External Drainage System Research Articles

Investigation of risk factors for external ventricular drainage‑associated central nervous system infections in patients undergoing neurosurgery.

Meningitis/ventriculitis (MV) is an illness which can occur as a complication following neurosurgical procedures. Devices such as an external ventricular drain (EVD) are also related to considerable complications, such as infections. The present study examined the risk factors associated with central nervous system (CNS) infections associated with the external ventricle drainage system. The present retrospective study included all patients hospitalized between April, 2011 and August, 2018 who had been receiving therapy with EVD for developed hydrocephalus. A total of 48 out of 65 patients were classified into two groups as follows: Patients without MV (group A) and patients who developed MV (group B). The durations of hospital stay and intensive care unit (ICU) stay were significantly lower in group A (32.4±24 and 21.1±11 days, respectively) compared to group B (54.7±37 and 42±24 days, respectively) (P=0.027 and P=0.001, respectively). The Acute Physiological and Chronic Health Evaluation II (APACHE II) score and EVD distance from the wound exit side to the burr hole were significantly lower in the survivors compared to the non-survivors (17.5±6 and 15.4±4 vs. 22.5±6 and 39.8±38, respectively). Receiver operating characteristic analysis revealed that the APACHE II score with an area under the curve [(AUC) of 0.677, P=0.044, and 95% confidence interval (CI) of (0.516-0.839)] and a cut-off value of 14 could predict mortality with a sensitivity of 100% and a specificity of 71%; the EVD distance from the wound exit side from the burr hole with an AUC of 0.694 (P=0.028), 95% CI of 0.521-0.866 and a cut-off value of 11.5 mm could predict mortality with a sensitivity of 88% and a specificity of 83%. On the whole, the present study demonstrates that the EVD-related distance from the wound exit side of the burr hole can predict poor outcomes due to CNS infections in patients undergoing neurosurgery.

Oligocene–Miocene northward growth of the Tibetan Plateau: Insights from intermontane basins in the West Qinling Belt, NW China

Growth of the Tibetan Plateau, Earth’s broadest and highest elevation collisional system, shapes orographic barriers, reorganizes drainage networks, and influences surface erosion and sediment delivery, whose changes in space and provenance feed back to intracontinental tectonic processes. Studies of interior basins within the northern Tibetan Plateau provide new sediment accumulation, provenance, paleodrainage, and deformation timing data that enable a reconstruction of the far-field tectono-geomorphic evolution of the rising Tibetan Plateau. Along the northern plateau margin, topographic growth in the West Qinling Belt is inferred to have initiated in the Eocene, nearly coeval with the India-Asia collision, as well as in the late Miocene. However, geological knowledge about the intervening period remains at present enigmatic, and the kinematics and dynamics are uncertain. This study presents a multidisciplinary data set from the intermontane Anhua-Huicheng Basin (AHB; Gansu Province, China) to fill this gap. Magnetostratigraphic dating, regional mapping, and sedimentological analysis imply that contractional deformation and thrust-top basin systems formed within the West Qinling Belt in the Oligocene (not later than ca. 24 Ma). A combination of observations including paleocurrent changes, detrital zircon U-Pb age variations, and appearance of growth strata along the Anhua-Huicheng Basin reveal the rapid uplift of the West Qinling Belt at ca. 15 Ma. Sedimentation in the intermontane basins ended after the late Miocene (ca. 8 Ma), when the region experienced intrabasinal deformation, uplift, and erosion with the establishment of an external drainage system. Since the late Miocene, the growth of the West Qinling Belt reached a climax with the lack of substantial contractional deformation in Cenozoic sequences heralding the onset of the modern kinematic regime and attainment of high elevation. Observed transitions in the tectonostratigraphy and paleodrainage define different phases of deformation and plateau-wide shifts in stress reorganization, which led to the northward growth and later lateral expansion of the Tibetan Plateau.

Mathematical model of fluid flow along a straight through filled with a distributed flow from above

In a one-dimensional approximation and in the absence of friction forces, a mathematical model has been developed for the steady flow of an incompressible fluid along a straight line, for example, a drainage gutter, into which a distributed flow flows from above. The boundary condition missing for solving the system of equations of momentum and continuity is determined using the principle of minimum potential energy. For a rectangular chute, equations are obtained that allow one to calculate the distributions of the layer thickness and fluid velocity along the length of the chute with a plug at one end and without a plug, slope and without slope to the horizon, depending on the intensity of the incoming flow, the size of the chute, and the density of the liquid. This model, by means of a simple recalculation, can also be extended to the flow in a trough of a different cross-sectional profile. The results of the study can be applied to the calculation of external drainage systems.

