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3.
J.health med.sci. ; 9(3): 51-63, jul.2023. ilus, graf, tab
Article in English | LILACS | ID: biblio-1524683

ABSTRACT

INTRODUCTION Radiobiological-based optimization functions for radiotherapy treatment planning involve dose-volume effects that could allow greater versatility when shaping dose distributions and DVHs than traditional dose volume (DV) criteria. Two of the most commercially available TPS (Monaco and Eclipse) already offer biological-based optimization functions, but they are not routinely used by most planners in clinical practice. Insight into the benefits of using EUD, TCP/NTCP-based cost functions in Monaco and Eclipse TPS was gained by comparing biological-based optimizations and physical-based optimizations for prostate and head and neck cases. METHODS Three prostate and three H&N cases were retrospectively optimized in Monaco and Eclipse TPS, using radiobiological-based cost functions vs DV-based cost functions. Plan comparison involved ICRU Report 83 parameters D95%, D50%, D2% and TCP for the PTV, and NTCP and RTOG tolerance doses for OARs. RESULTS Although there were differences between Monaco and Eclipse plans due to their dissimilar optimization and dose calculation algorithms as well as optimization functions, both TPS showed that radiobiological-based criteria allow versatile tailoring of the DVH with variation of only one parameter and at most two cost functions, in contrast to the use of three to four DV-based criteria to reach a similar result. CONCLUSION Despite the use of a small sample, optimization of three prostate and three head and neck cases allowed the exploration of optimization possibilities offered by two of the most commercially available TPS on two anatomically dissimilar regions. Radiobiological-based optimization efficiently drives dose distributions and DVH shaping for OARs without sacrifice of PTV coverage. Use of EUD-based cost functions should be encouraged in addition to DV cost functions to obtain the best possible plan in daily clinical practice


INTRODUCCION Las funciones de optimización basadas en radiobiología para la planificación del tratamiento de radioterapia implican efectos dosis volumen que podrían permitir una mayor versatilidad a la hora de dar forma a las distribuciones de dosis y DVH que los tradicionales criterios dosis-volumen (DV). Dos de los TPS más disponibles comercialmente (Mónaco y Eclipse) ya ofrecen productos de funciones de optimización de base biológica, pero la mayoría de los planificadores no las utilizan de forma rutinaria en la práctica clínica. El conocimiento de los beneficios del uso de las funciones de costos basadas en EUD, TCP/NTCP en Mónaco y Eclipse TPS se obtuvo comparando optimizaciones de base biológica y optimizaciones físicas para casos de próstata y cabeza y cuello. MÉTODOS Tres próstatas y tres casos de H&N en Mónaco y Eclipse TPS fueron optimizadas retrospectivamente usando funciones de costos basadas en radiobiología vs funciones de costos basadas en DV. La comparación de planes involucró los parámetros del Informe ICRU 83 D95%, D50%, D2% y TCP para el PTV, y dosis de tolerancia NTCP y RTOG para OAR. Resultados. Aunque hubo diferencias entre los planes Mónaco y Eclipse, debido a sus diferentes algoritmos de optimización y cálculo de dosis, así como funciones de optimización, ambos TPS demostraron que el criterio basado en radiobiología permiten una adaptación versátil del DVH con variación de un solo parámetro y como máximo dos funciones de costos, en contraste con el uso de tres o cuatro criterios basados en DV para alcanzar un resultado similar. CONCLUSIÓN A pesar del uso de una muestra pequeña, la optimización de tres casos de próstata y tres de cabeza y cuello permitió la exploración de las posibilidades de optimización que ofrecen dos de los TPS más disponibles comercialmente en dos regiones anatómicamente diferentes. La optimización basada en radiobiología impulsa de manera eficiente las distribuciones de dosis y la configuración de DVH para OAR sin sacrificar Cobertura de PTV. Se debe fomentar el uso de funciones de costos basadas en EUD además de las funciones de costos DV para obtener el mejor posible plan en la práctica clínica diaria


Subject(s)
Radiobiology/methods , Radiotherapy Dosage , Radiotherapy Planning, Computer-Assisted , Prostate/diagnostic imaging , Software Validation , Head/diagnostic imaging , Neck/diagnostic imaging
4.
Article in Spanish | MEDLINE | ID: mdl-23177530

ABSTRACT

This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.

