Drainage Management Research Articles

Spatial characterization of total salt in non-saline soil solutions through electromagnetic induction

Apparent electrical conductivity (ECa) surveys can indirectly spatially characterise total salt in saline soil solutions, i.e., electrical conductivity of a saturated paste extract (ECe). Due to complexity of ECa-readings a 10-step protocol, including an analytical procedure (Dual Pathway Parallel Conductance, DPPC) and software (Electrical conductivity Sampling Assessment and Prediction), have been developed to facilitate with the process. Studies where ECa readings have been used to spatially characterise ECe in soil solutions below 2 dS m−1 (non-saline) are limited to non-existing. The aim was to collectively use above-mentioned tools to determine the success with which ECe can be spatially characterised in non-saline soil solutions with variable and uniform texture across the field. Dataset 1 consisted of ECe, gravimetric moisture and clay measurements from 277 grid sampling sites across 320 ha (seven fields). Dataset 2 contained a mean 443 ECa readings ha−1 together with measurements of ECe, clay, gravimetric moisture, and bulk density from 12 ECa-directed sampling sites per field. Dataset 1; the r between calculated ECa (ECac) and ECe at all fields were >0.9. Dataset 2; deep ECa readings (i.e., 1 m coil separation for both dipole orientations) remained stable during surveys (not true for shallow readings). At 3 fields, uniform in depth and spatially in terms of clay content (±10% clay), relatively low ECa readings (±50 mS m−1) significantly correlated with low ECe values (<1.5 dS m−1). Hence, proactive management of excessive irrigation-induced drainage and salt leaching by spatial monitoring of ECe in non-saline soil, spatially uniform in texture, through electromagnetic induction is conceivable.

Drain management after pancreas surgery

Drain management after pancreas surgery

Drain management following difficult laparoscopic cholecystectomy for acute cholecystitis: A propensity matched comparative study

Drain management following difficult laparoscopic cholecystectomy for acute cholecystitis: A propensity matched comparative study

STORM WATER MANAGEMENT BY NEW TECHNIQUES

Abstract - Urbanization and climatic change have adverse effects on the changes of natural hydrological regime, which results in more frequent floods and landslides. Besides the increased quantity of the storm water that drainage channels have to store, negative consequences of urbanization are also evident through increased pollution of runoff stormwater. India has been witnessing devastating floods. Due to lack of drainage systems, the larger cities are more prone to frequent flooding. The drainage system and management should be adapted to these changes so that the adverse effects of hydrological conditions of runoff and storm water pollution in the urban and developing areas are mitigated. This project aims at presenting challenges and opportunities for the better storm water management practices in these areas.

The Application of AHP to Determine the Priority Drainage System on Flood Mitigation in Surabaya – Indonesia

Natural disasters are common worldwide, especially in tropical countries. Floods are one such frequent disaster that occur in the tropical country of Indonesia. Floods cause disasters in many vulnerable societies living in the area. Therefore, it is necessary to conduct risk assessments for flood mitigation. The objective of this research is to support decision-making for flood risk assessment by selecting priority sub-systems. The research was conducted in Surabaya, East Java, and Indonesia. The Surabaya drainage system is divided into five districts consisting of several sub-systems facing inundation problems. This causes challenges for the government in selecting which sub-systems should be prioritized to overcome these problems. Consequently, a rank priority for sub-systems is required. This research validated whether the Analytics Hierarchy Process (AHP) method was applicable and appropriate to weight priority factors to select the priority drainage system. It weighs historical flood data by considering several criteria related to floods, consisting of flood hazards, social economics, and the environment. Flood hazard is defined as the severity level of flooding indicated by three indicators: inundation area, inundation depth, and inundation duration. Social-economics is a criterion covering population density and land use types consisting of residential areas, commercial and services areas, public facilities, industrial areas, port areas, and mix used development support areas. Environment is a criteria indicated by green open space, flood-prone areas, watershed catchment areas, and storage areas. The weighting result convinced the decision makers as to the related parameters which should be considered in order to support appropriate and effective flood mitigation. Further, due to budget constraints, the results of the research can be used to assist the municipal government in selecting which drainage system should be prioritized for management. The AHP result reveals that the priority drainage systems are Wonorejo sub system (Jambangan district), Greges sub system (Genteng district), Kedurus sub system (Wiyung district), Kalibokor sub system (Gubeng district), and Tambak Dono sub system (Tandes district). The result was confirmed to several respondents from Department of Public Works, Highways, and Drainage Management involved with the drainage system in Surabaya. It is indicates that the AHP results mostly are applicable to the existing condition.

