Norimichi Hirahara

Models predicting the risks of six life-threatening morbidities and bile leakage in 14,970 hepatectomy patients registered in the National Clinical Database of Japan

Abstract To construct a robust morbidity risk-prediction model based on a Japanese nationwide web-based database of patients who underwent liver surgery. Although liver resection has become safer, patient mortality and morbidity still occur. This study investigated postoperative morbidity risks in patients who underwent hepatectomy in Japan at institutions registered in the National Clinical Database. This analysis involved 14,970 patients who underwent hepatectomy of more than 1 section, except for left lateral sectionectomy, during 2011 and 2012 at 1192 hospitals in Japan. Patients were randomized into 2 subsets, with 80% of patients analyzed for model development and the remaining 20% for model validation. Rates of 90-day inhospital mortality and overall morbidity were 3.7% and 25.7%, respectively. Rates of surgical site infection and bile leakage were 9.0% and 8.0%, respectively, but these morbidities showed little association with mortality. Rates of nonsurgical complications, including postoperative transfusion over 5 units, unexpected intubation, renal failure, cardiac events, septic shock, and postoperative pneumonia, ranged from 0.2% to 2.6%. These complications were highly associated with mortality, suggesting they were life-threatening. Risk models for morbidity yielded high C-indices for transfusion of over 5 units (0.758), unplanned intubation (0.755), renal failure (0.80), cardiac events (0.779), septic shock (0.783), pneumonia (0.768), and bile leakage (0.676). Preoperative parameters/comorbidities can accurately predict life-threatening complications after hepatectomy. These models allow early identification of patients at risk of mortality and may be useful in deciding on surgical interventions and in improving surgical quality.

Comparison of National Operative Mortality in Gastroenterological Surgery Using Web-based Prospective Data Entry Systems

AbstractInternational collaboration is important in healthcare quality evaluation; however, few international comparisons of general surgery outcomes have been accomplished. Furthermore, predictive model application for risk stratification has not been internationally evaluated. The National Clinical Database (NCD) in Japan was developed in collaboration with the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP), with a goal of creating a standardized surgery database for quality improvement. The study aimed to compare the consistency and impact of risk factors of 3 major gastroenterological surgical procedures in Japan and the United States (US) using web-based prospective data entry systems: right hemicolectomy (RH), low anterior resection (LAR), and pancreaticoduodenectomy (PD).Data from NCD and ACS-NSQIP, collected over 2 years, were examined. Logistic regression models were used for predicting 30-day mortality for both countries. Models were exchanged and evaluated to determine whether the models built for one population were accurate for the other population.We obtained data for 113,980 patients; 50,501 (Japan: 34,638; US: 15,863), 42,770 (Japan: 35,445; US: 7325), and 20,709 (Japan: 15,527; US: 5182) underwent RH, LAR, and, PD, respectively. Thirty-day mortality rates for RH were 0.76% (Japan) and 1.88% (US); rates for LAR were 0.43% versus 1.08%; and rates for PD were 1.35% versus 2.57%. Patient background, comorbidities, and practice style were different between Japan and the US. In the models, the odds ratio for each variable was similar between NCD and ACS-NSQIP. Local risk models could predict mortality using local data, but could not accurately predict mortality using data from other countries.We demonstrated the feasibility and efficacy of the international collaborative research between Japan and the US, but found that local risk models remain essential for quality improvement.

Prediction model for complications after low anterior resection based on data from 33,411 Japanese patients included in the National Clinical Database

Background: Low anterior resection is associated with a relatively high incidence of postoperative morbidities, including anastomotic leakage and other operative site infections, which sometimes result in postoperative mortality. Therefore, recognition of the incidence and risk factors of postoperative complications following low anterior resection is essential. Methods: Data from the National Clinical Database on patients who had undergone low anterior resection in 2011 and 2012 were retrospectively analyzed. Multiple logistic regression analyses were performed to generate predictive models of postoperative complications. Receiver‐operator characteristic curves were generated, and the concordance index was used to assess the models discriminatory ability. Results: The number of patients who had undergone low anterior resection was 33,411. Seven complications, namely, overall operative site infections except for leakage, anastomotic leakage, urinary tract infection, pneumonia, renal failure, systemic sepsis, and cardiac events, were selected to construct statistical risk models. The concordance indices for the first 2 complications, which were dependent on the operative procedure, were relatively low (0.593–0.625), and the other 5, unrelated to operative procedures, showed high concordance indices (0.643–0.799). Conclusion: This study created the worlds second risk calculator to predict the complications of low anterior resection as a model based on mass nationwide data. In particular, this model is the first to predict anastomotic leakage.

Risk assessment of morbidities after right hemicolectomy based on the National Clinical Database in Japan

Nationwide databases are expected to provide critical data to improve medical practice. The present study used such data to develop risk models for clinically important outcomes after right hemicolectomy based on preoperative risk factors.

Current Surgical Outcomes of Congenital Heart Surgery for Patients With Down Syndrome in Japan

BACKGROUND Current surgical outcomes of congenital heart surgery for patients with Down syndrome are unclear.Methods and Results:Of 29,087 operations between 2008 and 2012 registered in the Japan Congenital Cardiovascular Surgery Database (JCCVSD), 2,651 were carried out for patients with Down syndrome (9%). Of those, 5 major biventricular repair procedures [ventricular septal defect repair (n=752), atrioventricular septal defect repair (n=452), patent ductus arteriosus closure (n=184), atrial septal defect repair (n=167), tetralogy of Fallot (TOF) repair (n=108)], as well as 2 major single ventricular palliations [bidirectional Glenn (n=21) and Fontan operation (n=25)] were selected and their outcomes were compared. The 90-day and in-hospital mortality rates for all 5 major biventricular repair procedures and bidirectional Glenn were similarly low in patients with Down syndrome compared with patients without Down syndrome. On the other hand, mortality after Fontan operation in patients with Down syndrome was significantly higher than in patients without Down syndrome (42/1,558=2.7% vs. 3/25=12.0%, P=0.005). CONCLUSIONS Although intensive management of pulmonary hypertension is essential, analysis of the JCCVSD revealed favorable early prognostic outcomes after 5 major biventricular procedures and bidirectional Glenn in patients with Down syndrome. Indication of the Fontan operation for patients with Down syndrome should be carefully decided.