Flush Device Research Articles

Evaluation of the Environmental and Economic Impacts on the Life Cycle of Different Solutions for Toilet Flush Systems

The use of plumbing fixtures to promote water saving in the built environment is a common practice in water conservation programs. However, the environmental implications of fixtures replacement should be taken into consideration. This paper analyzes three different scenarios for the provision of water in toilets installed in a university campus. In scenarios 1 and 2, single flush and dual flush devices were installed in the toilets, respectively. In scenario 3, in addition to the installation of dual flush devices, a greywater reuse system from the lavatories was analyzed. The objective is to evaluate, through the Life Cycle Assessment, the environmental aspects related to these scenarios. The economic analysis of the three scenarios was also carried out. Measurements were taken on all plumbing fixtures installed in a building of a university campus in Southern Brazil. The research was conducted using smart meters in two periods: with single flush and dual flush devices installed in toilets. Considering the environmental impacts analyzed, scenario 3 presented lower water and energy consumption in the life cycle. Scenario 2, however, presented lower global warming potential. The net present value results were R$ 23,575.71, R$ 19,091.41, and R$ 22,500.55 for scenarios 1, 2 and 3, respectively.

Analysis of water consumption in toilets employing Shewhart, EWMA, and Shewhart-EWMA combined control charts

The objective of this article is to statistically analyze and apply process control on water consumption in toilet flush devices in a public university building using Shewhart, EWMA and combined Shewhart-EWMA control charts. Data such as water volume, number of activations and flush-time duration were collected utilizing Smart-Meter sensors. A script was developed in R language to perform the appropriate statistical analysis, such as finding control charts control limits and transforming the obtained raw data into key variables: total volume per day, average flush volume, flush duration, and number of flushes per day. During the data gathering period, the regular single-flush equipment was replaced by a dual-flush model. The control charts Phase 1 is based on the collected data before the installation of the dual-flush devices, while Phase 2 is based on after replacement. After installing the new dual-flush devices, all control charts displayed visible changes based on the key variables. The replacement of the flush valves brought about a considerable reduction in water consumption in both male and female restrooms. There was a 21.72% reduction in average water consumption and a 12.09% average reduction in flushing time duration. The equipment replacement resulted in an evaluated Internal Rate of Return of 0.73%. Periodic monitoring of Shewhart Control Charts proved useful for observing large shifts of data, while EWMA control charts were more useful in locating small but constant data shifts. All chart models proved useful in identifying water consumption reduction and events such as leakages and water supply cutoffs occurring during the data gathering period.

Comportamento de dispositivos de desvio das primeiras águas de chuva como barreiras sanitárias para proteção de cisternas

O uso de cisternas para armazenamento da água de chuva é comum em diversas localidades que experimentam longos períodos de escassez hídrica. Para evitar a contaminação da água armazenada, uma das estratégias é o uso de dispositivos de descarte das primeiras águas de chuva. Neste estudo foi analisada a qualidade da água (parâmetros físico-químicos e microrganismos patogênicos) desviada do sistema de armazenamento, com o emprego de três tipos de dispositivos de descarte automático: um baseado no princípio de fecho hídrico (chamado aqui de Dispositivo A1 – ANDRADE NETO, 2004), um baseado no princípio dos vasos comunicantes (chamado aqui de Dispositivo A2 – www.cepfs.org) e um baseado em ambos os princípios físicos (chamado aqui de DesviUFPE - ALVES et al., 2014). Ambos os desvios Dispositivo A1 e Dispositivo A2 são confeccionados em concreto e o DesviUFPE em tubos de PVC acoplados. Além disso, foi investigada a qualidade da água armazenada nas cisternas para comparação dos resultados com os padrões de potabilidade estabelecidos pela legislação. Todos os desvios considerados constituem o ponto de passagem obrigatório entre a calha acoplada no telhado e a cisterna. Todos os dispositivos de desvio estudados resultaram em melhoria na qualidade da água armazenada, ressaltando-se os resultados obtidos para cor real e aparente, turbidez, sólidos totais, coliformes total e E. Coli. Observou-se que exceto para cor aparente, turbidez, pH e OD, os demais parâmetros de qualidade analisados na água da cisterna sem desvio foram numericamente maiores aos obtidos para as outras cisternas, evidenciando a necessidade do emprego do desvio.

