Effect of Remimazolam- versus Propofol-Based Total Intravenous General Anesthesia on Intraoperative Hemodynamic Stability for Major Spine Surgery in the Prone Position: A Randomized Controlled Trial.

Background and Objectives: Remimazolam offers advantages over propofol in terms of hemodynamic stability. However, it remains unclear whether remimazolam-based total intravenous anesthesia (TIVA) can reduce intraoperative hypotension compared to propofol-based TIVA, especially after prone positioning. In this study, we compared the effects of remimazolam- and propofol-based TIVA on intraoperative hemodynamic stability in patients undergoing surgery in the prone position. Materials and Methods: This study randomly assigned patients undergoing major spinal surgery in the prone position to the propofol or remimazolam group. Target-controlled infusion (2-3.5 µg/mL for induction and 2-3 µg/mL for maintenance) was used in the propofol group and continuous infusion (6 mg/kg/h for induction and 1-2 mg/kg/h for maintenance) was used in the remimazolam group; target-controlled infusion (3-5 ng/mL) of remifentanil was performed in both groups. The primary outcomes were the incidence of hypotensive episodes during the first hour after prone positioning. The secondary outcomes included the incidence of severe hypotension and the total amount of inotropic or vasopressor medication. Systolic and mean arterial pressure, heart rate, cardiac index and output, stroke volume, stroke volume variation, and pleth variability index were also evaluated. These variables were recorded per minute for the first 10 min after prone positioning, and every 10 min thereafter. Results: The study enrolled 94 patients (47 patients in each group). The incidence of hypotension or severe hypotension did not differ significantly between the two groups during the first hour after prone positioning. The total amount of ephedrine administered during the first hour after prone positioning was lesser (p = 0.020) and the mean arterial pressure during the initial 10 min after prone positioning was higher in the remimazolam group (p = 0.003). Conclusions: Our study uncovered no significant differences in the incidence of hypotension between remimazolam- and propofol-based TIVA in patients undergoing major spine surgery in prone position.

Evaluating the Clinical Utility of Brachial Plexus Block for Reducing Opioid Exposure in Pediatric Elbow Fracture Surgery: A Retrospective Cohort Study.

Background and Objectives: Reducing opioid exposure in common pediatric surgeries is of paramount importance. This study aimed to assess the efficacy of regional nerve blocks in reducing opioid exposure while preserving high success rates. Materials and Methods: We conducted a retrospective matched cohort study (1:1) including patients with elbow fractures < 12 years old who underwent treatment with percutaneous pinning. Patients were divided into general-anesthesia (GA) and GA-followed-by-supraclavicular-brachial-plexus-block (GA-SCB) groups. The primary outcome was the number of patients administered postoperative rescue opioids. The secondary outcomes included intraoperative and postoperative opioid administration, the time to first request for rescue analgesia, pain scores, block success rate, block performing time, and block-related complications. Results: In a total of 478 patients, 363 underwent percutaneous pinning, and 86 were cohort-matched (GA: n = 43, GA-SCB: n = 43). On the first postoperative day, 34 (79.0%) patients in the GA group were administered postoperative rescue opioids, compared with 12 (27.9%) in the GA-SCB group (p < 0.001). All the patients in the GA-SCB group were opioid-free during the intraoperative period. No SCB-associated complications were observed. Total opioid consumption was significantly lower in the GA-SCB group than in the GA group until the first postoperative day (GA vs. GA-SCB, 3.2 ± 3.0 mg vs. 0.9 ± 1.8 mg, p < 0.001). Conclusions: SCB application in pediatric patients who underwent elbow fracture surgery significantly reduced opioid exposure and had a high success rate when performed using ultrasound guidance by an expert. Furthermore, the complication risk and surgical delay were minimal.

Effective remimazolam loading dose for adequate sedation in regional anesthesia.

