Fracture gap and working length are important actionable factors affecting bone union after minimally invasive plate osteosynthesis for the treatment of simple diaphyseal or distal metaphyseal tibia fractures.

INTRODUCTION: Indirect reduction of minimally invasive plate osteosynthesis (MIPO) can often result in delayed union in tibia fractures. This study evaluated several factors in MIPO in relation to bone union. HYPOTHESIS: We hypothesized that the fracture gap, plate - tibia distance, or working length would have a substantial effect on the tibia union rate. MATERIALS AND METHODS: Forty-one patients with simple diaphyseal or distal metaphyseal tibia fractures who underwent internal fixation surgery using the MIPO technique were divided into two groups: patients with delayed union and patients without delayed union. Non-actionable factors involving AO/OTA classification, fibula fracture and actionable factors including postoperative fracture gap, plate - tibia distance, working length in relation to parameters of bone union were compared between the two groups. Also cumulative rates of bone union and risk factors of delayed union according to variables of interest were investigated. RESULTS: AO/OTA classification, site of fibula fracture, postoperative fracture gap, working length, and bone union rate of the two groups significantly differed (p<0.05). The cumulative rate of bone union during 1-year follow-up according to 43A tibia fracture, distal fibula fracture, fracture gap, and working length significantly differed between the two groups (p<0.05). By univariate Cox proportional hazards model, 43A tibia fracture, distal fibula fracture, facture gap, and short working length were risk factors for delayed union (p<0.05). DISCUSSION: Non-actionable factors involving AO/OTA classification, distal fibula fracture and actionable factors including postoperative fracture gap, working length were significant factors affecting bone union after MIPO. The present study indicated that small fracture gap and long working length during MIPO might facilitate bone healing in tibia fracture. LEVEL OF EVIDENCE: IV; single-center retrospective cohort study.

Generation of hepatitis C virus-resistant liver cells by genome editing-mediated stable expression of RNA aptamer.

Hepatitis C virus (HCV) infections frequently recur after liver transplantation in patients with HCV-related liver diseases. Approximately 30% of these patients progress to cirrhosis within 5 years after surgery. In this study, we proposed an effective therapeutic strategy to overcome the recurrence of HCV. CRISPR-Cas9 was used to insert an expression cassette encoding an RNA aptamer targeting HCV NS5B replicase as an anti-HCV agent into adeno-associated virus integration site 1 (AAVS1), known as a "safe harbor," in a hepatocellular carcinoma cell line to confer resistance to HCV. The RNA aptamer expression system based on a dihydrofolate reductase minigene was precisely knocked in into AAVS1, leading to the stable expression of aptamer RNA in the developed cell line. HCV replication was effectively inhibited at both the RNA and protein levels in cells transfected with HCV RNA or infected with HCV. RNA immunoprecipitation and competition experiments strongly suggested that this HCV inhibition was due to the RNA aptamer-mediated sequestration of HCV NS5B. No off-target insertion of the RNA aptamer expression construct was observed. The findings suggest that HCV-resistant liver cells produced by genome editing technology could be used as a new alternative in the development of a treatment for HCV-induced liver diseases.

Thermodynamic Studies on the Hydrolysis of Trivalent Plutonium and Solubility of Pu(OH)3(am).

The temperature-dependent reaction properties of actinide elements are of particular interest in the safety assessment of high-level radioactive waste (HLRW) disposal systems. In this study, the hydrolysis of Pu(III) and the solubility of Pu(OH)3(am) were investigated at various temperatures (10-40 °C) in 0.1 M NaClO4. A strong reducing condition for maintaining the oxidation state of Pu(III) while slowly increasing the pH of the solution was realized by electrolysis. The formation constants of the first hydrolysis species, log *ß1', and the solubility products of Pu(OH)3(am), log *Ks,0', at 10, 17, and 40 °C were experimentally determined using spectrophotometry, laser-induced breakdown detection, and radiometry. The enthalpy and entropy changes for these reactions were estimated using the van't Hoff equation. The first hydrolysis of Pu(III) is endothermic (ΔrHm° = 34.10 ± 4.48 kJ mol-1), and the dissolution of Pu(OH)3(am) is exothermic (ΔrHm° = -294.29 ± 23.05 kJ mol-1) with negative entropy changes. These thermodynamic data will contribute to improving the reliability of the safety assessment of HLRW disposal facilities and understanding the geochemical behavior of Pu under reducing or anoxic aqueous conditions at elevated temperatures.