Percutaneous Transtracheal Jet Ventilation with Various Upper Airway Obstruction.

A “cannot-ventilate, cannot-intubate” situation is critical. In difficult airway management, transtracheal jet ventilation (TTJV) has been recommended as an invasive procedure, but specialized equipment is required. However, the influence of upper airway resistance (UAR) during TTJV has not been clarified. The aim of this study was to compare TTJV using a manual jet ventilator (MJV) and the oxygen flush device of the anesthetic machine (AM). We made a model lung offering variable UAR by adjustment of tracheal tube size that can ventilate through a 14-G cannula. We measured side flow due to the Venturi effect during TTJV, inspired tidal volume (TVi), and expiratory time under various inspiratory times. No Venturi effect was detected during TTJV with either device. With the MJV, TVi tended to increase in proportion to UAR. With AM, significant variations in TVi was not detected with changes in any UAR. In conclusion, UAR influenced forward flow of TTJV in the model lung. The influence of choked flow from the Venturi effect was minimal under all UAR settings with the MJV, but the AM could not deliver sufficient flow.

Low Cost Rainwater Harvesting: An Alternate Solution to Salinity Affected Coastal Region of Bangladesh

This study investigated the prospect of rainwater harvesting as a low cost alternative potable water supply option along the coastal region of Bangladesh, which is considered as one of the most vulnerable countries in the world due to climate change and resulting sea level rise. Because of increasing salinity intrusion, potable water scarcity become severe at the south-western coastal region of the country. The study area for this investigation was Patkelghata in Satkhira district of Bangladesh located in the same zone. The Satkhira district averages nearly 1,710 mm rainfall per year. Based on rural housing pattern of the region, a rainwater harvesting system is proposed, which consists of roof catchment, gutters, down pipes, first flush devices, filter chamber and storage tank. The minimum catchment area was assumed to be 6 m2 and storage tank of 2000 liter capacity. Data was collected on the present state of freshwater supply, sources and quality, average rainfall in the region, dry spell period, family size, water use nature, rain water quality and material to be used for storage, etc. Rainwater quality was also tested and the parameters were found to be within Bangladesh’s standard limit. After a detail calculation, an approximate cost was assumed to be $171 for building and operation of the whole system. A questionnaire survey was also conducted on views and opinion of local people to understand the problems, prospects and the popularity of rainwater harvesting in Bangladesh.

Quality and Quantity Monitoring of Five Rainwater Tanks in Western Sydney, Australia

AbstractRainwater tanks are a fundamental component of integrated water cycle management, but the quality of harvested water is little understood and is potentially affected by many factors such as roofing material, site temperature, frequency of tank use, and surrounding land use. There has been limited study of the first flush, overflow water and harvested water quality from rainwater tanks in Australia. This paper presents the water quality results of a yearlong data collection and analysis study involving five rainwater tanks located in Western Sydney, Australia. The results show that tank water quality was impacted by the construction materials used to fabricate both the tanks and roofs. Furthermore, the overflow and first flush water quality were found to be of a lower standard than the tank samples, with implications for the cleaning of the first flush device and overflow diversion. Finally, the issues identified with the maintenance of the tanks are highlighted and discussed.

Risk in the mist? Deriving data to quantify microbial health risks associated with aerosol generation by water-efficient devices during typical domestic water-using activities

The aim of this study was to address existing data gaps and to determine the size distribution of aerosols associated with water-efficient devices during typical domestic activities. This information is important to assist in understanding infection spread during water-using activities and in designing water regulations. Three water-using scenarios were evaluated: i) showering using a water-efficient showerhead; ii) use of a high pressure spray unit for cleaning cars and iii) toilet flushing using a dual flush low volume flush device. For each scenario a control condition (conventional lower efficiency device) was selected for benchmarking purposes. Shower module results highlighted the complexity of particle generation and removal processes and showed that more than 90% of total particle mass in the breathing zone was attributed to particle diameters greater than 6 mum. Conversely, results for car washing experiments showed that particle diameters up to 6 mum constituted the major part of the total mass generated by both water-efficient and conventional devices. Even under worse case scenario conditions for toilet flushing, particle measurements were at or below the level of detection of the measuring instrumentation. The data provide information that assists in health risk assessment and in determining future research directions, including methodological aspects.