PURPOSE: Remimazolam is a novel ultrashort-acting sedative considered appropriate for continuous infusion during surgical procedures. Nevertheless, information regarding its loading dose for sedation during surgery is limited. We aimed to determine the 90% effective dose (ED90) of the remimazolam loading dose for sedation in patients undergoing limb surgery under regional anesthesia. METHODS: We included 50 patients aged 19-80 yr undergoing limb surgery under regional anesthesia. After regional anesthesia, remimazolam besylate was administered at the assigned dose. For ten minutes after the initiation of loading, the level of sedation was evaluated using the Modified Observer's Assessment of Alertness/Sedation (MOAA/S) scale. The primary outcome was the ED90 based on whether patients reached a MOAA/S score of ≤ 3 points (loss of response to verbal command) within ten minutes. The secondary outcomes were the ED50 and the estimated effect site and plasma concentration at the time of achieving successful sedation. RESULTS: In total, 49 patients were included in the final analysis, and adequate sedation with the assigned loading dose was successful in 42 patients. The log-logistic function showed that the ED90 and ED50 were 0.617 mg·kg-1·hr-1 (95% confidence interval [CI], 0.511 to 0.722; 98% CI, 0.492 to 0.741) and 0.438 mg·kg-1·hr-1 (95% CI, 0.335 to 0.541; 98% CI, 0.315 to 0.560), respectively. CONCLUSION: The ED90 of the remimazolam loading dose to achieve adequate sedation in patients undergoing limb surgery under regional anesthesia was 0.617 mg·kg-1·hr-1 (95% CI, 0.511 to 0.722; 98% CI, 0.492 to 0.741). STUDY REGISTRATION: ClinicalTrials.gov (NCT05340335); first posted 22 April 2022.

RéSUMé: OBJECTIF: Le remimazolam est un nouveau sédatif à action ultracourte considéré comme approprié pour la perfusion continue pendant les interventions chirurgicales. Néanmoins, les informations concernant sa dose de charge pour la sédation pendant la chirurgie sont limitées. Notre objectif était de déterminer la dose efficace à 90 % (DE90) de la dose de charge de remimazolam pour la sédation chez la patientèle bénéficiant d'une chirurgie d'un membre sous anesthésie régionale. MéTHODE: Cinquante personnes âgées de 19 à 80 ans bénéficiant d'une chirurgie des membres sous anesthésie régionale ont été incluses. Après l'anesthésie régionale, du bésylate de remimazolam a été administré à la dose assignée. Pendant dix minutes après le début de la charge, le niveau de sédation a été évalué à l'aide de l'échelle modifiée d'évaluation de la vigilance/sédation par l'observateur (MOAA/S). Le critère d'évaluation principal était la DE90 selon que les patient·es ont atteint un score MOAA/S de ≤ 3 points (perte de réponse à la commande verbale) dans les dix minutes. Les critères d'évaluation secondaires étaient la DE50 et l'estimation du site d'effet et de la concentration plasmatique au moment de l'obtention d'une sédation réussie. RéSULTATS: Au total, 49 personnes ont été incluses dans l'analyse finale, et une sédation adéquate avec la dose de charge assignée a été couronnée de succès chez 42 d'entre elles. La fonction log-logistique a montré que les DE90 et DE50 étaient de 0,617 mg·kg−1·h−1 (intervalle de confiance [IC] à 95 %, 0,511 à 0,722; IC 98 %, 0,492 à 0,741) et 0,438 mg·kg−1·h−1 (IC 95 %, 0,335 à 0,541; IC 98 %, 0,315 à 0,560), respectivement. CONCLUSION: La DE90 de la dose de charge de remimazolam pour obtenir une sédation adéquate chez les personnes bénéficiant d'une chirurgie des membres sous anesthésie régionale était de 0,617 mg·kg−1·h−1 (IC 95 %, 0,511 à 0,722; IC 98 %, 0,492 à 0,741). ENREGISTREMENT DE L'éTUDE: ClinicalTrials.gov (NCT05340335); première publication le 22 avril 2022.

Comparison of preemptive and preventive intravenous acetaminophen on opioid consumption in pediatrics undergoing posterior spinal fusion surgery: a randomized controlled trial.