5.
J Cardiovasc Surg (Torino) ; 53(2): 257-63, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22456650

ABSTRACT

AIM: The radial artery has become the artery of choice after the internal thoracic artery for coronary artery bypass grafting (CABG). This study compares wound healing and arm complications after endoscopic versus open radial artery harvesting for CABG. METHODS: From January 2002 to July 2004, 509 patients underwent CABG in which a radial artery conduit was used. Thirty-nine had endoscopic and 470 had conventional open radial artery harvesting. A propensity score was used to obtain 1:3 matching of all endoscopic to 117 open-harvesting patients. Postoperative wound healing using the Hollander scale, local neurologic deficits, wound infection, and pain scores were compared. RESULTS: Wound healing: 34 of 39 endoscopic wounds exhibited a perfect Hollander score versus 339 of 470 open-harvest wounds (P=0.01). Wound appearance in particular was better than for open harvesting (P=0.004), with no abnormal step-off borders, irregular contours, or abnormal scar width observed. Neurologic deficits. Three incomplete neurologic deficits were observed after open harvesting (two being distal sensitivity localized in the interspace between the first and second metacarpals); one complete neurologic deficit occurred after endoscopic harvesting, but improved remarkably prior to hospital discharge. Wound infection. Occurrence of wound infection was similar in the two groups (P=0.7), although infection was more severe with open harvesting. Pain: pain score was lower (P=0.006) with endoscopic harvesting. CONCLUSION: Compared with conventional open harvesting, endoscopic radial artery harvesting was associated with better wound appearance and less pain. Occurrence of neurologic deficits and wound infection was infrequent in both groups.


Subject(s)
Coronary Artery Bypass/methods , Endovascular Procedures/methods , Myocardial Ischemia/surgery , Radial Artery/transplantation , Tissue and Organ Harvesting/methods , Female , Follow-Up Studies , Humans , Male , Middle Aged , Postoperative Complications/prevention & control , Retrospective Studies , Treatment Outcome
6.
Water Environ Res ; 83(2): 162-72, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21449478

ABSTRACT

For activated sludge modeling purposes, the methods used to evaluate the readily biodegradable chemical oxygen demand (RBCOD) in the influents are by biological or via physicochemical assays. However, there has not been sufficient wide comparison between these methods. The main goal of this study was to investigate the performance of the main chemical oxygen demand (COD) fractionation protocols, considering a representative wastewater in the context of tropical and developing countries. Different physicochemical characterization procedures, respirometric tests, and chemical analyses were performed. The fate of the soluble COD in the aeration tanks was studied. The results of the study showed that a marked difference may exist, in municipal wastewaters, between the estimates of the RBCOD fractions measured by respirometry and by any of the physicochemical methods. The evaluated influent showed a rather large fraction of COD that was passing the filters without being rapidly biodegradable, but which was removed quickly by enmeshment in the bioflocs. The consequences of such divergences and behavior are discussed.


Subject(s)
Biodegradation, Environmental , Bioreactors , Oxygen Consumption/physiology , Waste Disposal, Fluid , Environmental Monitoring , Water Pollutants, Chemical
7.
Am J Physiol Heart Circ Physiol ; 300(5): H1653-60, 2011 May.
Article in English | MEDLINE | ID: mdl-21357513

ABSTRACT

Surgical ventricular restoration (SVR) was designed to treat patients with aneurysms or large akinetic walls and dilated ventricles. Yet, crucial aspects essential to the efficacy of this procedure like optimal shape and size of the left ventricle (LV) are still debatable. The objective of this study is to quantify the efficacy of SVR based on LV regional shape in terms of curvedness, wall stress, and ventricular systolic function. A total of 40 patients underwent magnetic resonance imaging (MRI) before and after SVR. Both short-axis and long-axis MRI were used to reconstruct end-diastolic and end-systolic three-dimensional LV geometry. The regional shape in terms of surface curvedness, wall thickness, and wall stress indexes were determined for the entire LV. The infarct, border, and remote zones were defined in terms of end-diastolic wall thickness. The LV global systolic function in terms of global ejection fraction, the ratio between stroke work (SW) and end-diastolic volume (SW/EDV), the maximal rate of change of pressure-normalized stress (dσ*/dt(max)), and the regional function in terms of surface area change were examined. The LV end-diastolic and end-systolic volumes were significantly reduced, and global systolic function was improved in ejection fraction, SW/EDV, and dσ*/dt(max). In addition, the end-diastolic and end-systolic stresses in all zones were reduced. Although there was a slight increase in regional curvedness and surface area change in each zone, the change was not significant. Also, while SVR reduced LV wall stress with increased global LV systolic function, regional LV shape and function did not significantly improve.