Tibiofemoral contact mechanics with a femoral resurfacing prosthesis and a non-functional meniscus

Background Increased contact stress with a femoral resurfacing prosthesis implanted in the medial femoral condyle and a non-functional meniscus is of concern for potential deleterious effects on tibiofemoral contact mechanics. Methods Peak contact pressures were determined in seven fresh frozen human cadaveric specimens using a pressure sensitive sensor placed in the medial compartment above the menisci. A knee simulator was used to test each knee in static stance positions (5°/15°/30°/45°) and through 10 dynamic knee flexion cycles (5–45°) with single body weight ground reaction force which was adjusted to the living body weight of the cadaver donor. All specimens were tested in three different conditions: untreated knee (A); flush implantation of a 20 mm resurfacing prosthesis (HemiCAP ®) in the weight bearing area of the medial femoral condyle (B); complete radial tear at the posterior horn of the medial meniscus with the femoral resurfacing device in place (C). Findings On average, flush device implantation resulted in no statistically significant differences when compared to the untreated normal knee. The meniscal tear resulted in a significant increase of the mean maximum peak contact pressures by 63%, 57%, and 57% (all P ⩽ 0.05) at 15°, 30° and 45° static stance positions and 78% ( P ⩽ 0.05) through the dynamic knee flexion cycle. No significant different maximum peak contact pressures were observed at 5° stance position. Interpretation Although the condition of a meniscal tear without the resurfacing device could not be compared, possible effects of reduced meniscal tissue and biomechanical integrity of the meniscus must be considered in an in vivo application.

Mini-epidemic of Erroneous Central Venous Pressure Measurements Resulting from the Malproduction of a Specific Part of a Pressure Transducer System

Global Product Manager Invasive Blood Pressure Monitoring and Interventional Imaging, Smiths Medical International Ltd., Military Road, Hythe, United Kingdom. helen.reeve@smiths-medical.comWe would like to make the following comments in response to the article by Dr. Görlinger et al. (Görlinger K, Kehren CJ, Peters J: Mini-epidemic of erroneous central venous pressure measurements due to malproduction of a specific part of a pressure transducer system. Anesthesiology 2009; 110:1417–8).In 2008, Smiths Medical became aware of a manufacturing fault with its pressure monitoring kits; this fault has since been rectified. The products involved were LogiCal®, NovaTrans®, and TranStar® invasive pressure monitoring kits with trigger flush device, product codes DPSxxxxxx/MX95xxxx/MX96xxxx/MXxxx and SXxxxxxx and manufactured between October 2007 and February 2008. In the affected kits, flow rates were higher than the product specification of 3 ml/h due to communication between the slow-flow orifice and the flush. The cause of the fault was identified as an assembly problem, and corrective actions were implemented to prevent reoccurrence.Customers who had purchased sets manufactured within the specified timeframe were notified of the problem via a field safety notice, and regulatory bodies were informed.Customers were advised to perform a precheck during priming of each device and before connecting to the patient to identify whether the issue was present. Separate instructions to assess kits already in use were also provided. Customers with affected kits were advised to contact their sales representative for free collection and replacement.The following procedure is recommended for testing the flow rates of these kits:Pretest:Devices already in use with patients can be checked by observing the flow rate in the drip chamber as described above. When the flush is not being operated, the flow rate observed in the drip chamber should be:If the flow rate in the drip chamber is greater than this, it should be discarded and replaced with a new device that has passed the pretest.Smiths Medical takes the quality of its products and the satisfaction of its customers very seriously. If a product fails to meet expectations, they should not hesitate to contact us. We investigate all complaints thoroughly and undertake any necessary corrective actions.Global Product Manager Invasive Blood Pressure Monitoring and Interventional Imaging, Smiths Medical International Ltd., Military Road, Hythe, United Kingdom. helen.reeve@smiths-medical.com

Effects of a contoured articular prosthetic device on tibiofemoral peak contact pressure: a biomechanical study

