Calculation of 6-Hour Dip Creatinine Ratio from the 4-Hour Peritoneal Equilibration Test. The Effect of Dwell Duration on the Results

1997 ◽  
Vol 17 (3) ◽  
pp. 273-278 ◽  
Author(s):  
Rajnish Mehrotra ◽  
Ramesh Khanna ◽  
Thomas C.K. Yang ◽  
Pranay Kathuria ◽  
Harold L. Moore ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Peritoneal Dialysis ◽  
University Hospital ◽  
Published Data ◽  
Peritoneal Equilibration Test ◽  
Cardiovascular Research ◽  
Proposed Model ◽  
Margin Of Error ◽  
The University ◽  
Exponential Relation

Objectives Since the introduction of the peritoneal equilibration test (PET), the 4-hour dialysatelplasma creatinine (DIP Cr) has been used by several authors for determining continuous ambulatory peritoneal dialysis (CAPD) prescriptions. However, the results have been unsatisfactory because the 4-hr DIP Cr does not accurately reflect the DIP Cr in 24-hr collections. The PET and the 24-hr dialysate collections differ in the duration of dwell and the tonicity and volume of dialysate, all of which influence the equilibrated DIP Cr. It can be assumed that the DIP Cr in 24-hr collections in these patients is closer to a 6-hr DIP Cr. Because a 6hr PET is inconvenient, we developed a mathematical model to calculate the 5 and 6-hr DIP using the results of a standard PET. Design In a retrospective analysis, DIP Cr ratios in 24-hr collections and DIP Cr ratios calculated from a mathematical formula were correlated. Using a mathematical model, the data collected fit an exponential relation of the type DIP = a(1 -e-t/τ). The values of a and τ are unique for a given patient and were determined using a nonlinear regression technique. The formula performed well on our published data -the true and predicted 6-hr DIP Cr being 0.696 and 0.71, respectively. Setting The University Hospital and Clinics, Dalton Cardiovascular Research Center and Dialysis Clinic, Inc., Columbia, Missouri. Patients All CAPD patients on four 2-L exchangeslday at the time of the 24-hr collections were included. Interventions None. Main Outcome Measures Closeness of 4-hr and 6-hr DIP Cr values to those of 24-hr ratios. Results The study group comprised 74 patients (age, mean ± SEM: 56.4 ± 1.8 yr) with 80 PETs and 145 (24-hr) collections. The interval between the two tests was 8. 3 ± 0.9 months (0 48.7 months). The median 24-hr DIP Cr of 0.760 did not differ significantly from the predicted median 6-hr DIP Cr of 0.755. A subgroup analysis, based on transport type, showed that this relationship was most precise in the high-average transporters. The predicted 6hr DIP Cr was within 100;0 of the 24-hr DIP Cr in 48% of patients and within 20% in 77% of patients. The margin of error was greatest in the low transporters. Conclusions To conclude, the 4-hr DIP Cr from a PET cannot be used interchangeably with the DIP Cr in the 24-hr dialysate collections, hence, the clearances calculated thereof will be inaccurate. Using the proposed model, it is feasible to use the 4 -hr PET results to obtain 5 and 6 -hr DIP Cr values. In our study, using this model, the extrapolated 6-hr DIP Cr is similar to the DIP Cr in 24-hr dialysate collections only in the high-average transporters. Hence, the best way to determine clearances in peritoneal dialysis patients is still by collecting 24-hr dialysates.

