PURPOSE: We wanted to analyze the causes of revision and the clinical and radiographic results after revision total knee arthroplasty. MATERIALS AND METHODS: Thirty-eight knees in 34 patients underwent revision total knee arthroplasty using the PFC(R) Sigma revision system between March 1999 and May 2005. The average patient age was 71.2 years, and the average follow-up period was 6 years 7 months (range: 4 years~10 years 2 months). We evaluated the time interval between the primary and revision arthroplasty and the causes of revision. The clinical outcomes were assessed using the knee score and the functional score of the Knee Society Scoring system (KSS system), and the radiographic measurements were assessed using the roentgenographic method of the American Knee Society. RESULTS: The mean interval between primary and revision arthroplasty was 6 years 3 months. The causes of revision included 25 cases of aseptic loosening and osteolysis, 7 cases of infection, 3 cases of joint stiffness and 3 cases of polyethylene problems. At the follow up, the mean preoperative knee and functional scores improved from 45.1 points to 84.5 and 37.2 to 78.2, respectively. Radiographycally, the average femorotibial angle was corrected from 2.2degrees in valgus to 6.5degrees. The radiolucency score was below 4 in all the cases. The complications after revision arthroplasty were 2 cases of superficial infection and 1 case of wound dehiscence with a skin defect. CONCLUSION: The main causes of revision arthroplasty were aseptic loosening and osteolysis. Satisfactory results were obtained using the posterior cruciate ligament and substituting the PFC(R) Sigma knee system with appropriately selected metal augmentation and an allograft. This study showed favorable results on long term follow-up.
Arthroplasty ; Follow-Up Studies ; Humans ; Joints ; Knee ; Osteolysis ; Polyethylene ; Posterior Cruciate Ligament ; Skin ; Transplantation, Homologous

No abstract available.
Morphine* ; Respiration, Artificial* ; Weaning*

BACKGROUND: A randomized, multicenter, open-label, parallel group study was performed to compare the effects of remifentanil and morphine as analgesic drugs on the duration of weaning time from mechanical ventilation (MV). METHODS: A total of 96 patients with MV in 6 medical and surgical intensive care units were randomly assigned to either, remifentanil (0.1-0.2 mcg/kg/min, n = 49) or morphine (0.8-35 mg/hr, n = 47) from the weaning start. The weaning time was defined as the total ventilation time minus the sum of controlled mode duration. RESULTS: Compared with the morphine group, the remifentanil-based analgesic group showed a tendency of shorter weaning time (mean 143.9 hr, 89.7 hr, respectively: p = 0.069). Secondary outcomes such as total ventilation time, successful weaning rate at the 7th of MV day was similar in both groups. There was also no difference in the mortality rate at the 7th and 28th hospital day. Kaplan-Meyer curve for weaning was not different between the two groups. CONCLUSIONS: Remifentanil usage during the weaning phase tended to decrease weaning time compared with morphine usage.
Analgesics ; Humans ; Critical Care ; Morphine* ; Mortality ; Respiration, Artificial* ; Ventilation ; Ventilator Weaning ; Weaning*

PURPOSE: The purpose of this study was to propose and test a predictive model that could explain and predict nursing productivity. METHODS: A survey using a structured questionnaire was conducted with 360 nurses in Korea. The data were analyzed using SPSS Windows 18.0 and AMOS 19.0 program. RESULTS: Based on the constructed model, burnout and organizational commitment were found to have direct effects on nurses' turnover intention and nursing productivity. While nursing work environment was found to have indirect effects on nurses' turnover intention and nursing productivity. CONCLUSION: This structural equational model is a comprehensive theoretical model that explains the related factors and their relationship with nursing productivity. Comprehensive organizational interventions to improve nursing productivity should focus on improving the nursing work environment. Findings from this study can be used to design appropriate strategies to decrease nurse turnover in Korea. Further studies are needed to prospectively verify these causal relationships with larger samples.
Adult ; Attitude of Health Personnel ; Burnout, Professional/psychology ; Female ; Humans ; Job Satisfaction ; *Models, Theoretical ; Nursing Staff, Hospital/*psychology ; Organizational Culture ; Personnel Turnover ; Questionnaires ; Republic of Korea