Subject(s)
Cardiomyopathy, Dilated/pathology , Cardiomyopathy, Dilated/surgery , Heart Failure/pathology , Heart Failure/surgery , Heart Ventricles/pathology , Heart Ventricles/surgery , Aged , Aged, 80 and over , Cardiomyopathy, Dilated/physiopathology , Cardiovascular Surgical Procedures , Diastole/physiology , Female , Heart Failure/physiopathology , Heart Ventricles/physiopathology , Humans , Magnetic Resonance Imaging , Male , Middle Aged , Myocardial Contraction/physiology , Retrospective Studies , Stroke Volume/physiology , Systole/physiology , Treatment Outcome , Ventricular Remodeling/physiology
14.
Rev Esp Anestesiol Reanim ; 57(6): 341-50, 2010.
Article in Spanish | MEDLINE | ID: mdl-20645485

ABSTRACT

OBJECTIVES: To describe the health-care workload and instructional capacity of Spanish hospitals accredited to train anesthesiology residents. METHODS: Survey of supervisors of anesthesiology residents in 2008 to determine caseloads in surgery and obstetrics as well as in pain clinics and critical care units. The results are presented for different Spanish autonomous communities. The maximum theoretical capacity for instruction in accordance with European guidelines is calculated. RESULTS: The 100 hospitals surveyed train 325 residents per year and could theoretically increase the training opportunities they offer, within certain limits. Given optimal distribution of resources, the system could train 397 residents per year in pediatric surgery in 3-month rotations, 442 residents in neurosurgery in 2-month rotations, and 479 residents in thoracic surgery in 1-month rotations. Some Spanish communities presently have problems giving training in the settings of pediatric, thoracic, and major outpatient surgery. Furthermore, even though anesthesiologists are presently responsible for 41.6% of available critical care beds, 46 hospitals do not have a sufficient number of beds to give training in this setting. This shortage may have negative repercussions on the accreditation of training programs. CONCLUSIONS: Although certain limitations were found, the survey showed that the training capacity of the system is greater than accreditation suggests. It would therefore be possible to increase the number of residents.


Subject(s)
Anesthesiology/education , Hospitals/statistics & numerical data , Internship and Residency/statistics & numerical data , Workload , Accreditation/statistics & numerical data , Analgesia/statistics & numerical data , Analgesia, Obstetrical/statistics & numerical data , Anesthesia/statistics & numerical data , Anesthesia, Obstetrical/statistics & numerical data , Data Collection , Diagnosis-Related Groups , Female , Guidelines as Topic , Health Services Needs and Demand , Hospital Bed Capacity , Humans , Male , Obstetrics and Gynecology Department, Hospital/statistics & numerical data , Operating Rooms/statistics & numerical data , Pregnancy , Recovery Room/statistics & numerical data , Spain
15.
Transplant Proc ; 42(5): 1784-7, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20620523

ABSTRACT

BACKGROUND: Insufficient data exist on the clinical course of hepatitis C virus (HCV) infection in heart transplant (HT) recipients. Our study reports the outcomes of heart transplantation in pretransplantation HCV-positive (HCV+) recipients. METHODS: A retrospective analysis of the heart transplantation database at our institution was performed to identify HT recipients who were HCV+ prior to transplantation. Chart reviews yielded demographic features, liver function tests, graft function, incidence of posttransplantation acute hepatitis and transplant coronary artery disease, and patient survival data. RESULTS: Between 1995 and 2006, 10 HCV+ patients underwent cardiac transplantation. The recipient mean age was 47 years (range, 23-69). Seven recipients were males and 3 were females. At listing 9 patients had no cirrhosis. One patient with Child-B cirrhosis was listed for combined heart-liver transplantation. Two of 10 donors were known to be HCV carriers. Posttransplantation in-hospital survival rate was 100%. At a mean follow-up of 58 months (range, 1.6-145), 3 deaths occurred, yielding an overall survival rate of 70%. Only 1 death (10%) was linked to accelerated acute hepatitis. Transplant coronary artery disease was detected in 2 patients (20%). Echocardiograms of survivors at last follow-up revealed normal ejection fractions. In addition, there were no cases of hepatocellular carcinoma; all survivors were without evidence of hepatic dysfunction. CONCLUSIONS: Transplanting recipients known to have HCV did not seem to affect overall posttransplantation survival or to increase the risk of liver dysfunction or graft-related complications.