THE DEVELOPMENT OF THE MATHEMATICAL MODEL OF PREDICTING THE INDICATORS OF ACCREDITATION OF TECHNICAL UNIVERSITIES IN THE RUSSIAN FEDERATION

2017 ◽  
pp. 27-38
Author(s):  
Olga Mikhaylovna Tikhonova ◽  
Alexander Fedorovich Rezchikov ◽  
Vladimir Andreevich Ivashchenko ◽  
Vadim Alekseevich Kushnikov
Keyword(s):  
Mathematical Model ◽  
System Dynamics ◽  
Regression Model ◽  
Oriented Graph ◽  
Real Data ◽  
Educational Process ◽  
Proposed Model ◽  
Linear Differential ◽  
The University ◽  
The Mathematical Model

The paper presents the system of predicting the indicators of accreditation of technical universities based on J. Forrester mechanism of system dynamics. According to analysis of cause-and-effect relationships between selected variables of the system (indicators of accreditation of the university) there was built the oriented graph. The complex of mathematical models developed to control the quality of training engineers in Russian higher educational institutions is based on this graph. The article presents an algorithm for constructing a model using one of the simulated variables as an example. The model is a system of non-linear differential equations, the modelling characteristics of the educational process being determined according to the solution of this system. The proposed algorithm for calculating these indicators is based on the system dynamics model and the regression model. The mathematical model is constructed on the basis of the model of system dynamics, which is further tested for compliance with real data using the regression model. The regression model is built on the available statistical data accumulated during the period of the university's work. The proposed approach is aimed at solving complex problems of managing the educational process in universities. The structure of the proposed model repeats the structure of cause-effect relationships in the system, and also provides the person responsible for managing quality control with the ability to quickly and adequately assess the performance of the system.

Results of Peritoneal Equilibration Test during Treatment with Polyglucose Dialysis Solution

2002 ◽  
Vol 22 (3) ◽  
pp. 357-364 ◽  
Author(s):  
Alicja E. Grzegorzewska ◽  
Danuta Antczak-Jȩdrzejczak ◽  
Magdalena Leander
Keyword(s):  
Peritoneal Dialysis ◽  
Dwell Time ◽  
Control Period ◽  
University Hospital ◽  
Control Group ◽  
Peritoneal Equilibration Test ◽  
Dialysis Unit ◽  
Dialysis Solution ◽  
Glucose Ratio ◽  
Peritoneal Permeability

Background Results of peritoneal equilibration test (PET) suggest prolonged effect of polyglucose dialysis solution (PG-DS) on peritoneal permeability. Objectives An evaluation of dialysate-to-plasma ratio (D/P) of urea, D/P creatinine, and D/D0 glucose (ratio of dialysate glucose at designated dwell time to dialysate glucose at 0 dwell time), and mass transfer area coefficients (KBD) of these solutes in PET before introduction, during administration, and after discontinuation of PG-DS in patients treated with continuous ambulatory peritoneal dialysis (CAPD). Design Single-center prospective study with PG-DS; retrospective selection of the control group. Setting Peritoneal dialysis unit in a university hospital. Patients Fourteen patients (11 males; age 45.1 ± 8.5 years) treated with CAPD for 17.5 ± 9.9 months. 7.5% PG-DS was used for the overnight exchange. After discontinuation of the PG-DS, standard dialysis solutions, as previously used, were reintroduced. The control group was selected to match both CAPD duration and peritoneal permeability of the patients in the PG-DS group at the start of the study. Methods Standard PET was carried out at 1.6 ± 0.8 months before the introduction of PG-DS (study period I, n = 14), after 1.2 ± 0.6 months’ use of PG-DS (study period II, n = 14), after 4.4 ± 0.8 months’ use of PG-DS (study period III, n = 11), after 8.8 ± 2.2 months’ use of PG-DS (study period IV, n = 9), and at 2.0 ± 0.6 months after PG-DS discontinuation (study period V, n = 11). Patients in the control group underwent PET at similar time intervals (control periods I – V). Results In the PG-DS group, a tendency toward increased peritoneal permeability for urea and creatinine was shown during the consecutive study periods. D/D0 glucose was significantly higher only in the PET performed during use of PG-DS (periods II – IV) compared to results obtained in period I. In the control group, both D/P and KBD of both urea and creatinine remained unchanged, but KBD glucose was higher in the first 2 hours of the PET in control period V compared to respective values in control period III. Conclusion Changes in peritoneal permeability are observed in CAPD patients treated with PG-DS. These changes may be at least partially related to the administration of polyglucose.