Background: Posterior spinal fusion (PSF), commonly used for adolescent idiopathic scoliosis (AIS), causes severe postoperative pain. Intravenous (IV) administration of acetaminophen has shown promise for opioid-sparing analgesia; however, its analgesic effect and optimal timing for its standard use remain unclear. Our study aimed to evaluate the analgesic effect and optimal timing of IV acetaminophen administration in pediatric and adolescent patients undergoing PSF and requiring adequate pain control. Methods: This prospective, randomized, triple-blind trial was conducted in patients aged 11-20 undergoing PSF. Participants were randomized into three groups: the preemptive group (received IV acetaminophen 15 mg/kg after anesthetic induction/before surgical incision), the preventive group (received IV acetaminophen 15 mg/kg at the end of surgery/before skin closure), and the placebo group. The primary outcome was cumulative opioid consumption during the first 24 h postoperatively. Results: Among the 99 enrolled patients, the mean ± standard deviation (SD) amount of opioid consumption during the postoperative 24 h was 60.66 ± 23.84, 52.23 ± 22.43, and 66.70 ± 23.01 mg in the preemptive, preventive, and placebo groups, respectively (overall p = 0.043). A post hoc analysis revealed that the preventive group had significantly lower opioid consumption than the placebo group (p = 0.013). However, no significant differences between the groups were observed for the secondary outcomes. Conclusions: The preventive administration of scheduled IV acetaminophen reduces cumulative opioid consumption without increasing the incidence of drug-induced adverse events in pediatric and adolescent patients undergoing PSF.

The impact of inappropriate steroid exposure before the diagnosis of Kawasaki disease.

BACKGROUND: Kawasaki disease (KD) is a systemic inflammatory disease characterized by vasculitis. In South Korea, some pediatric doctors empirically prescribe steroids to control febrile pediatric patients. This study aimed to evaluate the clinical characteristics of patients with KD after steroid exposure. METHODS: This was a single-center, retrospective, observational study. This study included patients (aged ≤15 years) between January 2020 and July 2022. We compared two groups, one group exposed to steroids and the other group who were not, using the Student's t-test or analysis of variance; otherwise, the Mann-Whitney U test or Kruskal-Wallis test was conducted. Statistical significance was set at p < 0.05. RESULTS: In total, 190 patients with KD were enrolled; of these, 64 (33.7 %) had a history of steroid exposure, and 126 (66.3 %) had no history of steroid exposure. In the steroid exposure group, prolonged fever duration (6.72 ± 1.72 versus 5.61 ± 1.19, p-value = <0.001), a lower proportion of complete KD (29.69 % vs. 88.10 %, p-value = <0.001), and a significantly lower level of C-reactive protein were observed. However, no significant correlations were observed between the Transthoracic Echocardiography (TTE) results (coronary artery aneurysm, existence of pericardial effusion) and prognostic factors (days of hospitalization, the number of intravenous immunoglobulin administrations, and Kobayashi score) between the two groups. CONCLUSIONS: Patients with KD and previous steroid exposure may exhibit an incomplete KD phenotype with prolonged fever. Although previous steroid exposure does not affect the prognosis of KD, including coronary artery aneurysms, it may mask the classic features of KD, resulting in a delayed diagnosis.

Right lower lung midline herniation as a rare complication in an infant with heart-lung transplantation: A case report.

BACKGROUND: Lung herniation is a rare complication of heart-lung transplantation that can be fatal owing to vascular compromise and airway obstruction. To date, only five cases of lung herniation related to heart-lung transplantation have been reported in the literature; however, to the best of our knowledge, this is the first worldwide report of heart-lung transplantation-related lung herniation in an infant. METHODS: We describe the case of lung herniation as a rare heart-lung transplantation-related complication in an infant. A 12-month-old female baby developed severe bronchopulmonary dysplasia with severe pulmonary hypertension, and she underwent extracorporeal membrane oxygenation for cardiac collapse and lung support. Then, we performed heart-lung transplantation to manage the irreversible deterioration of her lung function. After the heart-lung transplantation, we found the radiological abnormalities persisted on follow-up chest radiographs until the 13th postoperative day diagnosed as lung herniation of the right lower lobe on chest computed tomography. RESULTS: After the relocation of the herniated lung, the clinical condition of the patient improved, and the patient is currently growing without any respiratory symptoms. CONCLUSIONS: In this case report, we emphasize that clinical awareness and high suspicion of this rare complication are needed for early diagnosis and proper treatment to prevent post-transplantation morbidity and mortality related to potential ischemic injury.

Comparison of international medical costs for interventional pain treatment: a focus on Korea and Japan.

