pulmonary edema associated with hypertension after an elective Cesarean delivery under continuous epidural anesthesia despite the meticulous restriction of fluid.

Ultrasound-guided supraclavicular brachial plexus block in pediatric patients -A report of four cases-.

Supraclavicular brachial plexus blocks are not common in pediatric patients due to the risk of pneumothorax. Ultrasonography is an important tool for identifying nerves during regional anesthesia. Directly visualizing the target nerves and monitoring the distribution of the local anesthetic are potentially significant. In addition, ultrasound monitoring helps avoid complications, such as inadvertent intravascular injection or pneumothorax. This paper reports four cases of pediatric patients who received ultrasound-guided supraclavicular brachial plexus block for upper limb surgery.

Continuous epidural analgesia versus continuous intravenous analgesia with peri-articular infiltration following total knee arthroplasty in geriatric patients.

BACKGROUND: Postoperative continuous intravenous analgesia may not provide effective postoperative analgesia following total knee arthroplasty. This study was conducted to determine if combined continuous intravenous analgesia and peri-articular infiltration provided a better quality of analgesia following total knee arthroplasty than epidural analgesia. METHODS: A prospective, double-blind study involving 50 patients who had undergone total knee arthroplasty was conducted. Patients were divided into control group and an experimental group. Patients in the control group (n = 25) received peri-articular infiltration with 47 mL normal saline prior to closure of the wound and postoperative epidural analgesia for 48 hours. Patients in the experimental group (n = 25) received a mixture of peri-articular infiltration of 16 mL of 0.75% ropivacaine, 6 mg morphine, 0.2 mg of epinephrine and 25 mL normal saline prior to closure of the wound and postoperative continuous intravenous analgesia for 48 hours. The analgesic efficacy was then evaluated using the verbal numeric rating scale at 1, 2, 6, 12, 24, and 48 hours postoperatively. The side effects and the dosage of rescue analgesics were then recorded. RESULTS: The experimental group showed a significantly higher pain score than the control group 2 and, 6 hours postoperatively at rest and 2 hours postoperatively following passive knee movement (P < 0.05). In addition, the rescue analgesic requirement was higher for the experimental group during the first 24 hours following surgery than for the control group (P < 0.05). CONCLUSIONS: We found that combined continuous intravenous analgesia and peri-articular infiltration of a mixture of ropivacaine and, morphine injected into the peri-articular tissue provided minimal benefits for pain control during the early postoperative period when compared to epidural analgesia after total knee arthroplasty.

Comparison of vertical infraclavicular brachial plexus block with 0.5% levobupivacaine and 0.5% ropivacaine for upper limb surgery.

BACKGROUND: We performed a prospective, double blind study to compare the clinical effect of vertical infraclavicular brachial plexus block produced by 0.5% levobupivacaine and 0.5% ropivacaine for upper limb surgery. METHODS: We included 60 patients receiving upper limb surgery under infraclavicular brachial plexus block. The infraclavicular brachial plexus block was performed via the vertical technique with 30 ml of 0.5% levobupivacaine or 0.5% ropivacaine. We observed which nerve type was stimulated and scored the sensory and motor block. The quality of block was assessed intraoperatively. The duration of sensory and motor block and complications were assessed. RESULTS: There were no significant differences in frequencies of stimulated nerve type, evolution of sensory and motor block quality, or success of block. There were no significant difference in duration of sensory block, but duration of motor block was prolonged after 0.5% levobupivacaine. There were no complications. CONCLUSIONS: Both 0.5% levobupivacaine and 0.5% ropivacaine had similar effects in the vertical infraclavicular brachial plexus block.

A clinical comparison of vertical infraclavicular brachial plexus block using 0.75% or 0.5% ropivacaine for upper limb surgery.

BACKGROUND: We performed a prospective, double blind study to compare the clinical effect of vertical infraclavicular brachial plexus block produced by 0.75% vs 0.5% ropivacaine for upper limb surgery. METHODS: We included 80 patients receiving upper limb surgery under infraclavicular brachial plexus block. The infraclavicular brachial plexus block was performed via the vertical technique with 30 ml of 0.75% or 0.5% ropivacaine. By observation, we determined nerve type was stimulated and scored the level of sensory block and motor block. The quality of blocks was assessed intra-operatively. The duration of sensory block and motor block and their complications were assessed. RESULTS: There were no significant differences in the frequency of stimulated nerve type, evolution of sensory and motor block quality, or success of block. There were no significant differences in the duration of sensory block and motor block. Vascular puncture was noted in 1 patient in the 0.75% ropivacaine. CONCLUSIONS: Both the 0.75% and 0.5% ropivacaine had similar effects in the vertical infraclavicular brachial plexus block.