204 Identifying Barriers to and Strategies for Implementing Same-Day Discharge after Mastectomy

OBJECTIVES/GOALS: Same-day discharge (SDS) after mastectomy without reconstruction (MwoR) is cost-effective with equivalent complications rates when compared to patients discharged the day after surgery. Despite this, facilities SDS rates after MwoR vary from &lt;10%-80% (20% overall). We aimed to explore barriers to and strategies for implementing SDS after MwoR. METHODS/STUDY POPULATION: We conducted semi-structured interviews with surgeons currently performing MwoR and practicing in the state of Michigan. Recruitment was done through purposeful and snowball sampling methods. Interviews ranged from 40-60 minutes in length. The interview guide was based on the Tailored Implementation of Chronic Disease framework. Interviews were transcribed then analyzed by 3 independent reviewers. A framework matrix was created to identify common themes. RESULTS/ANTICIPATED RESULTS: Participants (n=15) included general surgeons, breast surgeons, surgical oncologists, and both university and non-university affiliated practices were represented. Surgeons either discharged patients the same-day or the day after MwoR. All surgeons who didnt routinely discharge patients the day of surgery (n=9) believed their facility had the resources to implement this practice and it would be safe for most patients. Identified barriers to same-day discharges included provider preoperative expectation setting, patient anxiety about managing their wound drain, and practice standards at their facility. Potential strategies for implementation included incorporating drain teachings with patients before surgery and explaining the benefits of same-day discharge with other providers at your facility. DISCUSSION/SIGNIFICANCE: We identified novel barriers to same-day discharge after MwoR. These barriers are potentially targetable with interventions addressing patient anxiety surrounding drain management, and education of providers across the care continuum.

-8cm H2 O, the new paradigm in chest drain management following thoracoscopic lung resection?

BackgroundChest drain suction of −20 cm H2O has been used universally after lung resection. After introducing new guidelines,−8 cm H2O was used routinely for all non‐pneumonectomy, thoracoscopic lung resections. We conducted a review to determine outcomes and safety.MethodsAfter introduction of the guidelines data were collected in the study institutions' thoracic surgical database and subsequently analysed.ResultsA total of 155 patients underwent thoracoscopic lung resection. Mean patient age was 61.5 ± 13.6 years. Video‐assisted thoracoscopic surgery was performed in 92.2% (144/155) of patients and robotically‐assisted thoracoscopic surgery was performed in 7.8% (12/155) of patients. Lobectomy was performed in 56.8% (88/155) of patients, segmentectomy was performed in 11.6% (18/155) of patients and wedge resection was performed in 31.6% (49/155) of patients.Median ICC duration time was 1 day (IQR 1–3). Median length of stay was 3 days (IQR 2–6). For patients undergoing lobectomy median ICC time was 2 days (IQR 1–4.5) and median length of stay was 3.5 days (IQR 2–7), for segmentectomy median ICC time was 1 day (IQR 1–5) and median length of stay was 2 days (IQR 1–5) and for wedge resection median ICC time was 1 day (IQR 1–1) and median admission time was 2 days (IQR 1–4).ConclusionA suction level −8 cm H2O is safe to use for thoracoscopic lung resections from day 0 post‐operatively. A dedicated, prospective study comparing levels of suction should be performed.

Novel Calculator to Estimate the Risk of Clinically Relevant Postoperative Pancreatic Fistula Following Distal Pancreatectomy

