Early postoperative complications in emergency colorectal surgery

Catedra Chirurgie nr.1 „N.Anestiadi”, USMF „Nicolae Testemiţanu”, Chişinău, Republica Moldova, Al XII-lea Congres al Asociației Chirurgilor „Nicolae Anestiadi” din Republica Moldova cu participare internațională 23-25 septembrie 2015Introducere: Complicațiile postoperatorii precoce ale cancerului colorectal operat în regim de urgență în literatura de specialitate sunt elucidate insuficient. Scopul lucrării: Studierea complicațiilor postoperatorii precoce ale cancerului colorectal operat în regim de urgență. Material și metode: Studiul cuprinde 293 pacienți operați în Institului de Medicină de Urgență în perioada anilor 2010-2014, raportul B:F=164:129, cu vîrsta între 28 și 88 ani. Chirurgia de extirpare a tumorii a fost posibilă la 277 pacienți (94,5%): cu restabilirea primară a tranzitului intestinal în 63,2% (175) cazuri, iar aplicarea stomelor – în 36,8% (102). În 5,5% (16) cazuri au fost impuse intervențiile paliative. Rezultate: Rata totală a complicațiilor postoperatorii precoce a constituit 85,7%. Au fost 87 complicații dependente de actul operator: supurarea plăgii laparotomice (11,6%), abcese parastomale (6,7%), dehiscențe anastomotice (8,25%), eventrații ale plăgii laparotomice (8,25%), retracția stomei (1,0%), necroza stomei (1,0%), dehiscența bontului rectal (0,52%), eviscerația parastomală (0,52%), flegmon al peretelui abdominal (0,52%), fistula parastomală (0,52%). Complicațiile postoperatorii generale s-au întîlnit în 164 cazuri, alcătuind: MODS (20,62%), pneumonii (20,1%), infecții urinare (5,2%), insuficiență cardiacă (3,6%), edeme pulmonare (2,6%), embolii pulmonare (2,1%), infarct miocardic (1,0%). Concluzii: Cele mai frecvente complicații postintervenționale legate de actul operator aparțin supurației plăgii laparotomice (17,5%), eventrației (8,25%), dehiscenței anastomotice (8,25%), abcesului parastomal (6,7%), iar cele de ordin general – MODS (20,6%) și afecțiunilor pulmonare (20,1%).There are few data in the literature on early postoperative complications in emergency colorectal surgery. Aim of study To assess the early postoperative complications in emergency colorectal surgery. Material and method. This is a 5-year (2010-2014) analysis of 293 patients aged between 28 and 88 years old, the sex ratioM W being 164 129, who underwent emergency surgery for colorectal cancer in the surgical department of the Emergency Medical Institute. Colon resection surgery was possible in 277 patients (94.5%), including primary restoration of the intestinal transit in 63.2% (175) cases and 36.8% (102) cases of stoma creation. Only 16 (5.5%) patients underwent palliative surgery. Results The global rate of early postoperative complications was 85.7%. There were 87 complications specific to the type of surgery, undertaken laparotomic wound supuration (11.6%), peristomal abscess (6.7%), anastomotic leak (8.25%), laparotomicwound eventration (8.25%), stoma retraction (1.0%), stoma necrosis (1.0%), rectal stump dehiscence (0.52%), parastomalevisceration (0.52%), phlegmon of the anterior abdominal wall (0.52%), peristomal fistulae (0.52%). Common general postoperative complications were found in 164 cases, including MODS (20.62%), pneumonia (20.1%), urinary tract infections(5.2%), cardiac failure (3.6%), pulmonary edema (2.6%), pulmonary embolism (2.1%), heart attack (1.0%). Conclusion The most frequent complications specific to the type of surgery undertaken were laparotomic wound supuration(11.6%), anastomotic dehiscence (8.25%), laparotomic wound event ration (8.25%), peristomal abscess (6.7%), and the common general postoperative complications were MODS (20.62%) and pneumonia (20.1%)

Mathematical Model of Electrical Line with Transposition of Phase Circuits

The purpose of this paper is to elaborate the mathematical model and the method of calculation of the permanent regime in the line with many conductors with transposed phases. The mathematical model is based on the telegraph equations and takes into account the fact that the electric lines are lines with distributed parameters. As a subject of the study it is selected the 110 kV overhead power line with two compact circuits with the conductors placed horizontally and circularly transposed. The initial and boundary conditions are formulated for the case of two-circuit electric line and the adjustment of the phase angle of the voltages at the line input. In the transposition the values of the conductor parameters change by leap, which complicates the process of calculating the operating mode. The developed model and elaborated software include all these features. Based on the developed model, calculations of the operating mode of the two-circuit electric circuit and of the self-compensated line were performed. Numerical solutions have been obtained regarding the evolution of active and reactive power in the phases of the line in its various sections under regulation and non-regulation of the phase shift angle for the cases without and with the transposition of the phase conductors. The applicability of the model for studying power transfer processes in multi-conductor power lines has been demonstrated. There were obtained the numerical solutions useful for estimating the degree of mutual influence of phases on the ability to transfer power to load under the transposition of conductors