Background: The rise in national health care costs has emerged as a global problem given the ever-aging population and rapid development of medical technology. The utilization of interventional pain management has, similarly, shown a continued rise worldwide. This study evaluates the differences in the medical costs in the field of interventional pain treatment (IPT) between two countries: Korea and Japan. Methods: Korean medical insurance costs for 2019 related to pain management focused on IPT were compared to those of Japan. Purchasing power parity (PPP) was used to adjust the exchange rate differences and to compare prices in consideration of the respective societies' economic power. Results: The cost of trigger point injections in Japan was 1.06 times higher than that of Korea, whereas the perineural and intraarticular injection prices were lower in Japan. The cost of epidural blocks was higher in Japan compared to Korea in both cervical/thoracic and lumbar regions. As for blocks of peripheral branches of spinal nerves, the cost of scapular nerve blocks in Japan was lower than that in Korea, given a PPP ratio 0.09. For nerve blocks in which fluoroscopy guidance is mandatory, the costs of epidurography in Japan were greater than those in Korea, given a PPP ratio 1.04. Conclusions: This is the first comparative study focusing on the medical costs related to IPT between Korea and Japan, which reveals that the costs differed along various categories. Further comparisons reflecting more diverse countries and socio-economic aspects will be required.

Effect of Operating Conditions on the Gasification of Pet-Coke Water Slurry in an Entrained-Flow Gasifier Simulation.

Petroleum coke, commonly known as pet-coke, represents a promising and cost-effective alternative fuel source, produced as a byproduct of large-scale heavy crude oil refining. This study first simulated the gasification process of pet-coke slurry using a three-dimensional computational fluid dynamics (CFD) approach based on the Eulerian-Lagrangian method. The simulation was carried out in a 2-ton-per-day (2TPD) entrained-flow gasifier, aiming to optimize the production of hydrogen (H2) and carbon monoxide (CO) as synthetic gases. This study investigated the effects of operational parameters, including the oxygen/slurry ratio and moisture content in the slurry, on various aspects such as fluid dynamics, temperature distribution, particle trajectories, carbon conversion, and gas composition within the pet-coke slurry gasifier. The base conditions of the simulation were meticulously cross-validated with high-precision experimental data. The results indicated that higher oxygen/slurry ratios led to increased concentrations of carbon dioxide (CO2) and decreased fractions of H2, primarily due to the prevalence of the reverse water-gas shift reaction. Moreover, raising the moisture content in the pet-coke slurry led to decreased CO levels and enhanced production of H2 and CO2, triggered by the activation of the forward water-gas shift reaction. These results underscore the potential of pet-coke slurry as a favorable feedstock for syngas production and the achievement of carbon neutrality through the careful optimization of operational conditions. Our findings provide valuable insights for further experimental exploration and the development of practical applications for pet-coke gasification.

A comparison of the continuous supraclavicular brachial plexus block using the proximal longitudinal oblique approach and the interscalene brachial plexus block for arthroscopic shoulder surgery: A randomised, controlled, double-blind trial.

BACKGROUND: Continuous interscalene brachial plexus block (ISB) is widely used for arthroscopic shoulder surgery, but the incidence of hemidiaphragmatic paresis (HDP) has been reported to reach 100%. Several methods, including injections distal to the C5-C6 nerve roots, have been attempted to reduce the HDP incidence. However, catheter placement distal to the C5-C6 nerve roots interferes with the surgical site. OBJECTIVE: Our primary objective was to describe a new technique, the supraclavicular brachial plexus block (SCB), using the proximal longitudinal oblique approach (PLO-SCB), which can facilitate catheter placement and, when compared with ISB, to test whether this would provide noninferior analgesia and spare the phrenic nerve. DESIGN: Prospective, randomised, double-blind study. SETTING: Operating rooms, postanaesthesia care unit, and wards. PATIENTS: Seventy-six patients aged 20 to 80 years scheduled for arthroscopic shoulder surgery. INTERVENTIONS: Patients were randomly assigned to the continuous PLO-SCB (n = 40) or the continuous ISB (n = 40) groups. All patients received an initial low-volume single-injection (5 ml 0.75% ropivacaine) followed by a patient-controlled infusion of 0.15% ropivacaine. MAIN OUTCOME MEASURES: The primary outcomes were the incidence of HDP and pain scores. Secondary outcomes were respiratory function, postoperative analgesic consumption, sensory and motor function, and complications. RESULTS: The HDP incidence was significantly lower in the PLO-SCB group than in the ISB group at 30 min after block injection: 0% (0 of 38 patients) and 73.7% (28 of 38 patients), respectively (P < 0.001). Similarly, at 24 h after surgery, the incidences were 23.7% (9 of 38 patients) and 47.4% (18 of 38 patients) in the PLO-SCB and ISB groups, respectively (P = 0.002). Median [IQR] NRS pain scores at rest measured after surgery in the ISB and PLO-SCB groups were similar: immediately after surgery, 1 [0 to 2] vs. 1 [0 to 1], P = 0.06); at 30 min, 2 [0.25 to 2] vs. 1 [0 to 2], P = 0.065); and at 24 h 2 [0.25 to 3] vs. 1 [0 to 3], P = 0.47, respectively. CONCLUSION: For major shoulder surgery, compared with continuous ISB, continuous PLO-SCB was more sparing of diaphragmatic and respiratory function while providing noninferior analgesia. Catheter placement via the PLO approach is feasible without interfering with the surgical field. TRIAL REGISTRATION: Registered by the Clinical Trial Registry of Korea (Seoul, Korea; KCT0004759, http: cris.nih.go.kr, principal investigator: Hyungtae Kim).