Many middle-aged patients are affected by localized cartilage defects that are neither appropriate for primary, nor repeat biological repair methods, nor for conventional arthroplasty. This in vitro study aims to determine the peak contact pressure in the tibiofemoral joint with a partial femoral resurfacing device (HemiCAP®, Arthrosurface Inc., Franklin, MA, USA). Peak contact pressure was determined in eight fresh-frozen cadaveric specimens using a Tekscan sensor placed in the medial compartment above the menisci. A closed loop robotic knee simulator was used to test each knee in static stance positions (5°/15°/30°/45°) with body weight ground reaction force (GRF), 30° flexion with twice the body weight (2tBW) GRF and dynamic knee-bending cycles with body weight GRF. The ground reaction force was adjusted to the living body weight of the cadaver donor and maintained throughout all cycles. Each specimen was tested under four different conditions: Untreated, flush HemiCAP® implantation, 1-mm proud implantation and 20-mm defect. A paired sampled t test to compare means (significance, P ≤ 0.05) was used for statistical analysis. On average, no statistically significant differences were found in any testing condition comparing the normal knee with flush device implantation. With the 1-mm proud implant, statistically significant increase of peak contact pressures of 217% (5° stance), 99% (dynamic knee bending) and 90% (30° stance with 2tBW) compared to the untreated condition was seen. No significant increase of peak contact pressure was evaluated with the 20-mm defect. The data suggests that resurfacing with the HemiCAP® does not lead to increased peak contact pressure with flush implantation. However, elevated implantation results in increased peak contact pressure and might be biomechanically disadvantageous in an in vivo application.

Randomized Evaluation of the TriActiv Balloon-Protection Flush and Extraction System for the Treatment of Saphenous Vein Graft Disease

The Protection During Saphenous Vein Graft Intervention to Prevent Distal Embolization (PRIDE) study compared outcomes with the TriActiv System (Kensey Nash Corp., Exton, Pennsylvania), a balloon-protection flush and extraction device, with an embolic protection group during treatment of saphenous venous grafts (SVGs). Treatment of SVGs with embolic protection reduces adverse cardiac events. We conducted a prospective trial randomizing 631 patients with coronary ischemia and lesions in SVGs to embolic protection with the TriActiv System or control group (Guardwire System [Medtronic AVE, Santa Rosa, California] or Filterwire EX [Boston Scientific Corp., Maple Grove, Minnesota]). The incidence of major adverse cardiac events at 30 days was 11.2% for the TriActiv group and 10.1% for the control group (relative risk = 1.1%; 95% confidence interval 0.67 to 1.76; p = 0.65; p = 0.02 for non-inferiority). Safety and efficacy end points were similar between groups except that patients randomized to the TriActiv System had more hemorrhagic complications (10.9% vs. 5.4%; p = 0.01). The TriActiv System was not inferior to approved embolic protection devices for the treatment of diseased SVGs.

The effect of hypotensive anaesthesia on cognitive functions and recovery at endoscopic sinus surgery

The effect of hypotensive anaesthesia on cognitive functions and recovery at endoscopic sinus surgery

Outbreak of Multiantimicrobial-Resistant Acinetobacter baumannii Related to Pulsatile Lavage

ISSUE: We investigated an outbreak of multiantimicrobial-resistant Acinetobacter baumannii (MDR-AB) in a 1000-bed hospital. A. baumannii survives on surfaces for extended time periods and colonizes or infects the respiratory tract and wounds. PROJECT: In October 2003, 12 patients had MDR-AB cultured from wounds. Cases were patients with cultures (CX) growing MDR-AB. MDR-AB were resistant to all antibiotics except colistin. Strict contact isolation was implemented. Sign-in was required for entry into patient pt rooms to track potential exposures. Record review revealed that all case patients underwent wound care with Pulsatile Lavage (PL), which is a pressurized wound flush device. The procedure was observed, environmental CX were collected in the treatment area and all patients who underwent PL were identified. CX of the PL environment grew MDR-AB. The treatment area was closed and thoroughly cleaned. Staff was instructed on proper infection control. Surveillance CX of all patients treated with PL was obtained from the time the index case was identified. Pulsed-field gel electrophoresis revealed that 6 patients who received PL had identical strains, which were also identical to environmental CX. We hypothesized the organism was aerosolized during PL therapy based on 1) environmental contamination matching the outbreak strain, and 2) infected patients. RESULTS: The outbreak resolved after all CX-positive patients were identified and aggressive infection control measures were instituted. No new cases were identified after October 2003. LESSONS LEARNED: MDR-AB can be transmitted by aerosolization during PL. The FDA and CDC have worked to change the infection control procedures in the product labeling on the PL device.