Use of Centrifuge-Based Physical Modelling for Understanding the Performance of Geostructures

Centrifuge-based physical modelling is widely adopted for understanding the performance of geostructures, like levees subjected to flooding and drawdown and geogrid-reinforced soil walls subjected to seepage. In this paper, an attempt has been made to bring out the advantage of centrifuge-based physical modelling to understand (i) the performance of levees subjected to flooding using a custom-designed and developed in-flight flood simulator at 30 gravities with and without chimney drain and (ii) the performance of geogrid-reinforced soil walls with and without chimney drain subjected to seepage at 40 gravities. In both the cases, silty sand was used to model soil and fine sand was used in chimney drain. All centrifuge model tests were performed using the 4.5-m-radius large-beam centrifuge facility available at IIT Bombay. Models were instrumented with linearly variable differential transformers for measuring surface settlements and pore pressure transducers to measure raise in pore water pressure within the soil at the onset of flooding for levees and at the onset of seepage for geogrid-reinforced soil walls. Additionally, digital image analyses of photographs of front elevation of levee models and geogrid-reinforced soil wall models were carried out to obtain face movements, movements of markers embedded within the levee, markers stuck to geogrid layers of reinforced soil walls at the onset of flooding and seepage. The developed in-flight flood simulator was found to be capable of generating the flood rate ranging from 2.2 to 7 m/day. Further, results of centrifuge model tests conducted on levees without any chimney drain were noticed to undergo catastrophic failure within 4.25 days of flooding-induced seepage, whereas a levee with chimney drain was found to sustain flooding-induced seepage of 37.5 days. Geogrid-reinforced soil wall was constructed with silty sand as a structural as well as backfill, without any drainage system experienced catastrophic failure. Contrary to this, geogrid-reinforced soil walls with chimney drain as an external drainage system helped in averting catastrophic failure. However, probability of piping failure near the toe region of the wall cannot be ruled out. Further, the use of geocomposite layers as an internal drainage system within the reinforced zone also explored and the placement of geocomposite layers at one-third portion of height from bottom was found to be effective.

Lumbar Drains After Cardiac Surgery: Evidence-Based Solutions for Safe Management.

Lumbar Drains After Cardiac Surgery: Evidence-Based Solutions for Safe Management.

Pliocene endorheic-exhoreic drainage transition of the Cenozoic Madrid Basin (Central Spain)

Abstract Late Cenozoic landscape evolution in intracratonic basins represents an illustrative example of the interaction between surface processes, climate, lithologic and tectonics factors. Here, we model the transition from endorheic to exorheic conditions for the intracratonic Madrid Basin (Tagus Basin, Central Spain). During the Late Cenozoic, this basin appears to have been the result of a prolonged period of ~4.0 Ma of headward erosion by the Atlantic external drainage system, local erosion and climatic oscillations. Determining the timing of this transition is crucial to understanding the principal mechanisms of the transition course of the intracratonic basins in or associated with pop-up ridges. We present a detailed geomorphic map of the north of the Tertiary Madrid basin and new age determinations of well-preserved pediments, alluvial fans, alluvial plains and strath terraces. By combining cosmogenic ˡ0Be-26Al-21Ne with magnetostratigraphic data, the sediments associated with the last endorheic phase yield an age of ~6.4 Ma. The earliest exorheic alluvial levels of the Madrid Cenozoic basin, explained here as the first fluvial terraces, have been dated through cosmogenic nuclides depth profiles (ˡ0Be-26Al) at 2.42 Ma and 2.36 Ma respectively.