Computed Tomography-Based Morphologic Analysis of Osteoarthritis of the Distal Radioulnar Joint Associated with Extensor Tendon Ruptures.

BACKGROUD: Although the scallop sign is considered the most important risk factor for extensor tendon ruptures (ETRs) in patients with osteoarthritis of the distal radioulnar joint (DRUJ), previous reports provide a limited understanding of the changes at DRUJ, as risk factors were examined in plain radiographs of the wrist. The aim of this study was to assess the changes of DRUJ using axial images of computed tomography (CT) in patients with DRUJ osteoarthritis and associated ETRs and to evaluate the relationship between the changes of DRUJ and ETRs. METHODS: Twelve patients with ETRs due to osteoarthritis of the DRUJ were enrolled. The changes of DRUJ were examined on axial images of CT and the following 8 parameters were measured: width of radius, anteroposterior (AP) length of radius, width of sigmoid notch (SN), AP length of SN, AP length of ulnar head, subluxation length of ulnar head, dorsal inclination of SN, and distance from Lister's tubercle to SN. Radiological parameters of the DRUJ were measured in 60 control wrists without trauma or osteoarthritis, and the patient and control groups were statistically compared. RESULTS: Statistically significant differences were observed between the patient and control groups in all the radiological parameters except for the AP length of SN and AP length of ulnar head. The width of radius, AP length of radius, width of SN, subluxation length of ulnar head, and dorsal inclination of SN were greater and the distance from Lister's tubercle to SN was smaller in the patient group than in the control group. The width of SN, dorsal inclination of SN, and distance from Lister's tubercle to SN were statistically significant risk factors among the 8 parameters. CONCLUSIONS: ETRs due to osteoarthritis of the DRUJ was related to the changes of DRUJ, especially the changes around SN of the distal radius. In addition to the existing risk factors, a decreased distance from Lister's tubercle to SN and increased dorsal inclination of SN were identified as new risk factors. Axial images of CT were effective to evaluate degenerative changes at the DRUJ.

Evaluation of the uninjured anterior talofibular ligament by ultrasound for assessing generalized joint hypermobility.

BACKGROUND: Most clinicians use the Beighton score to assess generalized joint hypermobility (GJH) when deciding on the treatment of chronic lateral ankle instability (CLAI). The purpose of the study was to evaluate anterior talofibular ligament (ATFL) status by ultrasound and correlate these values with Beighton scores and the manual anterior drawer test (ADT). METHODS: The participants were divided into two groups, those without GJH (24 ankles) and with GJH (20 ankles). For the investigation of ATFL, resting and stress ultrasonography was performed to assess the length, height (degree of loosening) and thickness. Beighton scores, manual ADT grades and ultrasound parameters of participants with and without GJH were compared. The correlation coefficients among those values were analyzed. RESULTS: The mean ATFL length, resting height, stress height and mean difference in height between resting and stress ATFL were all significantly different between the two groups (P < .05). The resting and stress ATFL length, height, and difference in height between resting and stress ATFL showed a positive linear relationship with Beighton scores and manual ADT grades (P < .05). CONCLUSIONS: The ATFL stress ultrasound parameters showed significant differences between participants with high and low Beighton scores and were correlated with Beighton scores and manual ADT grades. LEVEL OF EVIDENCE: Cross-sectional cohort study; Level of evidence IV.

Mutation spectrum and biochemical features in infants with neonatal Dubin-Johnson syndrome.