BackgroundDrain management algorithms are based on studies that predict clinically relevant postoperative pancreatic fistula (CR-POPF) using drain fluid amylase level on POD1 (DFA1). These studies are focused on pancreaticoduodenectomy which is inherently different than distal pancreatectomy. Moreover, the change of DFA between POD1 and POD3 (ΔDFA) is underutilized despite its importance in predicting CR-POPF. We sought to generate a calculator that estimates the risk of CR-POPF following distal pancreatectomy. MethodsThe 2014–2018 pancreas-targeted ACS-NSQIP database was used to identify patients who underwent elective distal pancreatectomy. Models to predict CR-POPF were constructed using DFA1 with/without ΔDFA. The fittest model was used to construct a calculator. ResultsOut of 12,042 distal pancreatectomies, 692 patients met the study’s inclusion criteria. The risk of CR-POPF was 15.9% in the included cohort versus 14.8% in the excluded one (P = 0.421). The predictors of the CR-POPF were age, operative time, DFA1, and ΔDFA. Adding ΔDFA decreased the Akaike’s information criterion of the model (507.7 vs 544.7)—indicating a significantly better model fit—and improved the cross-validated area under the curve from 0.731 to 0.791. An easy-to-use calculator was created for surgeons to estimate the risk of CR-POPF based on the abovementioned variables. A sensitivity/specificity table was created at various cutoffs to direct clinical decision-making with respect to early drain removal. ConclusionsThis study highlights the importance of ΔDFA, in addition to DFA1, in predicting CR-POPF. The provided calculator will facilitate predicting CR-POPF and postoperative drain management following distal pancreatectomy.

Effect of Drain Output on the Timing of Closed Suction Drain (CSD) Removal After Head and Neck Surgery.

Background: A closed suction drain (CSD) is often utilized in head and neck surgical procedures to obliterate dead space. CSDs reduce seroma and hematoma formation, thereby improving skin apposition and wound healing. The use of drains for prolonged periods of time, however, may increase the risk of wound infection. Interestingly, the evidence regarding the need for, and management of, post-operative CSDs after head and neck surgery is scarce. The current criterion of drain removal when output is less than 30 cubic centimeters (cm3) within a 24-hour period and/or on the third post-operative day (POD) is widely utilized. The aforementioned criterion is based on anecdotal evidence from small studies with specific surgical procedures. In this study, we aim to evaluate the criteria for drain removal and to lay the groundwork for an updated paradigm for drain management in head and neck oncologic surgery.Study Design: Retrospective cohort studySetting: Academic tertiary care hospitalMethods: A retrospective study was performed. Patients were included if they underwent head and neck surgery at the University of Miami Hospital between January 1, 2019 and July 1, 2020 and had at least one CSD. Volume of drain output on each POD was recorded until the day of drain removal. The development of post-operative wound complications (i.e., seroma, hematoma, infection/abscess, and dehiscence) was also recorded.Results: From our initial cohort of 302 patients, 145 patients met inclusion criteria. A total of 10 patients developed a post-operative wound complication. Patients had a mean age of 58.3 ± 15.0 years. The median inter-quartile range (IQR) drain output (cm3) on the day of CSD removal from patients who developed a wound complication was similar (15; IQR, 5-37.5) when compared to those who did not develop a wound complication (25; IQR, 10-30). This difference was not statistically significant (p = 0.60). Additionally, the cohort who developed a post-operative wound complication had their drain removed on an earlier POD (1; IQR, 1-1 (Mean 1.2)) when compared to the cohort who did not develop any complications (1; IQR, 1-1 (Mean 1.5)). This difference was also not statistically significant (p = 0.48) .Conclusion: There is no association between drain output (cm3) or day of CSD removal with the development of wound complications. These results warrant further studies to prospectively evaluate earlier CSD removal in head and neck surgery.

A Perioperative Paradigm of Cranioplasty With Polyetheretherketone: Comprehensive Management for Preventing Postoperative Complications.

IntroductionAt present, lots of studies have discussed the effects and outcomes of cranioplasty using polyetheretherketone (PEEK). However, interventions or management for PEEK cranioplasty got less attention. This article presented a perioperative paradigm for preventing postoperative complications.Materials and MethodsModified PEEK plates with certified safety were implanted in patients who received evolving perioperative paradigm. Serial perioperative managements were developed as a comprehensive paradigm to prevent correlated risk factors of postoperative complications, which mainly included managements of epidural collections and wound healing. The preparation of the surgical area and systemic state were essential before surgery. During the operation, the blood supply of the incision and the handling of dura and temporalis were highlighted in our paradigm. After cranioplasty, management of subcutaneous drainage and wound healing were stressed. Patients received conventional management from February 2017 to August 2018 in our center. After the evolving paradigm developed, patients received comprehensive perioperative management from September 2018 to August 2020.ResultsA total of 104 patients who underwent PEEK cranioplasty were consecutively enrolled; 38 (36.5%) received conventional perioperative management, and 66 (63.5%) received evolving perioperative paradigm. The general information of the two groups was comparable. Notably, patients who received the evolving paradigm presented a significantly decreased incidence of postoperative complications from 47.4 to 18.2% (P < 0.01), among which the incidences of subcutaneous effusion, epidural hematoma, and subcutaneous infection decreased significantly.ConclusionThe evolving perioperative paradigm could effectively prevent risk factors and reduce related complications. It was valuable to promote these comprehensive managements and inspire more clinical practice on improving patients' outcomes after PEEK cranioplasty.