Study of Water Leakage of a Residential Building (Al-Mansheya Plaza, Khartoum - Sudan)

Water leakage affects concrete and steel buildings in general, the structure members begin collapse in the long time, and thus the building is demolished due to the effect of water leakage. This paper aimed to study of water leakage inside the basement of a seven-storey residential tower in Al-Mansheya – Khartoum state, in order to identify and solve the causes of water leakage. In this study, a borehole 10 meters deep was drilled to identify the level of groundwater, as well as a number of exploratory holes were drilled to track the impact of the leaked water, and the external drainage system units of the building were also investigated. The water leakage causes have been identified and developed a concise action plan to solve this problem as well as a number of necessary recommendations to carry out the necessary maintenance of the building.

Fly Ash Management and Condition Monitoring of Ash Pond

A thermal power plant is the most conventional source of electric power. In the thermal power plants, the coal is used as a fuel which is burnt through combustion process in boilers, and hence, ash is generated as a waste product. Ash is a major pollutant for environment and, thus, is detrimental to the animal and plant life. Also disposal of huge quantity of ash is a burning problem due to non-availability of land. Therefore, an ash pond is essential for the disposal of ash generated in a thermal power station. The ash pond consists of a large pond with ring embankment all around, internal and external drainage system, and toe protection at downstream side. The operation in ash pond takes place by filling with ash slurry, allowing the water to drain and evaporate from the pond over time. The industries are constructing ash ponds of various sizes and shapes depending upon the size and layout of available land and approval from the statutory authorities. The capacities of ponds/lagoons are being increased by raising the dyke height. For the improvement of the reliability and stability of ash ponds, it is necessary to take appropriate measures in every stages, such as designing, construction, operation, maintenance, supervision, and monitoring. Besides the constructional improvement, condition monitoring of ash pond is essential to keep it in normal operating state. This paper focuses on different condition monitoring tools and techniques to enhance the reliability of ash ponds.

Experiences with external drainage systems from compact roofs in Norwegian climates

To reduce loads on urban drainage systems and facilitate local infiltration of stormwater, it is desired to lead runoff water from roofs through external drains and into the local soil. However, in cold climates, situations often arise where water freezes in external drainpipes, damaging the pipes and preventing drainage. This article investigates the perceived feasibility of external drainage when compared against the risk of freezing damage. A literature study investigates mechanics of ice formation in drains and gutters, and under which conditions ice formation poses a risk to the building. Actors in the Norwegian building sector are interviewed about the challenges related to external drainage from compact roofs in several locations in Norway. Findings suggest that external drainage is considered feasible, but many challenges exist. Suggested solutions may conflict with building regulations, either due to risk of damages or through an unreasonably high energy consumption. Passive solutions without heating elements may, however, be feasible in certain climates in Norway. It is suggested that further research follows up the feasibility of using external drainage in relation to local climate and building concepts.

Centrifuge model studies on geocomposite reinforced soil walls subjected to seepage

This paper investigates the effect of geocomposite layers (as an internal drainage system) and a chimney sand drain (as an external drainage system) on the performance of reinforced soil walls with panel facing and marginal backfill. Four models subjected to seepage simulating a rising groundwater surface were tested at 40 gravities using a 4.5 m radius large beam centrifuge. In this study, geocomposite layers played a dual function of drainage and reinforcement. The behavior of wall models was monitored using displacement and pore water pressure transducers during centrifuge tests. An image analysis technique was also used to measure displacement and strain fields. A geogrid reinforced soil wall with no drainage system experienced catastrophic failure at the onset of seepage. Provision of geocomposite layers at the bottom portion of the wall improved the wall behavior. Further, including geocomposite layers up to the mid-height of the wall resulted in superior performance compared to geogrid-reinforced soil walls. The model with the chimney sand drain experienced piping failure at the toe of the wall. The performance of reinforced soil walls with geocomposite layers was found to be superior to the geogrid reinforced soil walls with the chimney drain.

Comparison of infection rate with tunneled vs standard external ventricular drainage: A prospective, randomized controlled trial