BACKGROUND: Dubin-Johnson syndrome (DJS) is an autosomal recessive disorder presenting as isolated direct hyperbilirubinemia.DJS is rarely diagnosed in the neonatal period. The purpose of this study was to clarify the clinical features of neonatal DJS and to analyze the genetic mutation of adenosine triphosphate-binding cassette subfamily C member 2 (ABCC2). METHODS: From 2013 to 2018, 135 infants with neonatal cholestasis at Seoul National University Hospital were enrolled. Genetic analysis was performed by neonatal cholestasis gene panel. To clarify the characteristics of neonatal DJS, the clinical and laboratory results of 6 DJS infants and 129 infants with neonatal cholestasis from other causes were compared. RESULTS: A total of 8 different ABCC2 variants were identified among the 12 alleles of DJS. The most common variant was p.Arg768Trp (33.4%), followed by p.Arg100Ter (16.8%). Three novel variants were identified (p.Gly693Glu, p.Thr394Arg, and p.Asn718Ser). Aspartate transaminase (AST) and alanine transaminase (ALT) levels were significantly lower in infants with DJS than in infants with neonatal cholestasis from other causes. Direct bilirubin and total bilirubin were significantly higher in the infants with DJS. CONCLUSIONS: We found three novel variants in 6 Korean infants with DJS. When AST and ALT levels are normal in infants with neonatal cholestasis, genetic analysis of ABCC2 permits an accurate diagnosis.

Bilateral congenital absence of the anterior cruciate ligament associated with bilateral knee and hip osteoarthritis: Case report.

INTRODUCTION: Congenital absence of the cruciate ligaments is very rare condition. Its association with congenital abnormalities of the spine, knee and hip, has been rarely reported. Most of the case reports were mostly reported before adolescence, so reports of the progression of this congenital disease at old age were extremely rare. PRESENTATION OF CASE: A 65-year-old woman had a 7-year history of both knee and hip pain. On physical examination, valgus and varus instability on both knees and painful limitation of motion in both hip joints were observed. Radiography and magnetic resonance imaging showed the absence of the anterior cruciate ligament with osteoarthritis on both knees and hip osteoarthritis. Total knee and hip arthroplasties were performed on both knee joints and total hip arthroplasty. The pain and instability of both knees and hips were lost for follow up of more than a year, and the patient is doing well in daily life. DISCUSSION: Congenital absence of cruciate ligament may progress to osteoarthritis, do early detection and proper management is needed. In the treatment of older aged patients. Reports of treatment for this disorder are also very rare in older age. In old age, arthroplasty can be a useful treatment when the severe osteoarthritis is accompanied by instability. CONCLUSION: Since the congenital absence of the ACL in old age could lead to hip and knee osteoarthritis, periodic follow-up is necessary and arthroplasty can be a useful treatment when the severe osteoarthritis is accompanied by instability.

Molecular diagnosis of glycogen storage disease type IX using a glycogen storage disease gene panel.

Glycogen storage disease type IX (GSD IX) is caused by a deficiency of hepatic phosphorylase kinase. The aim of this study was to clarify the clinical features, long term outcomes, and genetic analysis of GSD IX in Korea. A GSD gene panel was created and hybridization capture-based next-generation sequencing was performed. We investigated clinical laboratory data, results of molecular genetic analysis, liver biopsy findings, and long-term outcomes. Ten children were diagnosed with GSD IX at Seoul National University Children's Hospital. Hypoglycemia, hyperlactacidemia, hypertriglyceridemia, hyperuricemia, liver fibrosis on liver biopsy, and short stature was found in 30%, 56%, 100%, 60%, 80% and 50% of the children, respectively. Seven PHKA2 variants were identified in eight children with GSD IXa-one nonsense (c.2268dupT; p.(Asp757Ter)), two splicing (c.918+1G > A, c.718-2A > G), one frameshift (c.405_419delinsTCCTGGCC; p.(Asp136ProfsTer11)), and three missense variants (c.3628G > A; p.(Gly1210Arg), c.1245G > T and c.2746C > T; p.(Arg916Trp)). Two variants of PHKG2 were identified in two children with GSD IXc-one frameshift (c.783delC; p.(Ser262AlafsTer6)) and one missense (c.661G > A; p.(Val221Met)). Elevated liver enzymes and hypertriglyceridemia in children with GSD IXa tended to improve with age. For the first time, we report hepatocellular carcinoma in a patient with GSD IXc. The GSD gene panel is a useful diagnostic tool to confirm GSD IX. The clinical phenotype of GSD IXc is severe and monitoring for the development of hepatocellular carcinoma should be implemented.

