Assessment of duodenal circular drainage operations to treat superior mesenteric artery syndrome

To assess the clinical value of duodenal circular drainage operation to treat superior mesenteric artery syndrome(SMAS). Methods Forty two cases of SMAS were treated with duodenal circular drainage operation from 1959 to 2001. Clinical data were analyzed retrospectively. Results In this group,37 cases were treated with duodenal circular drainage operation,and had good effect after follow- up of 1～15 years,the other 5 cases were first treated with anterior repositioning of the duodenum (1 case),gastrojejunostomy (1 case) ,duodeojejunostomy (2 cases) .subtotal gastrectomy and Billroth Ⅱ gastrqjejunostomy( 1 case), but vomiting was not relieved until duodenal circular drainage operation was performed again. Follow-up of 9～10 years revealed good effect. Conclusion In SMAS, if the reversed peristalsis is stronger and continuous,and vomiting appears frequently, the symptom can not be relieved even if the obstruction of duodenum is removed by operation. The key treatment is the relief of reversed peristalsis. Only the duodenal circular drainage operation could resolve the drainage direction of duodenal content and relieve the symptom of vomiting.

Experimental investigation on the invert stability of operating railway tunnels with different drainage systems using 3D printing technology

In recent years, the invert anomalies of operating railway tunnels in water-rich areas occur frequently,which greatly affect the transportation capacity of the railway lines. Tunnel drainage system is a crucial factor to ensure the invert stability by regulating the external water pressure(EWP). By means of a threedimensional(3D) printing model, this paper experimentally investigates the deformation behavior of the invert for the tunnels with the traditional drainage system(TDS) widely used in China and its optimized drainage system(ODS) with bottom drainage function. Six test groups with a total of 110 test conditions were designed to consider the design factors and environmental factors in engineering practice,including layout of the drainage system, blockage of the drainage system and groundwater level fluctuation. It was found that there are significant differences in the water discharge, EWP and invert stability for the tunnels with the two drainage systems. Even with a dense arrangement of the external blind tubes, TDS was still difficult to eliminate the excessive EWP below the invert, which is the main cause for the invert instability. Blockage of drainage system further increased the invert uplift and aggravated the track irregularity, especially when the blockage degree is more than 50%. However, ODS can prevent these invert anomalies by reasonably controlling the EWP at tunnel bottom. Even when the groundwater level reached 60 m and the blind tubes were fully blocked, the invert stability can still be maintained and the railway track experienced a settlement of only 1.8 mm. Meanwhile, the on-site monitoring under several rainstorms further showed that the average EWP of the invert was controlled within 84 k Pa, while the maximum settlement of the track slab was only 0.92 mm, which also was in good agreement with the results of model test.

Effect of preoperative biliary drainage on outcome of classical pancreaticoduodenectomy

AIM: To investigate the role of preoperative biliary drainage (PBD) in the outcome of classical pancreaticodu odenectomy. METHODS: A 10-year retrospective data analysis was performed on patients (n = 48) undergoing pancreaticoduodenectomy from March 1994 to March 2004 in department of surgery at SMS medical college, Jaipur, India. Demographic variables, details of preoperative stenting, operative procedure and post operative complications were noted. RESULTS: Preoperative biliary drainage was performed in 21 patients (43.5%). The incidence of septic complications was significantly higher in patients with biliary stent placement (P < 0.05, 0 vs 4). This group of patients also had a significantly higher minor biliary leak rate. Mortality and hospital stay in each group was comparable. CONCLUSION: Within this study population the use of PBD by endoscopic stenting was associated with a high incidence of infective complications. These findings do not support the routine use of biliary stenting in patients prior to pancreatico-duodenectomy.