REACTIVE POWER IN THE LONG ELECTRICAL LINES

This paper presents a numerical method for the calculation of electric circuits with distributed parameters with losses that may vary over time. It is proposed to use the energy integral in order to estimate the accuracy of numerical solutions. The elaborated numerical scheme, named Albatross, is conservative with minimal dissipation and dispersion. These properties lead to the fact that the computational error does not accumulate, that gives the possibility to realize the transparent calculations of non stationary solutions without loss of accuracy at large time intervals corresponding to 300…500 electromagnetic wave runs along the line length right up to steady-state regime. The results of calculations for non-homogeneous circuits with distributed parameters are presented graphically. These results can be used as a model to develop new approximate methods for numerical solution of electrotechnical problems. The solutions of these problems have been obtained by means of operator method, complex amplitude method, Fourier method as well as by numerical method Albatross. The results of calculations for various modes in the half-wave transmission line are represented. The comparison between the physical and mathematical experiments in analyzing of different regimes in half-wave electrical transmission line is represented. The comparison of accuracy of the solutions obtained by proposed method, by Finite Difference Time Domain (FDTD) method and by Godunov’s scheme for telegraph equations is carried out. It is illustrated, that FDTD method has some limited application for solving the telegraph equations in spite of the fact that it is of second order of accuracy

ABOUT SOME FEATURES OF TRANSMISSION MODE FOR ACTIVE POWER OF ELECTRICAL LINE

This paperwork examines the problem of maximum power transfer to the load of a long line mode change from idle line (XX ) to short-circuit ( SC). Load line changes from idle mode (IM ) to its short-circuit (SC ). The line length varies from zero up to a length equal to the physical length of the electromagnetic wave. As a method of research it is used the method of the complex amplitudes (MCA). As independent variables were examined her load line length and that the system per unit change in the band plus minus unit to unit , so . It enteritis that for the active character load of the active power input and power output of the line, so functions , and functions that characterize developments efficiency , power factor at the input line and the load power factor when the variable z. For these points to the notion of critical value of the load . It founds the effect of " recession " critical resistance values and functions şi , which is not found for the other functions considered - efficiency and power factor. Load reactive power compensation can help to increase power output only for lines with length smaller than ¼ wave length electromagnitice wave. In non-distortional lines, such effect is not observed. The paper work represents the general data transmission mode the maximum power lines of different lengths to the load, which varies from idle mode (IM) to short-circuit (SC) regime. These data can be used for preliminary analysis of the efficiency of the electrical lines at variable load

A Generalized Approach to the Calculation Procedure of Distribution Network Steady-state and Transient Regime

The low-voltage electrical distribution networks are characterized by ramified topology and spatial distribution of the consumers connected to the power supply. This leads to certain difficulties in calculation of such circuits even in the case of steady state mode, since even in stationary case a new separate problem must be solved each time. We have to mention that these difficulties are even more pronounced in the case of the circuit transient analysis. This paper proposes a generalized approach to calculation of steady-state and transient regimes in the branched distribution networks with RLC loads. To solve this problem we propose to use the mesh currents method, representation of the system of equations in matrix form and the Laplace transform. This gives the possibility to determine the characteristics of the current and voltage changes over time in the network and in the load. The difference between the obtained results and the known results, published in the open sources, is determined by the fact that the calculation of stationary and transient modes, is performed using the same calculations algorithm for both stationary and transient regimes

Zero-voltage and Zero-current-switching of Half-bridge PWM Converter for High Power Applications

The design and control of a half-bridge converter that ensures zero voltage and zero current shifting of electronic switches throughout the load band for a large range of input voltage is described in this paper. The new proposed topology of the converter achieves a substantial reduction of losses due to the shifting of electronic switches and oscillating currents. The proposed topology has a simple technical scheme with minimal number of control elements with a total low price, as well. The control of the proposed converter can be implemented by applying the technique of pulse width modulation (PWM). The functionality, stability and performance of the proposed converter topology have been verified on an experimental converter at power range 420 W (400V, 50V)

A Comparative Analysis of the Efficiency of Thermal and Electric Energy Production in the District Heating Systems

In the base of the technical and economic indicators of the exploitation, an analysis of the efficiency of operation of Combined Heat and Power stations (CHP) in the district heating system at various loads during the year have been provided. The value of specific indicators of operation of the CHPs have been determined: a specific consumption of the fuel, the cost of the fuel per unit of energy produced, as well as the difference between the selling price of energy and acquisition costs of the fuel. As have been found, the optimization of CHP’s of the district heating loading during the year in the Chisinau municipality can offer an economic benefit amounted at 13-19 mln. lei MD in comparison with the current practice of CHP’s generation capacity use

ASPECTS OF THE PROBLEM OF INCENTIVES FOR IMPLEMENTATION OF HEAT PUMPS

There were identified reasons for incentives of the implementation of heat pumps by the Governement of industial developped countries. It is considered scheme of obtaining of benefits for the Governement as a result of heat pump incentives