Postoperative Valgus Deformity and Progression of Ostheoarthritis in Non-Displaced Femoral Neck Fractures.

Purpose: Nondisplaced femoral neck fractures have traditionally been treated with in situ fixation. However, poor surgical and clinical outcomes have been reported for fractures with valgus deformity >15°, and the reduction of valgus impaction has recently been emphasized. In addition, early degenerative osteoarthritis can be caused by cam-type femoroacetabular impingement after healing of femoral neck fractures. This study was designed with the objective of confirming the difference in progression of radiographic osteoarthritis according to the severity of the valgus deformity. Materials and Methods: Patients who underwent internal fixation using multiple cannulateld screws for management of nondisplaced femoral neck fractures were divided into two groups: high valgus group (postoperative valgus angle ≥15°) and low valgus group (postoperative valgus angle <15°). Evaluation of demographic data and changes in the joint space width from the immediate postoperative period to the latest follow-up was performed. Results: A significant decrease in joint space width in both hip joints was observed in the high valgus group when compared with the low valgus group, including cases with an initial valgus angle less than 15° and those corrected to less than 15° of valgus by reduction. No complications requiring surgical treatment were observed in either group; however, two cases of avascular necrosis, one in each group, which developed in the low valgus group after reduction of the fracture, were followed for observation. Conclusion: Performing in situ fixation in cases involving a valgus deformity ≥15° in non-displaced femoral neck fractures may cause accelerated narrowing of the hip joint space.

Erratum: Correction of Affiliation in the Article "Growth Pattern of the Neo-Aorta after Arterial Switch Operation: What Is the Factor of Determination?"

This corrects the article on p. 94 in vol. 51, PMID: 33377331.

Norepinephrine prevents hypotension in older patients under spinal anesthesia with intravenous propofol sedation: a randomized controlled trial.

Reducing hypotension is crucial as hypotension is the most common side effect of spinal anesthesia, and in older patients with various comorbidities, it can lead to fatality. We hypothesized that continuous infusion of norepinephrine could effectively prevent hypotension in older patients undergoing hip surgery under spinal anesthesia with propofol sedation. The study randomly assigned patients aged ≥ 70 years to either a control (Group C, n = 35) or a norepinephrine group (Group N, n = 35). After spinal anesthesia, continuous infusion of propofol and normal saline or norepinephrine was initiated. The number of hypotensive episodes, the primary outcome, as well as other intraoperative hemodynamic events and postoperative complications were compared. In total, 67 patients were included in the final analysis. The number of hypotensive episodes was significantly higher in Group C than in Group N (p < 0.001). Furthermore, Group C required a greater amount of fluid to maintain normovolemia (p = 0.008) and showed less urine output (p = 0.019). However, there was no difference in postoperative complications between the two groups. Continuous intravenous infusion of prophylactic norepinephrine prevented hypotensive episodes, reduced the requirement of fluid, and increased the urine output in older patients undergoing unilateral hip surgery under spinal anesthesia with propofol sedation.Clinical trial registration number: KCT0005046 ( https://cris.nih.go.kr ). IRB number: 2020-0533 (Institutional Review Board of Asan Medical Center, approval date: 13/APR/2020).

