Purpose We investigated the risk factors for early postoperative complications after gastric cancer surgery. Materials and methods The data from a total of 273 patients with gastric cancer were analyzed by univariate and multivariate analysis. We applied physiological and operative severity score for the enumeration of morbidity and mortality (POSSUM) to compare risk-adjusted surgical outcomes among different surgical units. Results Among the preoperative variables, patient gender, chronic obstructive pulmonary disease, surgical unit, and intraoperative blood loss were independent risk factors for a higher rate of postoperative complications. There were significant differences in complication rates among different surgical units (P=0.001). The observed-to-expected morbidity ratio (O-to-E ratio) ranged from 0.81 to 1.63. Units with low surgical work volume had higher complication rates. Postoperative length of stay was significantly shorter (P=0.000) and the rate of moderate and severe complications was significantly lower (P=0.001) in specialized unit.Conclusions POSSUM is a valid system for risk-adjusted evaluation of surgical outcomes. We conclude that surgical experience and work volume greatly influence the outcome, with overall surgical outcome in specialized centers superior to that in other units. Hence, gastric cancer surgery should be performed in specialized centers. Risk factors identified in this study need further confirmation by a prospective study involving a larger cohort.

Background: The purpose of this study was to evaluate the necessity of a nasogastric decompression in radical gastrectomy for gastric cancer patients by a prospective randomized controlled trial. Methods: From 2007 to 2009, 161 gastric cancer patients who underwent radical gastrectomy were randomly selected and entered into three groups: tube group (TG), intra-operative tube group (ITG), and no-tube group (NTG). The variables studied among the groups were demographic characteristics, surgical characteristics, postoperative recovery and complications. Results: With respect to demographic and surgical characteristics, there were no significant differences among the 3 groups. The time of the first passage of flatus, tolerance of water intake, liquid diet and semiliquid diet were similar among TG, ITG and NTG. Postoperative hospital stay was increased in patients from TG compared to NTG (11.3 vs. 10.2 days, p = 0.031). The incidence of nausea was significantly higher in TG than in ITG or NTG (64 vs. 36.8 and 29.6%). The overall postoperative complication rate was not significantly different among these groups (20, 15.8 and 20.4% in TG, ITG and NTG, respectively, p = 0.612). Conclusions: Radical gastrectomy can be performed safely without nasogastric decompression for gastric cancer patients. The routine prophylactic nasogastric decompression is unnecessary.

The structure of the centrifugal pump with splitting blades is complex, and the law of the internal flow is not fully grasped. Therefore Reverse Engineering (RE) and numerical simulations of Computational Fluid Dynamics (CFD) are adopted to study the centrifugal pumps with splitter blades. In this process, the law of velocity and pressure distribution of internal flow about the centrifugal pump with splitter blades is preliminary disclosed. In addition, performance prediction was carried out in centrifugal pumps. Comparing to the calculation curve and text characteristic curve, it’s obvious that simulation results are in good agreement with experimental results. The results verify the reliability and feasibility of the research method.