Capping Arterial Sheaths in Patients Undergoing Percutaneous Coronary Intervention: Evidence-Based Practice

medications, the care for these patients changed. Instead of being left in overnight, the arterial and venous sheaths were removed when the activated clotting time was less than 180 seconds (approximately 2-4 hours after the procedure), and the transducer and heparinized flush device were discarded. Although the time the sheaths remained in place after PCI changed, nursing practice remained the same. Connecting a transducer to the arterial sheath requires additional nursing time to set up the heparinized and pressurized flush device. In sharing information with nurses from other institutions and with nurses who had joined our staff, we found that using a transducer and monitoring the arterial sheath are not universal nursing practices. Little clinical research has been done on management of the vascular access sites after PCI. Juran

Emergency transtracheal ventilation: assessment of breathing systems chosen by anaesthetists.

The choice of equipment for emergency transtracheal ventilation and the time taken to assemble it were surveyed in 39 anaesthetists. Thirty seven (95%) assembled a system in a median time of 104 s (interquartile range 54 s to 120 s). Systems specially constructed from oxygen tubing and connectors took longest to put together (p < 0.05). Consultants and senior registrars performed no better than senior house officers and registrars (p > 0.05). In the second part of the study we tested four anaesthetic systems which the survey revealed might be chosen for emergency transtracheal ventilation. These were: a simple length of oxygen tubing; a T-piece system; a Bain system; a jet injector. All had the appropriate connectors. The oxygen flow was measured through a 14 G venous "transtracheal' cannula on depression of the oxygen flush device on a standard Boyle's M anaesthetic machine. The jet injector was connected to the high pressure outlet. This device delivered the highest flow, 43 l.min-1 and was the only system capable of ventilating a trachea/lung model. The T-piece system, and the one constructed from oxygen tubing, delivered flows of 12.7 and 12.0 l.min-1, respectively, whereas the Bain system delivered only 4.7 l.min-1. We conclude that, except for jet ventilation, none of the systems chosen, using equipment available in the anaesthetic room, would be likely to achieve effective CO2 elimination; at best they would provide oxygenation.

Cathétérisme artériel et mesure invasive de la pression artérielle en anesthésie-réanimation chez l'adulte

A group of 13 experts appointed by the French Society of Anaesthesia and Intensive Care has produced the following guidelines for arterial catheterisation and invasive measurement of systemic arterial blood pressure in adults. Teflon ® or polyurethane catheters are recommended with a maximal size of 18 gauge for femoral and axillary arteries and 20 gauge for the others. For small arteries (radial and pedious arteries) a maximal length of 3–5 cm should be preferred. The benefit of heparin-coating is not documented. Incorporation of salts for radiopacity is useless and increases thrombogenicity. Use of a flush device with a constant flow of 2 mL·h −1 and a fast flush valve connected to normal saline under pressure is recommended. Manual intermittent flushing with a syringe is contra-indicated. Addition of heparin (2500 IU·500 mL −1 of flush solution) increases the duration of catheter patency and is recommended for catheterisations of more than 24 h duration. Ready for use devices are to be preferred. Distortion of pressure wave may be minimized by employing low volume, low compliance, low resistance devices. The number of connections should be as low as possible and all of Luer-lock type. The stopcocks should be clearly indentified to minimize the risk of accidental intra-arterial injection. The device should be transparent for disclosure of bubbles, which lead to waveform distortion. For catheter placement the operator should follow the usual preparation as for any aseptic surgical procedure with cap, mask, gloves and sterile towel. The insertion site is prepped either with chlorhexidine or povidone-iodine. In the conscious patient, local anaesthesia by injection and/or topical application (EMLA ®) is recommended. Direct arterial puncture should be preferred rather than transfixion. Catheterisation of deep vessels is facilitated by Seldinger technique, which is recommended whatever the site of placement when long term monitoring and/or difficulties of insertion are foreseen. The radial artery is the site of choice for elective cases. The non-dominant hand should be preferred. Puncture must be preceded by assessment of adequacy of the collateral flow by the Allen test. The femoral artery is a valuable site for emergency situations. Before catheterisation, the artery should be auscultated for a murmur. Puncture of a vascular prosthesis is contra-indicated. The dressing should be changed every four days only. Sites of blood withdrawal should be manipulated with compresses soaked with chlorhexidine or povidone-iodine. The arterial catheter is only changed in case of evidence of local infection or ischaemia. The catheter removal should be considered as an aseptic surgical procedure. The catheter completeness has to be checked. A systematic culture of the catheter is not required.