Comparison of the Analgesic Efficacy between Arthroscopically Placed Continuous Suprascapular Nerve Block and Ultrasound-guided Continuous Superior Trunk Block: A Double-blinded Randomized Controlled Trial.

BACKGROUND: Single-shot suprascapular nerve block and superior trunk block have been reported to provide a noninferior analgesic effect after shoulder surgery with a lesser incidence of hemidiaphragmatic paresis compared with interscalene brachial plexus block. This study hypothesized that continuous suprascapular nerve block provides noninferior analgesia with minimal effects on diaphragmatic movement compared with continuous superior trunk block in patients undergoing arthroscopic shoulder surgery. METHODS: 100 patients were randomized undergoing arthroscopic shoulder surgery between December 2020 and October 2021 into continuous suprascapular nerve block and continuous superior trunk block groups. Before the surgery, patients received either a single-shot superior trunk block or subomohyoid suprascapular nerve block. Thereafter, a superior trunk catheter was inserted by anesthesiologists in patients in the continuous superior trunk block group, and a posterior suprascapular nerve catheter was inserted with arthroscopic assistance during the surgery by surgeon in the continuous suprascapular nerve block group. The primary outcome was the postoperative pain score at postoperative 24 h, and the incidence of hemidiaphragmatic paresis was also compared. RESULTS: Overall, 98 patients were included in the final analysis. The worst and resting pain scores at postoperative 24 h in the continuous suprascapular nerve block group were inferior compared with those in the continuous superior trunk block group in the test with a noninferiority margin of 1 (worst pain score: mean difference, 0.9; 95% CI, 0.1 to 1.7; resting pain score: mean difference, 0.5; 95% CI, 0.0 to 1.0). However, the continuous suprascapular nerve block group had a significantly lower incidence of hemidiaphragmatic paresis at postoperative 24 h than the continuous superior trunk block group. CONCLUSIONS: Continuous suprascapular nerve block provides statistically inferior analgesia compared to the continuous superior trunk block; however, the continuous suprascapular nerve block had a minimal effect on the phrenic nerve function.

Comparison of a Peripheral Nerve Block versus Spinal Anesthesia in Foot or Ankle Surgery: A Systematic Review and Meta-Analysis with a Trial Sequential Analysis.

Background: This systematic review and meta-analysis with trial sequential analysis (TSA) aimed to compare perioperative outcomes of peripheral nerve blocks (PNBs) and spinal anesthesia (SA) in elective foot and ankle surgery. Methods: The study protocol was registered in PROSPERO (CRD42021229597). Researchers independently searched PubMed, EMBASE, and the Cochrane Central Register of Controlled Trials for relevant randomized controlled trials (RCTs). Results: Analysis of nine RCTs (n = 802; 399 PNBs, 403 SA) revealed significantly shorter block performance times (WMD: 7.470; 95% CI 6.072 to 8.868), the onset of sensory (WMD: 7.483; 95% CI 2.837 to 12.130) and motor blocks (WMD: 9.071; 95% CI 4.049 to 14.094), durations of sensory (WMD: 458.53; 95% CI 328.296 to 588.765) and motor blocks (WMD: 247.416; 95% CI 95.625 to 399.208), and significantly higher postoperative analgesic requirements (SMD: -1.091; 95% CI -1.634 to -0.549) in the SA group. Additionally, systolic blood pressure (SBP) at 30 min (WMD: 13.950; 95% CI 4.603 to 23.298) was lower in the SA group. Conclusions: The SA demonstrated shorter block performance time, faster onset and shorter duration of sensory and motor blocks, higher postoperative analgesic requirements, and lower SBP at 30 min compared to PNBs in elective foot and ankle surgery.

Prevalence of and factors associated with stenotic thoracic ligamentum flavum hypertrophy.