Compliance Study in Peritoneal Dialysis Using Pdadequest Software

1996 ◽  
Vol 16 (1_suppl) ◽  
pp. 176-178 ◽  
Author(s):  
Gianpaolo Amici ◽  
Giusto Viglino ◽  
Giovambattista Virga ◽  
Carmen Gandolfo ◽  
Giorgio Da Rin ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Peritoneal Dialysis ◽  
Filtration Rate ◽  
Threshold Value ◽  
Control Group ◽  
Case Histories ◽  
Peritoneal Equilibration Test ◽  
Software Model ◽  
Noncompliant Patient ◽  
The Mean

Poor compliance in peritoneal dialysis (PD) is a significant cause of dropout and morbidity. PD Adequest software, which, through a mathematical model, predicts the effect of the dialysis prescription on the basis of the peritoneal transport, may be used to identify the noncompliant patient. Fifty patients from two dialysis centers, aged 65.9±1.5 years and on PD for 28.6±4.7 months, were studied. A peritoneal equilibration test (PET) was carried out and 24hour urine and dialysate were collected. Total weekly creatinine clearance (CrCI, L/week/1.73 m2) was calculated, as well as the glomerular filtration rate [(GFR), mL/min, mean CrCI and urea nitrogen clearance (UNCI)]. The dialytic schedules used were then introduced into the program and the parameters were recalculated using the software model. Nine patients considered noncompliant from their case histories were used to assess the differences of reference between expected and measured values. The control group was significantly different from the noncompliant group in the percentage of the CrCI and the serum creatinine (sCR) differences. The noncompliance threshold value was calculated from the mean of the lower 95% confidence interval of the compliant group and the higher one of the noncompliant group (-5.3%) for CrCI and vice versa for sCR (+10%), which behaved to the contrary. Reassessing the patients, 11 (22%) were identified as probably noncompliant.

scholarly journals Development of mathematical model of logistics humanitarian assistance with resilience to risk management in earthquakes and earthquakes in Caqueza, Cundinamarca

2019 ◽  
Vol 15 (1) ◽  
pp. 1-33
Author(s):  
José Eduardo Barragán Acevedo ◽  
Ludwig Ben Roald Castañeda Tenjo ◽  
Ever Ángel Fuentes
Keyword(s):  
Mathematical Model ◽  
Risk Management ◽  
Logistic Model ◽  
Humanitarian Logistics ◽  
Humanitarian Assistance ◽  
Management Scenario ◽  
Proposed Model ◽  
Resilience Index ◽  
The University ◽  
Post Disaster

Introduction: the article is the product of the research “Development of a mathematical model of humanitaria logistics with resilience for risk management in earthquakes and earthquakes in Cádiz, Cundinamarca”, deveped during 2017 and 2018, in the Faculty of Industrial Engineering of the University Free in Colombia.Problem: the municipality of Cáqueza, due to its geographical characteristics, presents vulnerability to earth-quakes and does not have a post-disaster logistic plan in accordance with the risk needs of its inhabitants.Objective: to develop a mathematical model of humanitarian logistics with resilience for risk management in earthquakes in Cávelo, Cundinamarca.Methodology: diagnosis and measurement of the community resilience index in Cabala to propose a model of humanitarian logistics. The parameters, variables and restrictions are described and validated through computer tools such as Open Solver and Promodel.Results: a humanitarian logistic model was developed that responds to the reality of the municipality by determing the ideal way to transport, store and distribute provisions to a population with resilient demand.Conclusion: a tool is generated that provides the Cábala community with a post-disaster logistic model according to their characteristics and needs, which allows them to react to reduce the mortality rate in the event of an earthquake.Originality: application of resilience in the risk management scenario, with the incorporation of the characteristics of the community to the mathematical models of humanitarian logistics.Limitations: the proposed model is solved from linear programming and does not take into account probabilistic variables.