ObjectivesA prospective, blinded, randomized trial was performed to evaluate the incidence rates of external ventricular drainage (EVD)-related infection (ERI) after tunneled EVD (T-EVD) and standard EVD (S-EVD). Patients and methodsFrom February 2018 to February 2019, all adult patients admitted to the Union Hospital Neurosurgery Center for EVD placement were eligible for inclusion. After the application of strict exclusion criteria, all enrolled patients were randomly divided into two groups. The patients in Group A received S-EVD, and the remaining patients in Group B received T-EVD. A linear incision was made for T-EVD. The distal end of the catheter was inserted approximately 5 cm until cerebrospinal fluid was readily obtained, and then the catheter was tunneled approximately 4–5 cm from the insertion point. Finally, an external CSF drainage system was connected to the catheter. For the S-EVD patients, we secured the catheter at the original incision site after insertion, and an external CSF drainage system was also connected to the catheter. The rates of ERI were compared between the two patient groups. The odds ratios and χ² test were used to analyze the results. ResultsOne hundred twenty patients were randomly divided into two groups and underwent EVD placement. Among them, 60 patients in Group A received S-EVD, and 60 patients in Group B received T-EVD. Finally, 51 patients in Group A and 50 patients in Group B met all of the study inclusion/exclusion criteria and were thus eligible for inclusion in the evaluation of ERI rates. All clinical features of the two groups were similar. A total of 12 patients’ (11.9%) CSF cultures were positive for infection. Ten (19.6%) patients who underwent S-EVD had CSF-positive cultures, while only 2 (4.0%) patients who underwent T-EVD had CSF-positive cultures (P = 0.034). Additionally, 8 patients in Group A and 1 patient in Group B were complicated with CSF leakage (P = 0.039). ConclusionsCompared to S-EVD, T-EVD, when performed according to a previously established perioperative management protocol, resulted in lower infection and CSF leakage rates. We recommend that T-EVD should be preferentially performed when surgeons determine whether a catheter can be removed within 10 days, and the catheter used for EVD should be removed as soon as permitted by the clinical circumstances.

An Automated, Gravity-driven CSF Drainage System Decreases Complications and Lowers Costs.

Background: FlowSafeTM (BeckerSmith Medical, Irvine, CA, USA) is a novel, robotic, external lumbar drainage (ELD) system, which was designed to control cerebrospinal fluid (CSF) drainage, reduce complications, and decrease treatment costs.Methods: Forty-seven consecutive neurosurgical patients requiring ELD were treated using the FlowSafe system.Results: In 39 of 40 patients with traumatic and surgical dural openings, potential CSF leaks were avoided. In seven patients with suspected normal pressure hydrocephalus, post-infectious ventriculomegaly, or pseudotumor cerebrum, we were able to assess the likelihood of improvement with shunting. The system, therefore, produced what we considered to be the “desired result” in 46 of 47 patients (98%). Our one treatment failure (2%) involved a patient with unrecognized hydrocephalus who, following a Chiari repair with a dural patch graft, was drained for six days. A persistent CSF leak eventually required a reoperation. Two patients (4%) described low-pressure headaches during treatment. Both responded to temporarily suspending or reducing the drainage rate. We saw no complications. Required nursing interventions were minimal. Conclusions: The FlowSafe system was safe and effective. In our experience, there were fewer complications compared to currently available ELD systems. The FlowSafe was well tolerated by our patients. The near elimination of nursing interventions should allow lumbar drainage to be delivered in less costly, non-intensive care unit settings. Larger trials will be needed.

Ureteral Stent Insertion in the Management of Renal Colic during Pregnancy.

To determine an optimal invasive intervention for renal colic patients during pregnancy after conservative treatments have been found to be unhelpful. Among the available invasive interventions, we investigated the reliability of a ureteral stent insertion, which is considered the least invasive intervention during pregnancy. Between June 2006 and February 2015, a total of 826 pregnant patients came to the emergency room or urology outpatient department, and 39 of these patients had renal colic. The mean patient age was 30.49 years. In this retrospective cohort study, the charts of the patients were reviewed to collect data that included age, symptoms, the lateralities and locations of urolithiasis, trimester, pain following treatment and pregnancy complications. Based on ultrasonography diagnoses, 13 patients had urolithiasis, and 13 patients had hydronephrosis without definite echogenicity of the ureteral calculi. Conservative treatments were successful in 25 patients. Among these treatments, antibiotics were used in 15 patients, and the remaining patients received only hydration and analgesics without antibiotics. Several urological interventions were required in 14 patients. The most common intervention was ureteral stent insertion, which was performed in 13 patients to treat hydronephrosis or urolithiasis. The patients' pain was relieved following these interventions. Only one patient received percutaneous nephrostomy due to pyonephrosis. No pregnancy complications were noted. Ureteral stent insertion is regarded as a reliable and stable first-line urological intervention for pregnant patients with renal colic following conservative treatments. Ureteral stent insertion has been found to be equally effective and safe as percutaneous nephrostomy, which is associated with complications that include bleeding and dislocation, and the inconvenience of using external drainage system.