Assessing the incidence of complications and malignancies in the long-term management of benign biliary strictures with a percutaneous transhepatic drain.

Percutaneous drainage catheters (PDCs) are required for the management of benign biliary strictures refractory to first-line endoscopic treatment. While biliary patency after PDC placement exceeds 75%, long-term catheterization is occasionally necessary. In this article, we assess the outcomes of patients at our institution who required long-term PDC placement.A single-institution retrospective analysis was performed on patients who required a PDC for 10 years or longer for the management of a benign biliary stricture. The primary outcome was uncomplicated drain management without infection or complication. Drain replacement was performed every 4 to 12 weeks as an outpatient procedure.Nine patients (three males and six females; age range of 48–96 years) required a long-term PDC; eight patients required the long-term PDC for an anastomotic stricture and one for iatrogenic bile duct stenosis. A long-term PDC was required for residual stenosis or patient refusal. Drain placement ranged from 157 to 408 months. In seven patients, intrahepatic stones developed, while in one patient each, intrahepatic cholangiocarcinoma or hepatocellular carcinoma occurred.Long-term PDC has a high rate of complications; therefore, to avoid the need for using long-term placement, careful observation or early surgical interventions are required.

Development and application of DRAINMOD model for simulating crop yield and water conservation benefits of drainage water recycling

Drainage water recycling (DWR) is an emerging practice that has the potential to increase crop yield and improve water quality. DWR involves capturing and storing subsurface drainage water and surface runoff in ponds or reservoirs, and using this water for supplemental irrigation during dry periods of the growing season. The main objective of this study was to enhance DRAINMOD model to simulate the hydrology and crop yield of DWR systems. The expanded model; named DRAINMOD-DWR, has a new module that conducts a water balance of the storage reservoir and simulates the interaction between the reservoir and the field, irrigated from and/or draining into the reservoir. The model predicts the long-term performance of DWR as affected by weather conditions, soil type, crop rotation, reservoir size, and irrigation and drainage management. Three performance metrics were defined based on model predictions to quantify irrigation, crop yield, and water capture benefits of DWR. To demonstrate the new features of the model, uncalibrated DRAINMOD-DWR was applied to a hypothetical DWR system with continuous corn using a 50-yr (1970–2019) weather record in Eastern North Carolina, U.S. Different reservoir sizes were simulated to demonstrate how the model can predict the effect of storage capacity on the system’s performance. The model predicted that a 3.0-m deep reservoir with a surface area of 4% of the field area would optimize corn yield for the simulated conditions. The model application clearly demonstrated the DRAINMOD-DWR model’s capability of optimizing the DWR system design to avoid under-sizing or over-sizing the storage reservoir, which reduces system’s performance and increases implementation cost. Research is needed to test DRAINMOD-DWR using field measured data, and to develop routines for simulating the fate and transport of nutrients and sediment in the storage reservoir, which would enable the model to predict the water quality benefits of DWR.

Evaluation of gravity‐led and energy‐fed drainage for sustaining food security in the polders of the coastal zone of Bangladesh

AbstractBangladesh is currently self‐sufficient in rice production but faces immense challenges of sustaining that self‐sufficiency because of population growth and climate change. There is little scope to further increase cropping intensity except in the underutilized 1.2 Mha of lands enclosed in the polders of the coastal zone. The main impediment to wide‐scale adoption of more productive cropping systems in the polders is poor drainage that often results in waterlogging. Therefore, a study was conducted in polder 30, in the medium‐salinity region of the south‐west coastal zone, to examine the biophysical and economic feasibility of low‐cost gravity (gravity‐led) drainage. The results show a considerable opportunity to increase rice production in the polders with improved drainage practices. The feasibility of drainage through pumping (energy‐fed) was also assessed, given that there are already situations where gravity‐led drainage is not feasible, and these situations are likely to increase because of climate change‐induced sea level rise and the sinking of polder lands. Energy‐fed drainage was demonstrated to be profitable with a yield gain of at least 1.5 t/ha from just the wet season; further intensification to 50% of polder lands may yield an additional harvest of 3–6 million tons of rice per year. Therefore, investing in improved drainage management in the polders could be a major game changer in sustaining the food security of the nation, especially the climate‐vulnerable polder communities of Bangladesh.