scholarly journals Accidental Ingestion of Dental Bur during Dental Extraction

2019 ◽  
Vol 4 (11) ◽  
Keyword(s):  
Peritoneal Dialysis ◽  
Tooth Extraction ◽  
Chronic Kidney Failure ◽  
University Hospital ◽  
Wisdom Tooth ◽  
Accidental Ingestion ◽  
Slow Pulse ◽  
The University ◽  
Wisdom Tooth Extraction ◽  
Radiographic Investigation

A 24-year-old female patient was admitted to the dental department of the university hospital Sahloul in Sousse in November 2019 for wisdom tooth extraction. The patient had chronic kidney failure and was on peritoneal dialysis. During the extraction, the patient had accidentally ingested the dental bur (Zekrya MANI®): the bur popped out from the airotor and fell into the patient’s throat. There were no immediate symptoms such as coughing, drooling, dyspnoea or any other symptom of respiratory distress. The patient was immediately taken to the department of radiology for abdominal radiographic investigation. She was advised to be on a diet rich of fibers (especially potato) which was impossible for our patient. In fact, potato is a main source of potassium and when kidneys fail, they can no longer remove excess potassium, which leads to hyperkalemia. Some of the effects of hyperkalemia are nausea, weakness, numbness and slow pulse.

ECONOMIC TRACK MODELS OF ONTOGENESIS OF REGIONAL UNIVERSITIES

2020 ◽  
Vol 4 (12) ◽  
pp. 15-21
Author(s):  
I. V. ASHINOVA ◽  
◽  
R. V. GURFOVA ◽  
A. M. KALMYKOVA ◽  
Z. A. NAKHUSHEVA ◽  
...  
Keyword(s):  
Mathematical Model ◽  
Educational Institution ◽  
Subject Area ◽  
Main Element ◽  
Proposed Model ◽  
Regional Universities ◽  
The Subject ◽  
Fractional Differential ◽  
The University ◽  
New Formation

The article is devoted to the issues of modeling the economic processes of ontogenesis that arise in the universities of a new formation. The aim of the study is to substantiate the subject area and build a mathematical model of the economic ontogenesis of a higher educational institution of a new level, the specificity of which is the fact that an educational institution has the opportunity to become an integrator, a kind of platform for ensuring economic superiority at the regional and global levels. The subject area of the model is based on the concepts and methods of the theory of innovation. The activities of the university are considered in three spaces: the space of knowledge, the space of consent and the space of innovation. Using the methods of the theory of fractional differential equations, a continuous economic and mathematical model has been built, which, at certain values of the input parameters, has a unique solution and correctly correlates with the experimental data. The proposed model is the main element of the multi-criteria model of interaction between the university economy and the economy of the region.

Symptomatic vascular complications after vascular closure device use following diagnostic and interventional catheterisation

VASA ◽  
2004 ◽  
Vol 33 (2) ◽  
pp. 78-81 ◽  
Author(s):  
Thalhammer ◽  
Aschwanden ◽  
Jeanneret ◽  
Labs ◽  
Jäger
Keyword(s):  
Current Literature ◽  
Vascular Complications ◽  
University Hospital ◽  
Closure Device ◽  
Ultrasound Guided ◽  
Vascular Closure Device ◽  
Device Use ◽  
Arterial Stenoses ◽  
The University ◽  
Stenotic Lesions

Background: Haemostatic puncture closure devices for rapid and effective hemostasis after arterial catheterisation are a comfortable alternative to manual compression. Implanting a collagen plug against the vessel wall may become responsible for other kind of vascular injuries i.e. thrombotic or stenotic lesions and peripheral embolisation. The aim of this paper is to report our clinically relevant vascular complications after Angio-Seal® and to discuss the results in the light of the current literature. Patients and methods: We report the symptomatic vascular complications in 17 of 7376 patients undergoing diagnostic or therapeutic catheterisation between May 2000 and March 2003 at the University Hospital Basel. Results: Most patients presented with ischaemic symptoms, arterial stenoses or occlusions and thrombotic lesions (n = 14), whereas pseudoaneurysms were extremely rare (n = 3). Most patients with ischaemic lesions underwent vascular surgery and all patients with a pseudoaneurysm were successfully treated by ultrasound-guided compression. Conclusions: Severe vascular complications after Angio-Seal® are rare, consistent with the current literature. There may be a shift from pseudoaneurysms to ischaemic lesions.