Combined urethral and suprapubic catheter drainage improves post operative management after open simple prostatectomy without bladder irrigation

AIM To compare outcomes after open simple prostatectomy without bladder irrigation, in subjects drained by combined 2-way urethral catheter and suprapubic catheter(SPC) vs those drained by 2-way urethral catheter only.METHODS A total of 84 participants undergoing Freyer's simple prostatectomy over an 18-mo period were randomized into 2 groups(n=42). Subjects in group 1 were managed with 2-way urethral catheter and in situ 2-way SPC while subjects in group 2 had a 2-way urethral catheter drainage only. In group 1 subjects, the SPC was spigotted and only used for drainage if there was clot retention. The primary outcomes were number of clot retention episodes, and number of clot retention episodes requiring bladder syringe evacuation. Other secondary outcomes evaluated were blood loss, requirement of extra analgesics, duration of surgery, hospital stay and presence or absence of post-op complications. RESULTS The mean age in the groups was 65.7(± 7.6) in group 1 vs 64.8(±6.8) in group 2.The groups were similar with respect to age, prostate specific antigen, prostate volume, blood loss, duration of surgery, blood transfusion and overall complication rate. However statistically significant differences were observed in clot retention episodes between group 1 and 2:0.8(±1.5)vs3.5(±4.4), P<0.000, clot retention episodes requiring evacuation with bladder syringe 0.4(± 0.9) vs 2.6(± 3.8), P = 0.001, requirement of extra analgesics 0.4(±0.5)vs4.0(±1.5), P<0.000 and duration of admission 8.6d(± 1.2) vs 7.3 CONCLUSION Subjects drained with a combination of urethral and SPCs have fewer clot retention episodes and reduced requirement of extra analgesics but slightly longer hospital stay.

Assessment of duodenal circular drainage in treatment of superior mesenteric artery syndrome

AIM: To assess the clinical value of duodenal circular drainage for superior mesenteric artery syndrome (SMAS). METHODS: Forty-seven cases of SMAS were treated with duodenal circular drainage from 1959 to 2001. Clinical data were analyzed retrospectively. RESULTS: In this group, good effects were achieved in 39 cases treated with duodenal circular drainage after 2-15 years of follow-up. The other eight cases were first treated with anterior repositioning of the duodenum (two cases), duodenojejunostomy (five cases), subtotal gastrectomy and billroth Ⅱ gastrojejunostomy (one case), but vomiting was not relieved until duodenal circular drainage was performed again. A follow-up study of 8-10 years revealed satisfactory results in these eight patients. CONCLUSION: In SMAS, if the reversed peristalsis is strong and continuous, and vomiting occurs frequently, the symptom can not be relieved even if the obstruction of duodenum is removed surgically. The key treatment is the relief of reversed peristalsis. The duodenal circular drainage can resolve the drainage direction of duodenal content, thus relieving the symptom of vomiting.

Results of Fontan in Patients with Apicocaval Juxtaposition or/and Separated Hepatic Venous Drainage

Objective:Modifications of the Fontan operation,which are also known as total cavopulmonary connection(TCPC),are widely applied for patients with functionally univentricular hearts(FUH).Herein,we summed up the different surgical pathways and clinical outcomes in FUH patients with apicocaval juxtaposition(ACJ)or/and separated hepatic venous(SHV)drainage.Methods:Between January 2009 and December 2019,123 patients who undergone TCPC in our institute were included in this retrospective study.We have included 70 patients with ACJ(Group 1)and 53 patients with SHV(Group 2).Moreover,Group 2 included 17 cases combing with ACJ(32.1%).In Group 1,three different TCPC methods were conducted.While 45 cases were conducted with the extracardiac conduit-TCPC(EC-TCPC)method,24 cases used the intracardiac conduit-TCPC(IC-TCPC)method,and only one case used the lateral tunnel-TCPC(LT-TCPC).In Group 2,four TCPC methods were conducted on patients.Forty cases used the EC-TCPC-common open technique,6 cases with IC-TCPC technique,4 cases with LT-TCPC,and 3 cases with intra-extracardiac conduit-TCPC(IEC-TCPC).Results:There were 7 patients in Group 1 and 14 patients in Group 2 who required early re-operation during hospitalization(p<0.05).Postoperative mean pulmonary artery pressure(mPAP)greater than 15 mmHg emerged as a predictor for early re-operation(p<0.01)and early death(p<0.001)in univariate analysis.Conclusions:TCPC can be performed in these patients and shows beneficial results.Under the Fontan principle of connecting systemic venous to the pulmonary vasculature unimpededly,surgeons should carefully evaluate three components when choosing for the surgical technique:The distance between inferior vena cava(IVC)and the apex;the site of the vertebrae relative to the ACJ;the distance between ACJ and SHV if coexisting.However,the technique should be altered when the postoperative mPAP was greater than 15 mmHg.