Endoscopic drainage versus percutaneous drainage for the management of infected walled-off necrosis: a comparative analysis

ABSTRACT Background Comparative data on percutaneous catheter drainage (PCD) vs EUS-guided drainage (EUS-D) for management of symptomatic walled-off-necrosis (WON), specially infected WON with/without organ failure(OF) is limited. Methods Patients with symptomatic WON were divided into two groups of PCD and EUS-D, depending on the modality of drainage. Resolution of OF, adverse events, and other outcome measures were recorded. The two modalities were compared among infected WON sub-cohort and also degree of solid component (SC). Results 218 patients (175 males; 80.3%) were included who underwent either PCD (n = 102) or EUS-D (n = 116). Clinical success was significantly higher in the EUS-D group (92.1% vs 64.6%; p < 0.0001) and even for infected WON (n = 128) (p = 0.004), with higher (p = 0.007) and faster (p < 0.0001) OF resolution. Other outcome measures including mortality were significantly higher in the PCD group. Among subgroups, PCD with >40% SC had the worst clinical success/OF resolution rates, while EUS-D with <40% SC had the best outcomes. Conclusion EUS-D should be preferred over PCD in the management of WON, infected or otherwise, for higher clinical success, and higher/faster resolution of OF. PCD should be avoided in WON with>40% SC.

Management of Chest Drains after Elective, Thoracoscopic, Anatomical Lung Resections. A Survey in Thoracic Surgical Departments in Germany

The increasing use of minimally invasive techniques along with the introduction of the "Enhanced Recovery After Surgery" (ERAS) guidelines have reduced the perioperative risk of anatomic lung resections. However, the prolonged postoperative air leak still remains one of the major postoperative issues. The purpose of this survey was to evaluate the perioperative management of chest drains and the current clinical practice in treating prolonged air leaks after elective, thoracoscopic, anatomic lung resections in Germany. We performed a survey among the thoracic surgical units, which are listed in the Database of the German Thoracic Society (n=160). Based on the number of resections annually, the centres were divided into high- and low-volume and the results were presented accordingly. The response rate was 35.6%. Most of the units routinely place a single, 24 Ch. chest drain, which they connect to a digital system on suction. 42.1% of the thoracic units treat a postoperative air leak after the 7th postoperative day. The majority of the surgeons either reduce the suction or use other conservative measures to deal with the air leak. There is no significant difference in the drain management between high- and low-volume centres. The postoperative hospital stay after an uncomplicated lobectomy has come down to a few days whereas the lower limit of the length of stay has been reduced to 2 days. Nevertheless, 80% of the German thoracic surgeons define a postoperative air leak as prolonged, when it lasts beyond the 5th postoperative day and 65% deal with it only after the 5th postoperative day. The available evidence on this field is limited. New prospective clinical studies are required in order to improve the management of this common complication.

Absence of abdominal drainage after surgery for secondary lower gastrointestinal tract peritonitis is a valid strategy