A programmable point-of-care device for external CSF drainage and monitoring.

This paper presents a prototype of a programmable cerebrospinal fluid (CSF) external drainage system that can accurately measure the dispensed fluid volume. It is based on using a miniature spectrophotometer to collect color data to inform drain rate and pressure monitoring. The prototype was machined with 1 μm dimensional accuracy. The current device can reliably monitor the total accumulated fluid volume, the drain rate, the programmed pressure, and the pressure read from the sensor. Device requirements, fabrication processes, and preliminary results with an experimental set-up are also presented.

Pediatric Frontal Mucocele Secondary to a Bifid Frontal Sinus Septum

A mucocele is a mucus-containing sac lined with epithelium that arises within a sinus when its drainage is compromised. The frontal sinus is the most common location, with frontal mucocele development occurring when the nasofrontal duct becomes obstructed because of polyps, bone tumors, prior surgery, sinusitis, trauma, or anatomic variation. We report an unusual case of a sterile pediatric frontal mucocele presenting as a slowly enlarging forehead mass due to a bifid frontal sinus septum. A 9-year-old girl presented to the craniofacial clinic for evaluation of a right frontal mass that had been slowly growing over the past year. She was otherwise healthy and had no history of previous trauma or sinus infections. Computed tomography (CT) scan results revealed a localized frontal fluid collection with protrusion and thinning of the anterior frontal bone between 2 midline bony septii. Surgical cranialization of the frontal sinus was performed. The anatomy of her lesion seen both on CT scan and intraoperatively likely explains this unusual case presentation. Instead of the usual inciting event of an intact frontal sinus drainage system becoming blocked, this patient seemed to have a primary developmental lack of any drainage system that led to her mucocele. During formation of her frontal sinus, she developed a bifid septum within the midline that excluded a portion of her frontal sinus from the lateral nasofrontal ducts. With mucus-producing epithelium trapped within these bony confines, pressure began to mount with expansion and thinning of the bone both anteriorly and posteriorly. The lack of any infectious symptoms and sterile culture results may support that this space developed primarily and was never in continuity with the external drainage system. Only 4 other patients have been reported with asymptomatic forehead swelling as the only presenting symptom, with the age ranging from 33 to 79 years. This patient represents the first clinical report of a congenital developmental mucocele.

Glaukomdrainagesystem nach Molteno bei therapieresistentem Glaukom - eine zweizeitige Operationstechnik zur Vermeidung einer postoperativen Hypotonie

The treatment of therapy-resistant secondary glaucoma with cyclodestructive approaches may give rise to unsatisfactory intraocular pressure results, leading to phthisis. A final option may be the implantation of an external glaucoma drainage system (GDS). A consecutive positioning of the drainage system under the conjunctiva and implantation of the drainage tube into the anterior chamber, may result in an uncontrolled reduced of intraocular pressure leading to intraocular haemorrhages into the anterior chamber or vitreous cavity. In particular, expulsive haemorrhages are feared as deleterious complication. 15 patients (15 eyes) with secondary glaucoma received a GDS. All patients were previously unsuccessfully treated by numerous approaches (mean 2.7 times). The mean preoperative intraocular pressure was 37 mmHg (range: 22 to 55 mmHg). We performed a sequential approach: during the first operation we implanted and fixed the resorption site of a Molteno GDS onto the sclera close to the equator in the superotemporal quadrant. After an inflammation-free interval of 2 - 3 weeks we placed the drainage tube into the anterior chamber. The average postoperative follow-up period was 20.5 months (range: 3 to 62 months). The implantation of the GDS using a sequential approach was well tolerated by all patients. While 14 out of 15 eyes achieved an IOP of 15 mmHg (range: 12 to 18 mmHg), 2 of them still required additional topical glaucoma treatment. An unsatisfactory IOP regulation was observed in only one eye although a revision surgery was performed postoperatively. Four eyes developed a light anterior chamber haemorrhage that resorbed without serious complications within 3 weeks. A choroidal effusion in one eye was treated by an anterior chamber injection of a viscoelastic gel. The potential disadvantage of the GDS can be almost completely avoided using a sequential approach. The implant heals well in the subtenon space during the first postoperative week, thus preventing an overfiltration of anterior chamber fluid. Our positive results show that the GDS is an important treatment option in selected patients.