INTRODUCTION: Stenotic thoracic ligamentum flavum hypertrophy can cause leg and/or low back pain similar to that caused by lumbar spinal stenosis. However, the thoracic spine may occasionally be overlooked in patients with leg and/or low back pain. An accurate understanding of the prevalence of stenotic thoracic ligamentum flavum hypertrophy and its associated factors is necessary. METHODS: In this prevalence study, we reviewed whole-spine MRI scans of patients who visited the pain clinic complaining of leg and/or low back pain between 2010 and 2019. We analyzed the overall prevalence and prevalence according to the age group, sex, grade of lumbar disc degeneration, and thoracic level. In addition, we identified factors independently associated with stenotic thoracic ligamentum flavum hypertrophy occurrence. RESULTS: Among 1896 patients, the overall prevalence of stenotic thoracic ligamentum flavum hypertrophy was 9.8% (185/1896), with the highest prevalence observed in the ≥80-year-old age group among all age groups (15.9%, 14/88). The region with the highest prevalence was the T10/11 level (3.0%, 57/1896). Multivariable logistic regression analysis revealed that when compared with the <50-year-old age group, all other age groups were significantly associated with stenotic thoracic ligamentum flavum hypertrophy (p<0.01). In addition, grade 5 of lumbar disc degeneration was significantly associated with stenotic thoracic ligamentum flavum hypertrophy (p=0.03). CONCLUSIONS: Given the possibility for missed stenotic thoracic ligamentum flavum hypertrophy to potentially result in neurological complications, extending lumbar spine MRI covering the lower thoracic region may be considered for patients over 50 years of age with suspected severe lumbar disc degeneration.

Reconsidering injection volume for caudal epidural block in young pediatric patients: a dynamic flow tracking experimental study.

INTRODUCTION: Caudal epidural block is a commonly used analgesic technique in pediatric patients. Ultrasound could be used to increase the accuracy of the block by visual confirmation of the drug-spreading. Therefore, we aimed to estimate the cephalad spread of injection volume by caudal route using dynamic ultrasound imaging in young pediatric patients. METHODS: Forty patients, aged 6-24 months, undergoing foot surgery were included. After inducing general anesthesia, an angiocatheter was inserted into the sacral canal under ultrasound guidance. Thereafter, the probe was placed in the paramedian sagittal oblique position, and prepared 0.15% ropivacaine was injected, 1 mL at a time, up to 1.0 mL.kg-1. The ultrasound probe was moved cranially following the bulk flow of local anesthetics. Our primary outcome was the required volume of local anesthetics to reach each level of interlaminar space. RESULTS: The dynamic flow tracking was available in 39 patients, and the required volume of the injectate to reach L5-S1, L4-L5, L3-L4, L2-L3, L1-L2, T12-L1, and T11-T12 was 0.125, 0.223, 0.381, 0.591, 0.797, 0.960, and 1.050 mL.kg-1, respectively. The required volume to reach the immediate upper spinal level was inconsistent across various spinal levels. CONCLUSIONS: Local anesthetics of 0.223, 0.591, and 0.797 mL.kg-1 could provide sufficient analgesia for localized foot, knee, and hip surgeries, respectively. However, since the required volume of the local anesthetics could not be calculated linearly, the real-time dynamic flow tracking technique for the caudal epidural block is recommended in young pediatric patients. TRIAL REGISTRATIONS: ClinicalTrials.gov (NCT04039295).

Outcomes of surgery for coarctation of the aorta based on a new classification system.

OBJECTIVES: To evaluate early- and long-term outcomes of the surgical treatment for coarctation of the aorta based on a new classification system. METHODS: A retrospective clinical review of 111 patients with coarctation of the aorta who underwent surgery (March 2011 to August 2020) was performed. We categorised coarctation of the aorta into type I, with all three head vessels tightly packed; type II, with the left subclavian artery separated from the two other head vessels; and type III, with all three head vessels separated from one another. Each type included subtype a, with a short isthmic portion, and subtype b, with a long isthmic portion. RESULTS: The median patient age and weight at operation were 8 (range, 1-1490) days and 3.2 (range, 1.9-18.5) kg, respectively. Extended end-to-end anastomosis was performed via sternotomy in 54, via thoracotomy in 12, end-to-side anastomosis in 31, autologous main pulmonary artery patch augmentation in 12, and modified end-to-end anastomosis combined with subclavian artery flap aortoplasty in two patients. There was one (0.9%) case of early mortality and 12 (10.8%) cases of post-operative complications. Two (1.8%) late deaths occurred during follow-up. Five (4.5%) patients underwent balloon dilatation and three (2.7%) underwent reoperation for restenosis of coarctation of the aorta. All patients with type Ia (21 patients, 18.9%) underwent extended end-to-end anastomosis via sternotomy or thoracotomy. CONCLUSIONS: According to the early and late outcomes observed in this study, surgical treatment of coarctation of the aorta using the new classification system could be safe and low risk.