Novel and supplementary management of pancreatic fluid collections:Endoscopic ultrasound-guided drainage

AIM To compare efficacy and safety of endoscopic ultrasound (EUS)-guided and surgical drainage in pancreatic fluid collection management.METHODS Data were obtained retrospectively from January 2012 to December 2016.Patients with pancreatic fluid collection were performed EUS-guided or surgical procedure.Main outcome measures including clinical efficiency,complication,duration of procedures,hospital stay and cost were analyzed.RESULTS Thirty-six patients were enrolled into the study,including 14 in endoscopic group while 22 in the surgical group.Twelve (86%) patients were treated successfully by endoscopic approach while 21 (95%) patients benefited through surgical procedure.Endoscopic treatment had higher recurrence and complication rates than surgery,resulting in more re-interventions.Meanwhile,duration of procedure,hospital stay and cost were significantly lower in endoscopic group.CONCLUSION Both approaches were effective and safe.EUS-guided approach should be the first-line treatment in mild and simple cases,while surgical approach should be considered as priority in severe and complex cases.

肠外瘘的外科阶段治疗策略

目的:总结肠瘘不同阶段的治疗经验及分期手术策略在肠瘘确定性手术治疗中的应用。方法:采用回顾性病例数据,收集2016年1月—2019年12月清华大学附属北京清华长庚医院收治的255例肠瘘患者的临床资料,包括患者年龄、性别、原发疾病、致瘘原因、瘘的部位、瘘的数量、瘘的性质、瘘发生到就诊时间、肠瘘诊断评估方式、营养风险、营养支持方式、入院感染状态等进行初步总结。根据肠瘘病理生理特点进行肠瘘阶段治疗:肠瘘急性阶段-肠瘘稳定阶段-肠瘘确定性手术阶段。肠瘘确定性手术分期治疗:I期手术和分期手术。并分析各个阶段治疗策略和治疗效果。结果:肠瘘急性阶段(141例),局部感染患者与严重感染患者之间的腹腔脓肿处理方式有明显差异(P=0.023),损伤控制外科手术适合严重感染患者。141例均进入肠瘘稳定阶段,其中112例患者接受全过程治疗,28例放弃,1例死亡。112例完整治疗患者中,75例治愈(治愈率83.7%),37例保守无效进入肠瘘确定性手术阶段;联合114例外院保守无效肠瘘患者;共计151例进入肠瘘确定性手术阶段;其中134例行Ⅰ期手术,17例行分期手术。151例患者手术治疗的总体结局,138例治愈(治愈率为91.4%)。结论:根据肠瘘患者的发生和病理生理,正确归入肠瘘急性阶段、肠瘘稳定阶段或肠瘘确定性手术阶段并进行相应的治疗至关重要。另外,合理的手术时机和分期手术策略也是手术治疗肠瘘的关键所在。

小型排水户合规排水难点及解决措施

小餐饮、洗车店及小型诊所等小型排水户数量多、分布散,由于对环保的重视程度不够,同时缺乏相应的专业知识,为降低经营成本,可能存在违规排污的行为,对城市环境造成负面影响。为有效解决小型排水户无证排水的历史遗留问题,规范小型排水户排水行为,对全市75家不同类型的小型排水户开展调查工作,其中包括对排水资料、排水出路、排水量、排水性质、排水方式、排放口及排水设施等内容的调查。根据调查结果,将小型排水户存在的主要排水问题归纳为5类,并对小餐饮、洗车店及小型诊所(含动物诊疗)3类小型排水户的主要问题进行细化研究,总结出小型排水户合规排水的主要难点及对应措施,帮助小型排水户达成合规化排水的目标。本次调查对保障城市水环境、优化营商环境均具有一定的社会效益。

