The mortality rate of severely ill patients treated with venoarterial extracorporeal membrane oxygenation (VA-ECMO) remains unknown because of differences in patient background, clinical settings, and sample sizes between studies. We determined the in-hospital mortality of VA-ECMO patients and the proportion weaned from VA-ECMO using a national inpatient database in Japan. Patients aged ≥19 years who received VA-ECMO during hospitalization for cardiogenic shock, pulmonary embolism, hypothermia, poisoning, or trauma between 1 July 2010 and 31 March 2013 were identified, using The Japanese Diagnosis Procedure Combination national inpatient database. The primary outcome was in-hospital mortality and the secondary outcome was the proportion weaned from VA-ECMO. A total of 5263 patients received VA-ECMO during the study period. The majority of patients had cardiogenic shock (n = 4,658). The number of patients weaned from VA-ECMO was 3389 (64.4 %) and in-hospital mortality after weaning from VA-ECMO was 1994 (37.9 %). In-hospital mortality without cardiac arrest in the cardiogenic shock group was significantly lower than that in patients with cardiac arrest (70.5 % vs. 77.1 %, p <0.001). In the multivariable logistic regression including multiple imputation, higher age and greater or smaller body mass index were significantly associated with in-hospital mortality, whereas hospital volume was not associated with such mortality. The present nationwide study showed high mortality rates in patients who received VA-ECMO, and in particular in patients with cardiogenic shock and in patients with cardiac arrest. Weaning from VA-ECMO did not necessarily result in survival. Further studies are warranted to clarify risk-adjusted mortality of VA-ECMO using more detailed data on patient background.

Chronic obstructive pulmonary disease (COPD) is a major cause of mortality worldwide. Patients with COPD frequently have systemic comorbidities that often require unscheduled hospitalization for exacerbation and deterioration of physical conditions, and can have a poor prognosis. We verified factors affecting patients’ short-term mortality, using a national inpatient database in Japan. We retrospectively collected data for COPD patients (age: >40 years) with emergency admission between July 2010 and March 2013, using the Diagnosis Procedure Combination database. We performed multivariate logistic analyses fitted with a generalized estimating equation to assess factors associated with all-cause in-hospital mortality. A total of 177,207 patients (mean age: 77.5 years; males: 72.9%) were identified. All-cause in-hospital death occurred in 23,614 patients (13.7%). Higher mortality was associated with older age, male sex, lower body mass index, more severe dyspnea, lower level of consciousness, and worse activities of daily life. Higher mortality was also associated with comorbid conditions, including bacterial pneumonia, aspiration pneumonia, interstitial pneumonitis, pulmonary embolism, respiratory failure, lung cancer, heart failure, cerebral infarction, liver cirrhosis, and chronic renal failure. Our study demonstrated that all-cause in-hospital mortality in patients with COPD who required emergency hospitalization was associated with deteriorated general conditions and comorbidities at admission. Physicians should take into account these prognostic factors to choose better treatment options for COPD patients.

In this study we used nationwide population based data to compare perioperative outcomes, including severe bladder injury, between monopolar and bipolar transurethral resection of bladder tumors. Data of patients with clinical T2 or less bladder cancer who underwent monopolar or bipolar transurethral bladder tumor resection were collected from 788 hospitals in the Japanese Diagnosis Procedure Combination database 2007-2012. One-to-one propensity score matching was performed. End points assessed were severe bladder injury requiring placement of a drainage tube or repair surgery within 3 postoperative days, hemostasis procedures consisting of clot removal or transurethral coagulation within 3 postoperative days, transfusion, other complications, anesthesia duration, postoperative length of stay and total costs. Multivariate analyses compared outcomes of bipolar and monopolar transurethral bladder tumor resection with gender, age, Charlson comorbidity index, clinical stage, hospital volume and hospital academic status as covariates. A total of 8,188 pairs were generated. Compared with monopolar transurethral bladder tumor resection, bipolar resection was associated with a significantly lower incidence of severe bladder injury (0.3% vs 0.6%, OR 0.57), other complications (4.6% vs 5.8%, OR 0.78), slightly shorter postoperative stay (mean 6.4 vs 6.7 days, difference -3.3%) and slightly lower total costs (mean $4,628 vs $4,727; difference -1.1%, all p <0.05). There were no differences in postoperative hemostasis procedures, transfusion and anesthesia duration. Bipolar transurethral bladder tumor resection was associated with a substantially lower incidence of several perioperative complications including severe bladder injury. The findings support the benefit of bipolar transurethral bladder tumor resection over monopolar resection in real-world clinical practice.