Dynamic Analysis of Sphere-Like Iron Particles Based Magnetorheological Damper for Waveform-Generating Test System.

In this study, a new double pulse waveform-generating test system with an integrated magnetorheological (MR) damper is proposed. Since the total shear stress of MR fluid can be varied according to the shape of particles, sphere-like iron particles-based MR fluid is filled into the MR damper. The test system consists of a velocity generator, three masses (impact, test, and dummy), a spring, and an MR damper. To tune the double pulse waveform profile, a damping force model is constructed to determine the fundamental parameters of the simulator. Then, the first and second shock waveform profiles are analyzed to solve the governing equation of motions representing the damping force and velocity. The mathematical model of the MR damper is formulated and applied to a simulator with a graphical user interface programmed using MATLAB. The effectiveness of the proposed simulator-featuring controllable MR damper is demonstrated by comparing the simulation and experimental results.

Fully automated platelet isolation on a centrifugal microfluidic device for molecular diagnostics.

Platelets play crucial roles in hemostasis and immunity. Over the last decades, clinical evidence has revealed the significance of platelets as complementary biomarkers for the detection and treatment of various diseases, including cancer. Due to a lack of well standardized convenient isolation methods for platelets, pre-analytical factors such as complex handling procedures negatively impact the quality of the platelet samples, including overactivation, low purity, and poor reproducibility. This may lead to biased interpretation of various downstream analyses, such as proteomic and genomic analyses. Herein, we describe a fully automated lab-on-a-disc-based method of platelet isolation from a small volume of blood (<1 mL). This method provides higher yields (>4 folds) and purity (>99%) and lower platelet activation than the conventional method. Moreover, it was also superior in the detection of platelet-related RNAs CD41, PF4, and P2Y12 due to lower contamination with white blood cells.

Fully automated, on-site isolation of cfDNA from whole blood for cancer therapy monitoring.

The potential utility of circulating tumour DNA (ctDNA) in patient blood for cancer diagnostics and real-time monitoring of disease progression is highly recognized. However, the lack of automated and efficient methods for cell-free DNA (cfDNA) isolation from peripheral blood has remained a challenge for broader acceptance of liquid biopsy in general clinical settings. Here, we demonstrate a lab-on-a-disc system equipped with newly developed, electromagnetically actuated, and reversible diaphragm valves that allows fully automated and rapid (<30 min) isolation of cfDNA from whole blood (>3 ml) to achieve high detection sensitivity by minimizing the degradation of fragile ctDNA as well as contamination of wild-type DNA from abundant blood cells. As a proof of concept study, we used the lab-on-a-disc to isolate cfDNA from patients with non-small cell lung cancer and successfully detected epidermal growth factor receptor gene mutations (L858R, T790M) during targeted drug therapy. The proposed lab-on-a-disc enables a fully automated, rapid, and point-of-care cfDNA enrichment starting from whole blood to facilitate the wide use of liquid biopsy in routine clinical practice.

Two-Photon Probes for pH: Detection of Human Colon Cancer using Two-Photon Microscopy.

We have developed two-photon (TP) pH-sensitive probes (BH-2 and BHEt-1) that exhibit absorption and emission maxima at 370 and 466 nm, and TP absorption cross-section values of 51 and 61 GM (1 GM = 10-50cm4s/photon), respectively, at 750 nm and pH 3.0 in a universal buffer (0.1 M citric acid, 0.1 M KH2PO4, 0.1 M Na2B4O7, 0.1 M Tris, 0.1 M KCl)/1,4-dioxane (7/3) solution. The TPM images of CCD-18co (a normal colon cell line) and HCT116 cells (a colon cancer cell line) labeled with BH-2 were too dim to be distinguished. When the same cells were labeled with BHEt-1, however, the TPM image of the HCT116 cells was much brighter than that of CCD-18co cells, and the relative proportion of the acidic vesicles (Pacid) of the former was 5-fold larger than that of latter. BHEt-1 could also differentiate HepG2 cells (a human liver cancer cell line) from LX-2 cells (a human hepatic stellate cell line) with a 6-fold larger Pacid value. Human colon cancer tissues labeled with BHEt-1 showed similar results, demonstrating much brighter TPM images and 6-fold larger Pacid values compared to normal tissue. These results suggest the potential utility of BHEt-1 for detecting colon cancer in human tissues using TPM.