BACKGROUND: Radiofrequency (RF) lesioning is one of the most frequently used neurolytic techniques for the relief of pain. Technical advances enables one to make a more reliable and reproducible lesion production. If the size at different parameters is known, the maximal effects and reduction of the side effects could be achieved. However, its size can not be measured systematically using thermocouple (TC) electrodes. 'Differential selection of pain fibers' was proposed but there was not any neuropathologic evidence. We studied pathologic changes produced with various sizes and shapes of electrodes using different parameters. METHODS: Using fresh egg white, RF lesions were produced by four different electrodes at 65, 70, 75, 80 and 90degreesC. At each temperature, Photographs were taken at 10, 20, 30, 40, 50, 60, 90 and 120 seconds. Using the sciatic nerve of the rats, we performed RF lesioning utilizing two different electrodes at 70, 80 and 90degreesC and dissected them 1, 7, and 30 days after treatment. The pathologic changes of lesions were studied and analyzed by applying a quantitative experimental scoring system on the light and electron microscopy (LM and EM). RESULTS: The lesion size increased with a higher temperature and larger electrode. Among the electrodes with the same thickness, the lesion size with the longer electrode was larger than the shorter one. In a histopathologic study, there were significant changes with time, but no significant changes with different electrode and temperature. On electron microscope (EM), large myelinated fibers were relatively intact on RF lesion of 80degreesC after 1 day. 7 days after treatment, there were significant inflammatory cell infiltration and axonal regeneration. At 30 days after the same treatment, there were relatively large amount of small myelinated fibers and unmyelinated fibers. CONCLUSIONS: We measured the lesions systematically with different parameters expecting the result can be used as the reference for the RF lesion. There were no histopathologic differences on LM at different electrodes and temperatures. But we found the evidence of 'differential selection of pain fibers' with 22 gauge electrode at 80degreesC. And also we found the axonal regeneration as early as 1 week later. We learned the neuropathic pain can be induced by pathologic changes, such as bleb formation, inflammatory cell infiltration and predominance of small myelinated and unmyelinated fibers.
Animals ; Axons ; Blister ; Egg White ; Electrodes ; Microscopy, Electron ; Myelin Sheath ; Neuralgia ; Peripheral Nerves* ; Rats ; Regeneration ; Sciatic Nerve

BACKGROUND: A randomized, multicenter, open-label, parallel group study was performed to compare the effects of remifentanil and morphine as analgesic drugs on the duration of weaning time from mechanical ventilation (MV). METHODS: A total of 96 patients with MV in 6 medical and surgical intensive care units were randomly assigned to either, remifentanil (0.1-0.2 mcg/kg/min, n = 49) or morphine (0.8-35 mg/hr, n = 47) from the weaning start. The weaning time was defined as the total ventilation time minus the sum of controlled mode duration. RESULTS: Compared with the morphine group, the remifentanil-based analgesic group showed a tendency of shorter weaning time (mean 143.9 hr, 89.7 hr, respectively: p = 0.069). Secondary outcomes such as total ventilation time, successful weaning rate at the 7th of MV day was similar in both groups. There was also no difference in the mortality rate at the 7th and 28th hospital day. Kaplan-Meyer curve for weaning was not different between the two groups. CONCLUSIONS: Remifentanil usage during the weaning phase tended to decrease weaning time compared with morphine usage.
Analgesics ; Humans ; Critical Care ; Morphine ; Mortality ; Respiration, Artificial ; Ventilation ; Ventilator Weaning ; Weaning