Construction and use of catheter-manometer systems.

The accuracy of invasive arterial blood pressure monitoring is dependent on an adequate damped natural frequency (DNF) and damping factor (DF) of the system. Several factors influencing the DNF and DF were investigated to determine requirements for optimal design of catheter-manometer systems. The frequency sweep method was used in a specially constructed chamber that included linearizing and compensation circuitry. The DNF of isolated 20-gauge cannulae varied from 35.1 to 47.7 Hz. The DNF of 24-gauge cannulae varied from 27.7 to 44.3 Hz. An arterial cannula was found to require a DNF above 40 Hz to prevent the DNF from decreasing to below 25 Hz with the addition of arterial pressure tubing. Arterial pressure tubings exceeding 300 mm in length had DNF values that were unacceptably low even before the addition of arterial cannulae (e.g., the DNF was 23.8 Hz for a 900-mm tubing length, 19.8 Hz for 1,000-mm length, and ranged from 12.9 to 21.4 Hz for 1,200-mm lengths). The 3-way stopcocks and continuous flush devices further decreased the DNF, especially when the diameters were not matched. The percentage decrease caused by 3-way stopcocks and flush devices ranged between 19.5 and 40.8% for 300-mm length tubings and between 2.3 and 25.8% for tubings of 1,200-mm lengths. The radius ratio (outside diameter divided by inside diameter) is introduced as a new method to express the stiffness of arterial pressure tubing.(ABSTRACT TRUNCATED AT 250 WORDS)

The fast flush test measures the dynamic response of the entire blood pressure monitoring system.

The fast flush test (FT) is the only test that allows clinicians to determine in vivo the natural frequency (fn) and damping coefficient (zeta) of an invasive blood pressure monitoring system. The underlying assumption to the validity of the FT is that it activates the whole system including the distal catheter. We devised an in vitro model of a typical invasive blood pressure monitoring system to determine whether this assumption was true. The model consisted of a conventional transducer with a flush device attached to various lengths of connecting tubing (91.4, 182.9, and 274.3 cm) terminated by four different diameter catheters (5.1 cm 14 G, 16 G, 18 G, and 20 G). A microtipped transducer catheter was inserted into the distal catheter tubing system. A FT was performed and the fn and zeta were recorded from the conventional transducer and simultaneously from the microtipped transducer catheter. Similar studies were conducted using the ROSE damping device as well as with systems including 0.1 ml of air near the conventional transducer. These studies utilized 18- and 20-G catheters with each of the three lengths of connecting tubing. All measurements of fn and zeta at the proximal conventional transducer were identical to those measurements as recorded by the distal microtipped transducer catheter. We conclude that the FT activates the whole monitoring system and that fn and zeta are the same throughout the system including the distal catheter.

Failure of oxygen flush device

Failure of oxygen flush device

Availability of intraarterial pressure waveforms from catheter-manometer systems during surgery.

We determined how often and for how long usable pressure waveforms were unavailable from a radial intraarterial pressure cannula during anesthesia and surgery in 41 patients. During cardiac surgery with a continuous flush system, usable arterial pressure was unavailable 8.7% of the time. It was unavailable 9.1% of the time during noncardiac surgical procedures with a continuous flush system, and 14.7% of the time in system without continuous flush. Thus, the use of a continuous flush device improves intraarterial pressure availability. Artifact is the principal contributor to unavailability, followed by flushing and blood sampling. With rare exceptions the use of a Riva-Rocci cuff for occasional return-to-flow maneuvers on the same arm as the intraarterial cannula reduces intraarterial pressure availability only slightly, certainly not enough to detract from its usefulness in providing an estimation of systolic pressure during intraarterial pressure monitoring.