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Endoscopic Third Ventriculostomy for Occlusive Hydrocephalus Caused by Cerebellar Infarction

The surgical management of occlusive hydrocephalus caused by massive cerebellar infarction remains controversial. The procedures that are more commonly used to avoid progressive neurological deterioration are based on transient external ventricular drainage or the placement of permanent shunt systems. To our knowledge, this is the first report regarding using endoscopic third ventriculostomy (ETV) in patients with an occlusive hydrocephalus caused by cerebellar ischemic stroke. We report our experience of 10 reviewed cases. Between 1997 and 2004, 10 patients with a resulting hydrocephalus caused by a space-occupying cerebellar infarction were managed with ETV. Glasgow Coma Scale score on admission, cause of stroke, and computed tomographic signs, including the ischemic vascular territory involved and brain edema, were noted. Clinical outcome was evaluated using the Glasgow Outcome Scale. In all patients, there was a mean interval of 4 days from the onset of deterioration of consciousness to operation. Mean Glasgow Coma Scale score on admission was 11.2. In nine patients, ETV was the initial procedure of ventricular drainage. One patient was primarily treated with an external ventricular drainage, but the device dislocated and ETV was performed. In one patient, an external ventricular drainage became necessary 7 days after the initial ETV because of a malfunction of the stoma. One patient showed a progressive brain edema 2 days after ETV, and suboccipital decompression was performed. Eight successfully treated patients demonstrated an improvement in the level of consciousness after ETV. Mean Glasgow Outcome Scale score on discharge of all patients was 3.4. Occlusive hydrocephalus caused by cerebellar infarction is infrequent. When occlusive hydrocephalus is observed, ETV can be used successfully with minimal risks, especially with avoidance of a higher rate of infectious complications caused by external drainage systems.

Near-miss Injection of an Anesthetic Agent into a Cerebrospinal Fluid External Ventricular Drain: Special Report

Human error has been increasingly recognized as a cause of patient morbidity and mortality. One method of error prevention is the reporting of a near-miss event. We report that intravenous anesthetic agents were nearly injected into the external ventricular drainage (EVD) of a patient during an emergency shunt procedure. A 3-year-old male patient with multiple cerebrospinal fluid shunts and shunt infection had an external ventricular drain catheter tunneled to exit just inferior to the left clavicle during a previous procedure. The exit site was covered by an occlusive dressing. This particular system, the Codman external drainage system II collection bag and tubing set (Codman & Shurtleff, Inc., Raynham, MA), contains two access ports (a three-way stoppered port and an angled rubber stoppered injection port). At induction of anesthesia, the EVD system was mistaken for a central venous line and was nearly injected with propofol and rocuronium. Fortunately, the error was quickly recognized and the patient came to no harm. A modified EVD system has recently been released that does not include the three-way port, and features an embedded bright green stripe in the tubing to distinguish it from intravenous tubing. We recommend using caution when tunneling EVDs to sites that might be confused with central venous access sites. EVD system tubing should be designed so it can be easily distinguished from intravenous tubing, and it should be clearly labeled as an EVD line.

Third ventriculostomy through the lamina terminalis for intracranial pressure monitoring after aneurysm surgery: technical note.

A new ventriculostomy technique through the lamina terminalis is described. This technique is applied mainly during aneurysm surgery at the acute stage. Thirteen patients were operated on intracranial aneurysms and, during the procedure, had the lamina terminalis fenestrated. A ventricular catheter was inserted into the third ventricule, left in place and connected to an external drainage system for further intracranial pressure (ICP) monitoring and/or cerebrospinal fluid (CSF) drainage. ICP readings and CSF drainage were obtained in all cases. No complication was recorded. Third ventriculostomy through the lamina terminalis is a simple and easy technique that can be used as an alternative to conventional ventriculostomy. This procedure can be indicated in cases where the ventricule is not reached by means of another technique, and when the decision to perform ventriculostomy is made at the end of aneurysm surgery.