No abstract available.
Morphine ; Respiration, Artificial ; Weaning

We report a case of acute hemolytic transfusion reaction due to multiple alloantibodies. A 41-year-old male with multiple histories of transfusion was admitted for jaundice and oliguria after receiving two units of red blood cells in a local clinic. He showed acute renal failure and disseminated intravascular coagulation. Direct Coombs test was negative and antibody screening test showed strong positive results. Anti-E, anti-c, and anti-Jk(b) antibodies were identified in two panels of unexpected antibody assays. Acute hemolytic transfusion was diagnosed, and he was discharged after 1 month of supportive treatment. Unexpected antibody detection tests, including the antiglobulin phase, should be performed to prevent adverse transfusion reactions by unexpected antibodies. Better precision and quality control are necessary when performing pre-transfusion tests.
Acute Kidney Injury ; Adult ; Antibodies ; Coombs Test ; Disseminated Intravascular Coagulation ; Erythrocytes ; Humans ; Isoantibodies* ; Jaundice ; Male ; Mass Screening ; Oliguria ; Quality Control ; Transfusion Reaction*

BACKGROUND: Understanding the electrophysiology of radiofrequency (RF) lesions and determining the size and shape of RF lesions is important for reducing side effects when applied to patients in a clinical setting. We compared the shape and size of RF thermocoagulation produced by straight and curved 20-gauge electrodes and considered its application in clinical settings. METHODS: The white from a fresh hen's egg was warmed to 37oC and placed in a rectangular glass container. Straight and curved 20-gauge electrodes were immersed. The transparency of the egg white and the glass container made it possible to photograph the changes in size of the RF lesions over time. We applied thermocoagulation for 60 seconds at 70, 80, and 90oC. Photographs were taken at 60 seconds. We measured the maximal size of the lesions. A two-way statistical analysis of variance was performed. RESULTS: The thermocoagulations were started at the junction of the insulated and uninsulated portion of the electrode and did not extended beyond the tip. The thermocoagulation size was 4.2 +/- 0.8 at 70oC, 6.1 +/- 2.9 at 80oC and 6.1 +/- 1.9 at 90oC using the 20-gauge, 10 mm active tip, straight electrode and 4.5 +/- 1.1 at 70oC, 7.2 +/- 1.9 at 80oC and 7.9 +/- 2.7 at 90oC using the 20-gauge, 10 mm active tip, curved electrode. There was no observable difference in the size of the lesions produced by the straight and curved electrodes. CONCLUSIONS: We found that temperature was the more important factor in determining lesion size. When the temperature setting is the same, lesions produced by straight and curved electrode of the same gauge are also same size. Therefore the choice of straight or curved electrode should be made to optimize ease of handling and ensure proper location of the electrode tip.
Egg White ; Electrocoagulation ; Electrodes* ; Electrophysiology ; Glass ; Humans ; Ovum

BACKGROUND: To prevent unsolved problems of medical devices, we hypothesized that combinatorial effects of zwitterionic functional group and anti-bacterial metal ions can reduce effectively the thrombosis and bacterial infection of polymeric biomaterials. In this research, we designed a novel series of zwitterionic polyurethane (zPU) additives to impart anti-thrombotic properties to a polyvinyl chloride (PVC) matrix. METHODS: We have synthesized zPUs by combination of various components and zPUs complexed with metal ions. Zwitterion group was prepared by reaction with 1,3-propane sultone and Nmethyldiethanolamine and metal ions were incorporated into sulfobetaine chains via molecular complexation. These zPU additives were characterized using FT-IR, 1H-NMR, elemental analysis, and thermal analysis. The PVC film blended with zPU additives were prepared by utilizing a solvent casting and hot melting process. RESULTS: Water contact angle demonstrated that the introduction of zwitterion group has improved hydrophilicity of polyurethanes dramatically. Protein adsorption test resulted in improved anti-fouling effects dependent on additive concentration and decreases in their effects by metal complexation. Platelet adhesion test revealed anti-fouling effects by additive blending but not significant as compared to protein resistance results. CONCLUSION With further studies, the synthesized zPUs and zPUs complexed with metal ions are expected to be used as good biomaterials in biomedical fields. Based on our results, we can carefully estimate that the enhanced anti-fouling effect contributed to reduced platelet adhesion.