Circulating tumor cells detected by lab-on-a-disc: Role in early diagnosis of gastric cancer.

BACKGROUND: The use of circulating tumor cells (CTCs) as an early diagnostic biomarker and prognostic indicator after surgery or chemotherapy has been suggested for various cancers. This study aimed to evaluate CTCs in patients who underwent gastrectomy for gastric cancer and to explore their clinical usefulness in the early diagnosis of gastric cancer. METHODS: A total of 116 patients with gastric cancer who underwent gastrectomy and 31 healthy volunteers were prospectively included between 2014 and 2015. Peripheral blood samples were collected before gastrectomy, and CTCs were examined using a centrifugal microfluidic system with a new fluid-assisted separation technique. RESULTS: After creating a receiver operating characteristic curve to identify the discriminative CTC value needed differentiate patients with gastric cancer from healthy volunteers, sensitivity and specificity were nearly optimized at a CTC threshold of 2 per 7.5 mL of blood. Of the 102 persons with a CTC level ≥2 per 7.5 mL of blood, 99 (97.1%) had gastric cancer, and of the 45 persons with a CTC level <2 per 7.5 mL of blood, 28 (62.2%) were healthy controls. Accordingly, the sensitivity and specificity for the differentiation of patients with gastric cancer from healthy controls were 85.3% and 90.3%, respectively. However, the presence of CTCs was not associated with any clinicopathologic features such as staging, histologic type, or mucin phenotype. CONCLUSION: Although we could not prove the clinical feasibility of CTCs for gastric cancer staging, our results suggest a potential role of CTCs as an early diagnostic biomarker of gastric cancer.

Exodisc for Rapid, Size-Selective, and Efficient Isolation and Analysis of Nanoscale Extracellular Vesicles from Biological Samples.

Extracellular vesicles (EVs) are cell-derived, nanoscale vesicles that carry nucleic acids and proteins from their cells of origin and show great potential as biomarkers for many diseases, including cancer. Efficient isolation and detection methods are prerequisites for exploiting their use in clinical settings and understanding their physiological functions. Here, we presented a rapid, label-free, and highly sensitive method for EV isolation and quantification using a lab-on-a-disc integrated with two nanofilters (Exodisc). Starting from raw biological samples, such as cell-culture supernatant (CCS) or cancer-patient urine, fully automated enrichment of EVs in the size range of 20-600 nm was achieved within 30 min using a tabletop-sized centrifugal microfluidic system. Quantitative tests using nanoparticle-tracking analysis confirmed that the Exodisc enabled >95% recovery of EVs from CCS. Additionally, analysis of mRNA retrieved from EVs revealed that the Exodisc provided >100-fold higher concentration of mRNA as compared with the gold-standard ultracentrifugation method. Furthermore, on-disc enzyme-linked immunosorbent assay using urinary EVs isolated from bladder cancer patients showed high levels of CD9 and CD81 expression, suggesting that this method may be potentially useful in clinical settings to test urinary EV-based biomarkers for cancer diagnostics.

FAST: Size-Selective, Clog-Free Isolation of Rare Cancer Cells from Whole Blood at a Liquid-Liquid Interface.

Circulating tumor cells (CTCs) have great potential to provide minimally invasive ways for the early detection of cancer metastasis and for the response monitoring of various cancer treatments. Despite the clinical importance and progress of CTC-based cancer diagnostics, most of the current methods of enriching CTCs are difficult to implement in general hospital settings due to complex and time-consuming protocols. Among existing technologies, size-based isolation methods provide antibody-independent, relatively simple, and high throughput protocols. However, the clogging issues and lower than desired recovery rates and purity are the key challenges. In this work, inspired by antifouling membranes with liquid-filled pores in nature, clog-free, highly sensitive (95.9 ± 3.1% recovery rate), selective (>2.5 log depletion of white blood cells), rapid (>3 mL/min), and label-free isolation of viable CTCs from whole blood without prior sample treatment is achieved using a stand-alone lab-on-a-disc system equipped with fluid-assisted separation technology (FAST). Numerical simulation and experiments show that this method provides uniform, clog-free, ultrafast cell enrichment with pressure drops much less than in conventional size-based filtration, at 1 kPa. We demonstrate the clinical utility of the point-of-care detection of CTCs with samples taken from 142 patients suffering from breast, stomach, or lung cancer.