基于在线监测数据的排水管道运行规律识别

随着在线监测技术的发展,排水管道水位和水量在线监测得到越来越多的应用。以西南某城市主干管的在线监测数据为例,建立了流程化和标准化的分析方法。通过液位与流量的旱天规律曲线图和场次降雨散点图,充分挖掘数据信息并进行集中表达。结果表明,应用此分析方法,可识别管道在旱天和雨天的水位负荷、冒溢风险、水量规律、转输能力等特征,为事故预警、风险防控、水量核算、管网调度提供支撑。

基于高强度农田排水的人工快速渗滤系统结构及运行管理优化研究

【目的】通过研究不同填料组合人工快速渗滤系统(CRI)对高排水强度、低污染浓度农田排水的净化效果,优选出适宜的填料组合及运行条件,为实际工程提供理论支持。【方法】试验设置5个污染负荷水平(即不同氮磷浓度和泥沙量),3个水力负荷水平;在每个污染负荷水平下,通过控制渗滤柱进出水量来控制不同水力负荷;并采用高通量测序分子生物学技术手段,考察系统中微生物群落结构与功能的关系,进而分析系统中不同填料组合下生物脱氮除磷效能与机制。【结果】①不同填料填装高度对各污染物的净化效果总体表现为80 cm>60 cm>40 cm;各填料组合对各污染物净化效果以粗沙、活性炭、黏土陶粒体积比为3∶2∶2、分层填装、填装高度80 cm组合(S3)最好,对总氮(TN)、总磷(TP)、氨氮(AN)、泥沙的净化率分别达到53.26%、82.51%、68.18%和78.43%。②不同污染负荷下,TN净化效果以污染负荷水平2 mg/L(W1)最好,与其他污染负荷水平呈极显著差异,其次为污染负荷水平4 mg/L(W2),净化率分别达56.70%和42.78%;AN、泥沙净化效果均以污染负荷水平W2(AN 4 mg/L、泥沙0.2 g/L)最好,净化率分别达到48.46%和81.61%,但TP净化效果各污染负荷水平间无明显差异。③随着水力负荷增大,渗滤柱对TN、TP、AN和泥沙去除率逐渐下降;在水力负荷28 L/(m^(2)·min)(T1)水平下,渗滤柱对TN、TP、AN、泥沙等各污染物的净化效果均最好,净化率分别达到48.80%、78.51%、54.88%和79.77%。④渗滤柱不同位置菌群物种数下部更多,而菌群多样性上部更高;相似填料组合其微生物群落结构具有较高的相似性;Proteobacteria(变形菌门)丰度最高,其次是Actinobacteria(放线菌门)、Firmicutes(厚壁菌门),对氮的去除起到了关键作用。【结论】人工快速渗滤系统填料填装高度80 cm,分层填装,粗沙、活性炭、黏土陶粒填料比例为3∶2∶2,适用于处理高强度农田排水,表现出较好的净化效果,对污染负荷TN为2 mg/L,AN为4 mg/L,泥沙为0.1~0.3g/L,水力负荷为28 L/(m^(2)·min)净化效果最佳,并可承受较大变幅的TP污染负荷。