Management of abdominal drainage after surgery for secondary lower gastrointestinal tract peritonitis (LGTP) is not a standardized procedure. A monocentric study was carried out in 2016 in our centre. (PI study) to evaluate the interest of drainage. Our objective was to revaluate, our actual use of abdominal drainage after peritonitis (PII study). We examined retrospectively patients who underwent surgery for secondary sub-mesocolic community-acquired peritonitis (January 2016-December 2019). Study exclusion criteria were primary peritonitis, peritoneal dialysis, nosocomial peritonitis, postoperative peritonitis, upper gastrointestinal tract peritonitis, peritonitis due to appendicitis, peritonitis requiring the implementation of Mikulicz's drain, and peritonitis in which the peritoneum was not described in the surgical report (i.e., the same criteria that the PI study which included 141 patients from January 2009 to January 2012). The primary endpoint was the rate of abdominal drainage. The secondary endpoints were the patient rate without a peritoneum description, major complications rate (Clavien ≥III), abscess rate, mortality rate and the length of stay in the non-drain group (D - ) and in the drain group (D + ) in PII study. Primary and secondary endpoints were also compared between PI and PII studies. Risk factors for post-operative abscess were also research. Of the 150 patients included 33% were drained vs 84% of the 141 patients included in PI study (p &lt; 0.001). In PII study peritoneum was described in 80.3% of patients vs 69% in PI study (NS, p = 0.06). Comparing the two groups D - and D + , no significant differences were found in major complications (respectively 45% vs 32%, p = 0.1), reoperation rate (respectively 25% vs 22%, p = 0.7), death rate (respectively 25% vs 14%; p = 0.1) and mean length of stay (respectively 12days vs 13days, p = 0.9). The abscess rate was significantly lower in the D - group (10% vs 30%, p = 0.002). Comparing PI and PII studies, there was no difference about major complications (35% vs 35%, p = 0.1), reoperation (16% vs 17.5%, p = 0.5), abscess rate (15% vs 8.5%, p = 0.1) and mortality (14.5% vs 17.5%, p = 0.7). The length of stay was longer in PI study than in P II (14days vs 9days, p = 0.03). Drainage (p = 0.005; OR = 4.357; CI [1.559-12.173]) and peritonitis type (p = 0.032; OR = 3.264; CI [1.106-9.630]) were abscess risk factors. This study therefore showed that drainage after surgery for LGTP may not be necessary and that, at least at the local level, surgeons seem to be inclined to discontinue it systematically. It may therefore be worthwhile to conduct a randomised control trial to establish recommendations on drainage after surgery for LGTP.

Novel approach for the management of acid mine drainage (AMD) for the recovery of heavy metals along with lipid production by Chlorella vulgaris

The treatment of acid mine drainage (AMD) is of paramount importance for environmental sustainability. A two-stage process involving AMD remediation and simultaneous lipid production represents a highly efficient approach with zero-waste generation. Alkaline (NaOH) treatment of AMD at pH 8.0, 10.0, and 12.0 had significantly reduced metal loads (copper (Cu), cobalt (Co), chromium (Cr), cadmium (Cd), nickel (Ni), and zinc (Zn)) compared to the acidic pH range (4.0 and 6.0). The concentration levels of sulfates (SO4 = 4520 mg/L), iron (Fe = 788 mg/L), aluminum (Al = 310 mg/L), and manganese (Mn = 19.4) were reduced to 2971 mg/L, 10.3 mg/L, 16.4 mg/L, and 1.3 mg/L, respectively at pH value 8.0. AMD with a pH value of 8.0 was later chosen as an ideal medium to favor the lipid accumulation by Chlorella vulgaris. Algal biomass was increasing to 5.5 g/L from 0.6 g/L of AMD-based medium within 15 days of cultivation. The FTIR and SEM-EDS studies revealed significant morphological changes in the microbial cell wall. The metals might positively impact lipid production in microalgae, where lipid yield achieved 0.18 g/g of glucose with lipid content of 0.35 g/g of biomass. The fatty acid profile presented 53.4% of saturated fatty acid content with a cetane value of 60.7. Thus, the efficiency of C. vulgaris was demonstrated with AMD treatment proving it to be a good candidate for bioenergy production.

Abstract WP109: Association Of Cisternal Blood Clot Burden And Ventriculoperitoneal Shunt Requirement In Subarachnoid Hemorrhage

