Keywords analysis of the Journal of the Korean Society of Emergency Medicine using text mining

OBJECTIVE: Data mining extracts meaningful information from large datasets. In this study, text mining techniques were used to extract keywords from the Journal of the Korean Society of Emergency Medicine, and the change trend was examined. METHODS: The rvest package in R was used to extract all papers published in the Journal of the Korean Society of Emergency Medicine from 2006 to 2016 that could be searched online. Among them, 3,952 keywords were extracted and studied. Using the selected keywords, the corpus was formed by refining keywords that did not correspond to MeSH (Medical Subject Headings) or were misspelled and had similar meanings based on agreement of researchers. Using the refined keywords, the frequencies of the keywords in the first and second halves of the studies were calculated and visualized. RESULTS: Word Cloud revealed that emergency medical service and cardiopulmonary resuscitation (CPR) were most frequently mentioned in both the first and second halves of the studies. In the first half, ultrasonography, stroke, poisoning, injury, and education were frequently mentioned, while in the second half, poisoning, injury, stroke, acute, and tomography were frequently mentioned. A pyramid graph revealed that the frequencies of emergency medical service and CPR were commonly high. CONCLUSION: Core keywords of the Journal of the Korean Society of Emergency Medicine were analyzed for correlations and trends. Changes in study topics according to key topics of interest and period were visually identified.

Subxiphoid Incisional Hernia Development after Coronary Artery Bypass Grafting

BACKGROUND: Median sternotomy can weaken the upper abdominal wall and result in subxiphoid incisional hernia. We evaluated risk factors associated with the development of subxiphoid incisional hernias after coronary artery bypass grafting (CABG). MATERIALS AND METHODS: Of 1,656 isolated CABGs performed between January 2001 and July 2010, 1,599 patients who were completely followed up were analyzed. The mean follow-up duration was 49.5+/-34.3 months. Subxiphoid incisional hernia requiring surgical repair developed in 13 patients (0.8%). The hernia was diagnosed 16.3+/-10.3 months postoperatively, and hernia repair was performed 25.0+/-26.1 months after the initial operation. Risk factors associated with the development of subxiphoid incisional hernia were analyzed with the Cox proportional hazard model. RESULTS: Five-year freedom from the hernia was 99.0%. Univariate analysis revealed that female sex (p=0.019), height (p=0.019), body surface area (p=0.046), redo operation (p=0.012), off-pump CABG (p=0.049), a postoperative wound problem (p=0.041), postoperative bleeding (p=0.046), and low cardiac output syndrome (p<0.001) were risk factors for the development of the hernia. Multivariable analysis showed that female sex (p=0.01) and low cardiac output syndrome (p<0.001) were associated with subxiphoid hernia formation. CONCLUSION: Female sex and postoperative low cardiac output syndrome were risk factors of subxiphoid hernia. Therefore, special attention is needed for patients with high-risk factors.

Correlation Between the Osmolar Gap and Serum Ethanol Level and the Accuracy of Estimated Ethanol Level in Trauma Patients and Non-Trauma Patients

PURPOSE: The osmolar gap increases in proportion to the ethanol level. Some previous studies have shown that the correlation between the osmolar gap and the ethanol level is weak in trauma patient by using an indirect comparison with other patients. We conducted a direct comparison of the correlation of the osmolar gap to the ethanol level between trauma patients and non-trauma patients. We also analyzed the accuracy of the estimated ethanol level between the two groups. METHODS: The research candidates were adult patients who had visited the emergency department of our hospital from December 2003 to November 2008. By using a retrospective chart review, we classified them into three subgroups: non-trauma without shock, trauma without shock, and trauma with shock. In each group, we compared the correlation between the osmolar gap and the measured ethanol level, and we analyzed the accuracy of the estimated ethanol level by using Lin's concordance correlation coefficient. RESULTS: Four hundred forty-seven patients were enrolled in this study. For correlation of the osmolar gap and the measured ethanol level, Pearson's correlation coefficient was 0.916 in all patients, 0.939 in non-trauma without shock patients, 0.917 in trauma without shock patients, and 0.844 in trauma with shock patients. In the analysis of the accuracy of the estimated ethanol level by using Lin's concordance correlation coefficient, the accuracy in trauma with shock patients was lower than that in non-trauma without shock patients. CONCLUSION: We found that the correlation between the osmolar gap and the measured ethanol level in the patient group with trauma was lower than it was in the patient group without trauma. Moreover trauma patients with shock had a lower accuracy of the estimated ethanol level than non-trauma patients.