User Evaluation of an Integrated Medical Workstation for Clinical Data Analysis

1993 ◽  
Vol 32 (05) ◽  
pp. 365-372 ◽  
Author(s):  
T. Timmeis ◽  
J. H. van Bemmel ◽  
E. M. van Mulligen
Keyword(s):  
Data Analysis ◽  
Clinical Research ◽  
Clinical Data ◽  
University Hospital ◽  
User Evaluation ◽  
Scientific Staff ◽  
Medical Institutions ◽  
Clinical Data Analysis ◽  
Research Problems ◽  
The University

AbstractResults are presented of the user evaluation of an integrated medical workstation for support of clinical research. Twenty-seven users were recruited from medical and scientific staff of the University Hospital Dijkzigt, the Faculty of Medicine of the Erasmus University Rotterdam, and from other Dutch medical institutions; and all were given a written, self-contained tutorial. Subsequently, an experiment was done in which six clinical data analysis problems had to be solved and an evaluation form was filled out. The aim of this user evaluation was to obtain insight in the benefits of integration for support of clinical data analysis for clinicians and biomedical researchers. The problems were divided into two sets, with gradually more complex problems. In the first set users were guided in a stepwise fashion to solve the problems. In the second set each stepwise problem had an open counterpart. During the evaluation, the workstation continuously recorded the user’s actions. From these results significant differences became apparent between clinicians and non-clinicians for the correctness (means 54% and 81%, respectively, p = 0.04), completeness (means 64% and 88%, respectively, p = 0.01), and number of problems solved (means 67% and 90%, respectively, p = 0.02). These differences were absent for the stepwise problems. Physicians tend to skip more problems than biomedical researchers. No statistically significant differences were found between users with and without clinical data analysis experience, for correctness (means 74% and 72%, respectively, p = 0.95), and completeness (means 82% and 79%, respectively, p = 0.40). It appeared that various clinical research problems can be solved easily with support of the workstation; the results of this experiment can be used as guidance for the development of the successor of this prototype workstation and serve as a reference for the assessment of next versions.

Sharing of Worldwide Spread Knowledge Using Hypermedia Facilities & Fast Communication Protocols (Mosaic and World Wide Web): The Example of ExPASy

1995 ◽  
Vol 34 (01/02) ◽  
pp. 75-78 ◽  
Author(s):  
R. D. Appel ◽  
O. Golaz ◽  
Ch. Pasquali ◽  
J.-C. Sanchez ◽  
A. Bairoch ◽  
...  
Keyword(s):  
World Wide Web ◽  
World Wide ◽  
Relevant Literature ◽  
Communication Protocols ◽  
Laboratory Data ◽  
Central Element ◽  
University Hospital ◽  
New Information ◽  
The University ◽  
Link Information

Abstract:The sharing of knowledge worldwide using hypermedia facilities and fast communication protocols (i.e., Mosaic and World Wide Web) provides a growth capacity with tremendous versatility and efficacy. The example of ExPASy, a molecular biology server developed at the University Hospital of Geneva, is striking. ExPASy provides hypermedia facilities to browse through several up-to-date biological and medical databases around the world and to link information from protein maps to genome information and diseases. Its extensive access is open through World Wide Web. Its concept could be extended to patient data including texts, laboratory data, relevant literature findings, sounds, images and movies. A new hypermedia culture is spreading very rapidly where the international fast transmission of documents is the central element. It is part of the emerging new “information society”.

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