A lab-on-a-disc with reversible and thermally stable diaphragm valves.

A lab-on-a-disc is a unique microfluidic platform that utilizes centrifugal force to pump liquids. This offers many benefits for point-of-care devices because it eliminates the need for connections to multiple pumps and complex tubing connections. A wide range of applications including clinical chemistry, immunoassay, cell analysis, and nucleic acid tests could be demonstrated on a spinning disc. To enable the performance of assays in a fully integrated and automated manner, the robust actuation of integrated valves is a prerequisite. However, conventional passive-type valves incur a critical drawback in that their operation is dependent on the rotational frequency, which is easily influenced by the channel geometry and chemistry, in addition to the physical properties of the liquids to be transferred. Even though a few active-type valving techniques permit the individual actuation of valves, independent of the rotational frequency, complex procedures for the fabrication as well as actuation mechanisms have prevented their broader acceptance in general applications. Here, we report on a lab-on-a-disc incorporating individually addressable diaphragm valves (ID valves) that enable the reversible and thermally stable actuation of multiple valves with unprecedented ease and robustness. These ID valves are configured from an elastic epoxy diaphragm embedded on a 3D printed push-and-twist valve, which can be easily actuated by a simple automatic driver unit. As a proof of concept experiment, an enzyme-linked immunosorbent assay (ELISA) and a polymerase chain reaction (PCR) were performed on a disc in a fully automated manner to demonstrate the robust, reversible, leak-free, and thermally stable actuation of the valves.

Sodium (Na+) concentration effects on metabolic pathway and estimation of ATP use in dark fermentation hydrogen production through stoichiometric analysis.

Batch experiments were conducted to investigate the effects of Na(+) concentration on hydrogen production with dark fermentation. The Na(+) concentration was varied from 0 to 8 g/L in the mixed culture using an anaerobic sludge treated by acid. The maximum hydrogen production was achieved with 1 g-Na(+)/L, whereas the hydrogen production was decreased over 2 g-Na(+)/L due to the inhibitory of Na(+). The mechanisms of Na(+) inhibition to the hydrogen production are studied using pure culture of Clostridium butyricum by calculating the energy balance. At a high sodium concentration, C. butyricum used a greater proportion of the ATP generated via fermentation for cell maintenance rather than for cell synthesis. Additionally, higher Na(+) concentrations shifted the fermentation process toward the acetate synthesis pathway instead of the butyrate pathway, and the value of Y(X/ATP) decreased. With high Na(+) concentrations, a greater ratio of hydrogen was produced via the oxidation of NADH. Excess hydrogen production decreased as the Na(+) concentration increased.

Radiofrequency thermocoagulation of the thoracic splanchnic nerve in functional abdominal pain syndrome -A case report-.

The thoracic splanchnic nerve block has been used in managing abdominal pain, especially for pains arising from abdominal cancers. A 27-year-old male patient who had a constant abdominal pain was referred to our clinic for pain management but had no organic disease. The numeric rating scale (NRS) for pain scored 7/10. We applied a diagnostic thoracic splanchnic nerve block under the diagnosis of functional abdominal pain syndrome. Since the block reduced the pain, we applied a radiofrequency thermocoagulation at the T11 and T12 vertebral level. Thereafter, his symptoms improved markedly with pain decreasing to an NRS score of 2-3/10. Hereby, we report a successful management of functional abdominal pain via radiofrequency thermocoagulation of the thoracic splanchnic nerves.

Novel Use of Hydromorphone as a Pretreatment Agent: A Double-blind, Randomized, Controlled Study in Adult Korean Surgical Patients.