Background: Aneurysmal Subarachnoid hemorrhage (aSAH) can be complicated by refractory hydrocephalus requiring a ventriculoperitoneal shunt (VPS). In an effort to optimize external ventricular drain (EVD) management, we sought to identify early radiographic predictors for refractory hydrocephalus requiring VPS placement. Methods: We conducted a retrospective case-control study of patients admitted for aSAH to a referral academic center from 2016 to 2021. We included those who survived their hospital course and compared radiographic features on admission non-contrast head CTs of patients who required a VPS and those who did not. We calculated modified GRAEB scores and measured total blood clot thickness (blood clot cisternal score) in the basal cisterns including interpeduncular, ambient, crural, prepontine, suprasellar, and interhemispheric cisterns plus bilateral Sylvian fissures (in mm). Binary logistic regression was used to test the association of VPS requirement with radiographic features. Receiver operating characteristics (ROC) curve analysis was performed to compare predictive accuracy of cisternal score to other predictors. Results: Our inclusion criteria yielded 176 patients (mean age of 54.9 years [SD 12.8]; 57% female, 70% white) of which 29 (16.5%) required a VPS. Cisternal score was greater in patients who required a VPS than those who did not (median 61.6 mm, IQR 49.8-74.3 mm vs 26.8mm, IQR 12.4-46.7; p&lt;0.001). Binary logistic regression showed higher blood clot cisternal score on admission head CT scan was associated with higher odds of developing refractory hydrocephalus with VPS requirement (odds ratio 1.06 per each millimeter increase, 95% CI 1.03-1.09; p&lt;0.001), independent of age, Hunt and Hess grades and modified GRAEB scores. Blood clot cisternal score has higher accuracy in predicting VPS requirement than modified GRAEB score (AUC 0.83, 95% CI 0.74-0.93 vs AUC 0.72, 95% CI 0.63-0.82) and other clinical or radiographic predictors on admission. Conclusions: While further validation is needed, our model suggests that blood clot cisternal score on admission head CT scan has high accuracy in predicting VPS requirement. This may allow for more efficacious and cost-effective treatment of hydrocephalus in aSAH patients.

Management of agricultural saline drainage using system dynamics approach

AbstractAgricultural drainage water quality changes over time until it reaches a balance. In areas with shallow and saline groundwater, it might take several years to reach a balance. In such cases, knowledge of the quantity and quality of drainage water is necessary to manage it. The drainage water generated must then be managed for reuse purposes where it is of suitable quality and is finally discharged or disposed of. In this paper, the system dynamics technique was used to manage this drainage water. The study used the system dynamic programming tool VENSIM. The model developed in this study is capable of managing drainage water by combination of existing solutions such as mixture of irrigation water, used for downstream and cultivation of salt tolerant plants, used for irrigation of salt‐friendly plant, discharged into a river and discharged to evaporation ponds, simultaneously. The model was run using actual data for Khuzestan Province of Iran. The results showed that the model could be an opportunity for the design and management of drainage systems.

Early biochemical predictors of clinically relevant pancreatic fistula after distal pancreatectomy: a role for serum amylase and C-reactive protein.

Recent evidence suggests that pancreatic inflammation plays a pivotal role in the occurrence of clinically relevant postoperative pancreatic fistula (CR-POPF) after pancreaticoduodenectomy but few data are available for distal pancreatectomy (DP). The aim of this study was to evaluate the impact of early biochemical markers on the occurrence of CR-POPF after DP. Clinical and laboratory data for 432 consecutive DP patients were reviewed. Serum amylase was evaluated on postoperative day (POD) 1, and drain fluid amylase (DFA) and C-reactive protein (CRP) were evaluated on POD 2 and 3. Receiver operator characteristic (ROC) curves were performed for all biochemical markers and an area under the curve (AUC) was computed. Multivariable regression analyses to identify the factors associated with CR-POPF and severe postoperative morbidity (Clavien-Dindo grade ≥ 3) were performed. At 90 days after surgery, CR-POPF occurred in 155 (36%) patients, severe complications in 66 (15%) patients. ROC curve analyses showed that DFA on POD2 had the largest AUC (0.753, p < 0.001), followed by serum amylase on POD 1 (0.651, p < 0.001), serum CRP on POD3 (0.644, p < 0.001), and CRP change between POD 2 and POD 3 (0.644, p < 0.001). Multivariable analysis identified male gender (OR 2.29, 95% CI 1.36-3.86; p = 0.002), DFA ≥ 1500 U/Lon POD2 (OR 4.63, 95% CI 2.72-7.89; p < 0.001), serum amylase ≥ 100 U/L on POD 1 (OR 1.72, 95% CI 1.01-2.93; p = 0.046), and CRP increase by at least 25mg/L on POD 3 compared to the previous day (OR 1.89, 95% CI 1.11-3.21; p = 0.019) as independent predictors of CR-POPF, yielding a valid regression model (AUC 0.765, 95% CI 0.714-0.816, p < 0.001). Postoperative serum amylase and CRP trajectory represent useful early biochemical markers for CR-POPF in addition to DFA. Our findings suggest that these laboratory tests should be incorporated into clinical practice to aid postoperative patient and drain management.