雨水系统运行回归设计状态是城市雨天污染控制的关键

雨天排水污染是影响当前城市水环境质量提升的限制性因素,雨水系统运行回归设计状态是城市雨天污染控制的关键。围绕雨天排水污染控制这一难题,从雨水系统设计状态涵义、雨水系统如何回归设计状态及回归设计状态过程中的关键控制举措三方面展开论述。遵循现行国家标准设计的完全分流制雨水系统,按照设计状态运行可以有效实现入河污染控制;污染动态溯源排查整治让雨水和污水“各行其道”、强化城市排水管渠检测修复保障运行水位可从技术手段上使雨水系统回归设计状态,长效管理和智能运维是雨水系统保持设计状态的关键;同步提出雨水系统回归设计状态过程中可采取基于雨水口截污源头减排、合流制区域排水户雨天污水排放管控等措施。

橡胶坝积气和尾水故障分析及抽排系统设计

充水式橡胶坝在充水后坝袋内顶部常有积气无法彻底排除,塌坝泄洪时坝袋底部常有尾水无法彻底排除。为解决这两项常见故障,在分析故障产生的原因及可能引发的一系列后果的基础上,发明了橡胶坝积气和尾水抽排系统,提出了抽排管路、抽排动力装置和控制系统的概念设计原理和方法。通过典型应用实例验证了该系统能有效排除积气和尾水故障及其引发的一系列问题,保障橡胶坝工程能够以最大高度蓄水,以最大过水断面泄洪,为橡胶坝工程精细化设计及改进传统设计方案提供了创新思路。

市政排水系统厂站网一体化调度应用

随着城市化进程的加速,城市排水系统的运行面临着越来越大的挑战。传统的排水系统管理模式存在调度决策支撑不足、效率较低等问题,无法满足现代排水系统精细化管理的需求。探索排水系统厂站网一体化调度模式,对于提高排水系统实际运行效率和管理水平具有重要意义。对上海市某片区市政排水系统厂站网一体化调度应用进行研究,搭建厂站网一体化调度平台,集成排水设施基础数据、物联感知监测数据以及水雨情气象数据数据库,以污水管网干线模型为计算引擎,实现排水运行日常监管、一体化调度支持实际应用等功能,为排水系统高效平稳运行提供支撑。

杭州三堡排涝工程运行管理实践与思考

随着极端天气事件的增多,城市防灾减灾工作面临着巨大的挑战。杭州三堡排涝工程建成以来经历了8个汛期的安全运行,有力提升了区域防洪排涝能力。为进一步发挥杭州三堡排涝工程的防灾减灾功能和社会综合效益,通过对其防洪排涝、泵站运行、水文化水生态融合等工程运行管理实践的分析,提出推进流域骨干防洪工程建设,完善泵站相关技术规范,促进水工程与水文化深度融合等方面的合理建议,可为其他城市强排泵站的建设和管理提供借鉴。

煤矿井下排水系统的优化设计

针对煤矿井下排水系统自动化程度低、劳动强度大、可靠性差、设备检修难等问题,通过对现有设施、设备进行优化改造,设计了一种井下排水智能控制系统,实现了全自动化控制、远程监控、无人值守、水泵自动轮换等功能,确保煤矿井下排水系统的安全。实践证明,该系统设计合理,控制方便,运行稳定可靠,故障率低,降低了系统能耗,提高了煤矿生产的安全性和效率。

基于CIM的数字孪生排水系统研究与设计

针对雨季内涝、污水外溢、夜间偷排等排水问题,基于监测一张图思路,建立基于城市信息模型(CIM)的数字孪生排水系统,形成从水源至管网厂站终到河流的全过程监测管控,实现排水的全时监测与战时预警预报功能,及时发现运行状况风险并快速对异常事故进行追踪,提升排水管理部门的应急处理能力。

有限空间临排中导管施工创新研究

中导管是管道非开挖修复施工中常用的一种临时导流设施,布设于待修复管道中,用于导流管道内水流,以创造管道修复干仓条件。由于管道内环境特殊,中导管施工难度极大。以某城市老旧雨污水合流管道修复项目为例,分析、研发了一种新型中导管施工方法,通过T形支腿、导轨、走道板、运输小车、起吊支架,解决了中导管在运输、拼接、拆除等方面的施工难题,提升了施工效率,可为类似工程提供参考。