BACKGROUND: Hydromorphone is a potent µ-opioid selective agonist that has an onset time within 5 minutes and reaches peak effect between 10 and 20 minutes. However, it may show immediate analgesic effect to rocuronium-induced pain because of its peripheral analgesic property and also may attenuate noxious stimuli from tracheal intubation during induction. The opioid receptors are known to be present in peripheral sensory nerve terminals as well as in the dorsal root ganglion and the central terminal of primary afferent nerves. Therefore, we hypothesized that hydromorphone may be considered a potent pretreatment or adjuvant drug during the induction of anesthesia with its peripherally and centrally mediated analgesia. OBJECTIVE: The aim of this study was to compare the effects of pretreatment with hydromorphone in reducing rocuronium-induced withdrawal movements and hemodynamic changes during tracheal intubation with the effects of fentanyl and normal saline. METHODS: In this double-blind, randomized, controlled study, consecutive adult patients aged 20 to 70 years who were scheduled to undergo general anesthesia for elective gastric or colorectal surgery at the Samsung Seoul Hospital (Seoul, Republic of Korea) were randomly assigned to receive 5 mL hydromorphone 0.03 mg/kg or fentanyl 2 µg/kg or normal saline. Thirty seconds after administering the study drug, anesthesia was induced with 2.5% thiopental sodium 5 mg/kg. After loss of consciousness, rocuronium 0.6 mg/kg was injected and immediate withdrawal movements were recorded. Two minutes after rocuronium injection, tracheal intubation was performed and hemodynamic changes were observed. RESULTS: A total of 194 patients were enrolled, with 65 in the hydromorphone group, 67 in the fentanyl group, and 62 in the saline group. The overall incidence of withdrawal movements was significantly lower in the hydromorphone group (2 patients; 3.1%) and the fentanyl group (5 patients; 7.5%) (both, P < 0.001) than in the saline group (36 patients; 58.1%). The mean arterial pressure (MAP) and heart rate (HR) after intubation (median [interquartile range]) in the fentanyl group (101.5 [84-115] mm Hg; 93.5 [82-102] beats per minute [bpm]) and the hydromorphone group (93.0 [83-106] mm Hg; 90.0 [86.3-93.6] bpm) were significantly lower than these measures in the saline group (111.5 [105-123] mm Hg; 103.5 [96-113] bpm) (fentanyl group MAP and HR, P < 0.001; hydromorphone group MAP and HR, P < 0.001). CONCLUSIONS: Pretreatment with hydromorphone and fentanyl may have similar effectiveness in reducing withdrawal movements in response to rocuronium injection pain and inducing immediate general anesthesia.

Can gabapentin help reduce postoperative pain in arthroscopic rotator cuff repair? A prospective, randomized, double-blind study.

PURPOSE: The aim of the study was to determine the effect of low-dose gabapentin on postoperative pain management in patients undergoing arthroscopic rotator cuff repair. METHODS: This randomized, double-blinded, placebo-controlled study included 46 patients. The patients were divided into 2 groups according to the drug administered 2 hours before surgery, either 300 mg of gabapentin or placebo. The primary outcome measure was the visual analog scale (VAS) score at 2, 6, 12, and 24 hours postoperatively. The secondary outcome measures were fentanyl consumption and side effects during the first 2 hours in the postanesthesia care unit and then at 6 and 24 hours postoperatively. The patients were evaluated for side effects including nausea, vomiting, respiratory depression, dizziness, drowsiness, voiding difficulty, and pruritus. RESULTS: The VAS scores at 2, 6, and 12 hours postoperatively were significantly lower in the gabapentin group than in the placebo group (P = .023, P = .019, and P = .022, respectively). The consumption of fentanyl, over a period of 24 hours, was not different in the comparisons between the groups (P = .686). The incidence of side effects was similar in the 2 groups. CONCLUSIONS: A single dose of 300 mg of gabapentin reduced the VAS score during the first 24 hours postoperatively in patients undergoing shoulder arthroscopic rotator cuff repair, without significant side effects when compared with placebo. However, the fentanyl consumption did not differ between the gabapentin and placebo groups. LEVEL OF EVIDENCE: Level I, randomized controlled trial.