Kazuhiko Ohe

Electromagnetic interference on medical equipment by low-power mobile telecommunication systems

There have been a number of reports of electromagnetic interference (EMI) on electronic medical equipment caused by mobile telecommunication systems. In Japan, the use of the personal handy-phone system (PHS) has greatly expanded within urban areas, PHS handsets transmit EM signals at a frequency of 1.9 GHz and have a peak radiated power of 80 mW. This power level is lower than that of other mobile telecommunication systems. Two studies were carried out. One was to determine whether or not PHS interferes with electronic medical equipment in hospitals. We observed no EMI on electronic medical equipment when the PHS handset was in either the speaking mode or on standby. The second study was to observe EMI from 1.9-GHz signals at several radiation power levels. Although EMI was not observed at the radiated peak power of the PHS handset, EMI on some of the tested equipment was observed when the radiated power was ten or more times higher than that of the PHS handset.

Analysis of factors affecting operating time, postoperative complications, and length of stay for total knee arthroplasty: nationwide web-based survey

BackgroundThis study aimed to clarify the impact of various factors on the operating time, postoperative complications, and length of stay (LOS) after total knee arthroplasty (TKA).MethodsWe identified 3577 TKAs performed in 345 hospitals in Japan from November 2006 to March 2007. We examined the patient characteristics, surgical procedure details, hospital and surgeon volumes, and outcome variables (operating time, postoperative complications, LOS).ResultsThe average operating time was 127 ± 47 min. The rate of postoperative complications was 9.8%. The average LOS was 35.1 ± 15.9 days. In multivariate regression analyses, the average operating times were significantly shorter at hospitals with >10 cases per year compared to hospitals with <10 cases per year and for surgeons with ≥100 total cases compared to surgeons with <100 total cases. A longer operating time was associated with revision surgery and use of computer navigation. Significant predictors of postoperative complications were age, body mass index, and cerebrovascular disease. Shorter LOS was associated with higher hospital volume and use of a clinical pathway, whereas age, cardiovascular disease, and revision surgery increased the length of stay.ConclusionsPostoperative complications following TKA mainly depended on patient-based factors and were not significantly affected by the surgeon’s experience.

Risk factors affecting inhospital mortality after hip fracture: retrospective analysis using the Japanese Diagnosis Procedure Combination Database

Objective To identify risk factors for inhospital mortality in patients with hip fractures using the Japanese Diagnosis Procedure Combination (DPC) nationwide administrative claims database. Design Retrospective observational study. Setting Hospitals adopting the DPC system during 2007–2009. Participants The authors analysed a total of 80 800 eligible patients aged ≥60 years with a single hip fracture (International Classification of Diseases, 10th Revision codes: S72.0 and S72.1). The DPC database includes patients treated between July and December each year. Main outcome measures Inhospital mortality after hip fracture. Results The overall inhospital mortality rate after hip fractures was 3.3%. Multivariate analysis indicated that inhospital mortality was significantly associated with male gender (OR 2.12, 95% CI 1.94 to 2.31), advancing age and number of comorbidities. Significantly higher mortality was observed in those treated conservatively (OR 4.25, 95% CI 3.92 to 4.61). Surgical delays of 5 days or more were significantly associated with higher rates of inhospital mortality (OR 1.34, 95% CI 1.20 to 1.50). Conclusions In patients with hip fractures, male gender, advancing age, high number of comorbidities, conservative treatment and the surgical delay of 5 days or more were associated with higher rates of inhospital mortality.

Mortality and morbidity after high-dose methylprednisolone treatment in patients with acute cervical spinal cord injury: a propensity-matched analysis using a nationwide administrative database

Objective To examine the magnitude of the adverse impact of high-dose methylprednisolone treatment in patients with acute cervical spinal cord injury (SCI). Methods We examined the abstracted data from the Japanese Diagnosis Procedure Combination database, and included patients with ICD-10 code S141 who were admitted on an emergency basis between 1 July and 31 December in 2007–2009. The investigation evaluated the patients’ sex, age, comorbidities, Japan Coma Scale, hospital volume and the amount of methylprednisolone administered. One-to-one propensity-score matching between high-dose methylprednisolone group (>5000 mg) and control group was performed to compare the rates of in-hospital death and major complications (sepsis; pneumonia; urinary tract infection; gastrointestinal ulcer/bleeding; and pulmonary embolism). Results We identified 3508 cervical SCI patients (2652 men and 856 women; mean age, 60.8±18.7 years) including 824 (23.5%) patients who received high-dose methylprednisolone. A propensity-matched analysis with 824 pairs of patients showed a significant increase in the occurrence of gastrointestinal ulcer/bleeding (68/812 vs 31/812; p<0.001) in the high-dose methylprednisolone group. Overall, the high-dose methylprednisolone group demonstrated a significantly higher risk of complications (144/812 vs 96/812;OR, 1.66; 95% CI 1.23 to 2.24; p=0.001) than the control group. There was no significant difference in in-hospital mortality between the high-dose methylprednisolone group and the control group (p=0.884). Conclusions Patients receiving high-dose methylprednisolone had a significantly increased risk of major complications, in particular, gastrointestinal ulcer/bleeding. However, high-dose methylprednisolone treatment was not associated with any increase in mortality.

TEXT2TABLE: Medical Text Summarization System Based on Named Entity Recognition and Modality Identification

With the rapidly growing use of electronic health records, the possibility of large-scale clinical information extraction has drawn much attention. It is not, however, easy to extract information because these reports are written in natural language. To address this problem, this paper presents a system that converts a medical text into a table structure. This systems core technologies are (1) medical event recognition modules and (2) a negative event identification module that judges whether an event actually occurred or not. Regarding the latter module, this paper also proposes an SVM-based classifier using syntactic information. Experimental results demonstrate empirically that syntactic information can contribute to the methods accuracy.

Health care costs related to out-of-hospital cardiopulmonary arrest in Japan

OBJECTIVES Although cost analyses for emergency care are essential, data on costs of care for out-of-hospital cardiopulmonary arrest (OHCA) are scarce. The present study aimed to analyze health care costs related to OHCA using a nationwide administrative database in Japan. METHODS Using the Diagnosis Procedure Combination database in Japan, we identified OHCA patients who were transported to 779 emergency medical centres between July and December in 2008 and 2009. We assessed patient survival and discharge status, receipt of specific treatments, and costs of in-hospital care. RESULTS A total of 21,750 OHCA patients were identified. Overall, 59.6% were males, and the average age was 70.3 years. Of them, 1394 (6.4%) resulted in death without attempted resuscitation after hospital arrival (Group A), 14,973 (69.0%) died on admission day despite resuscitation attempts (Group B), 3680 (17.0%) died at ≥2 days after admission despite resuscitation attempts (Group C), 785 (3.6%) survived and were discharged to home (Group D) and 873 (4.0%) survived and discharged to other than home (Group E). The median total costs were

Impact of surgical intervention timing on the case fatality rate for Fournier's gangrene: an analysis of 379 cases

434,

High-volume surgeons in regard to reductions in operating time, blood loss, and postoperative complications for total hip arthroplasty

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Relationship between hospital volume and operative mortality for liver resection: Data from the Japanese Diagnosis Procedure Combination database

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Impact of hospital volume on postoperative complications and in-hospital mortality after musculoskeletal tumor surgery: analysis of a national administrative database.

28,097 and