Subject(s)
Heart Transplantation/statistics & numerical data , Hepatitis C/complications , Adult , Aged , Echocardiography , Female , Graft Survival , Heart Transplantation/mortality , Heart-Assist Devices , Hepatitis C/epidemiology , Hepatitis C/mortality , Humans , Liver Cirrhosis/complications , Liver Function Tests , Male , Middle Aged , Retrospective Studies , Stroke Volume , Survival Rate
16.
Rev. esp. anestesiol. reanim ; 57(6): 341-350, jun.-jul. 2010. tab
Article in Spanish | IBECS | ID: ibc-79911

ABSTRACT

OBJETIVOS: Presentar la actividad asistencial y calcularla capacidad docente de los hospitales españoles acreditadospara la formación de residentes de Anestesiología.MÉTODOS: Encuesta a los tutores de residentes de loshospitales acreditados en 2008, recabando datos de actividadquirúrgica, obstétrica, dolor, procedimientos ydotación de camas de cuidados intensivos. Se describenlos resultados agrupados por comunidades autónomas yse calcula la capacidad docente máxima teórica según lasrecomendaciones europeas.RESULTADOS: Los 100 hospitales encuestados forman a325 residentes al año y podrían teóricamente ampliar suoferta docente, con ciertas limitaciones en las especialidadesde cirugía pediátrica, que con 3 meses de rotaciónsólo permite formar a 397 residentes al año con una distribuciónóptima de recursos; neurocirugía que con 2meses podría formar a 442 residentes y cirugía torácicacon 1 mes a 479 residentes. En la actualidad hay problemasen algunas comunidades autónomas sólo para anestesiaen cirugía pediátrica, cirugía torácica y cirugíamayor ambulatoria. En medicina de cuidados intensivos,aunque la especialidad de Anestesiología tiene 41,6% detodas las camas de críticos, preocupa la existencia de 46hospitales sin dotación adecuada. Este hecho influyenegativamente en la posible acreditación de unidadesdocentes.CONCLUSIONES: A pesar de las limitaciones encontradas,la encuesta muestra que la capacidad docente essuperior a la acreditada y por tanto sería posible aumentarel número de residentes(AU)


OBJECTIVES: To describe the health-care workloadand instructional capacity of Spanish hospitalsaccredited to train anesthesiology residents.METHODS: Survey of supervisors of anesthesiologyresidents in 2008 to determine caseloads in surgery andobstetrics as well as in pain clinics and critical careunits. The results are presented for different Spanishautonomous communities. The maximum theoreticalcapacity for instruction in accordance with Europeanguidelines is calculated.RESULTS: The 100 hospitals surveyed train 325residents per year and could theoretically increase thetraining opportunities they offer, within certain limits.Given optimal distribution of resources, the systemcould train 397 residents per year in pediatric surgery in3-month rotations, 442 residents in neurosurgery in 2-month rotations, and 479 residents in thoracic surgery in1-month rotations. Some Spanish communities presentlyhave problems giving training in the settings ofpediatric, thoracic, and major outpatient surgery.Furthermore, even though anesthesiologists arepresently responsible for 41.6% of available critical carebeds, 46 hospitals do not have a sufficient number ofbeds to give training in this setting. This shortage mayhave negative repercussions on the accreditation oftraining programs.CONCLUSIONS: Although certain limitations werefound, the survey showed that the training capacity ofthe system is greater than accreditation suggests. Itwould therefore be possible to increase the number ofresidents(AU)


Subject(s)
Humans , Male , Female , Internship and Residency/organization & administration , Anesthesiology/education , Anesthesiology/statistics & numerical data , Accreditation/standards , Hospital Accreditation , Hospital Accreditation , Hospitals, Teaching/standards , Hospitals, Teaching , Education, Medical, Continuing/methods , Education, Medical, Continuing/organization & administration , Anesthesiology/organization & administration , Anesthesiology/trends , Socioeconomic Survey , Faculty/organization & administration , Faculty, Medical/organization & administration , Faculty, Medical , Hospitals, Teaching/ethics , Hospitals, Teaching/organization & administration , Education, Medical, Continuing/standards
17.
Am J Physiol Heart Circ Physiol ; 298(1): H287-93, 2010 Jan.
Article in English | MEDLINE | ID: mdl-19855061

ABSTRACT

A safe, easy, and quick access into the pericardial space may provide a window for diagnostics and therapeutics to the heart. The objective of this study was to provide proof of concept for an engagement and access catheter that allows access to the pericardial space percutaneously. A multilumen catheter was developed to allow navigation and suction fixation to the right atrial appendage/wall in a normal swine model. Advancement through the multilumen catheter using a second catheter with a distal needle tip allows access to the pericardial space without pericardial puncture and advancement of a standard guide wire into the space. Navigation into the pericardial space was undertaken by fluoroscopy alone and was accomplished in 10 swine (5 acute and 5 chronic). As a specific application of this pericardial access method, a pacing lead was implanted on the epicardial surface. Five chronic swine experiments were conducted with successful pacing engagement verified by lead impedance and pacing threshold and sensing. Lead impedance exceeded 1,000 Omega preengagement and dropped by an average of 200 Omega upon implant (769 +/- 498 Omega). Pacing thresholds at 0.4 ms ranged from approximately 0.5 to 2.1 V acutely (1.03 +/- 0.92 V). No cardiac effusion or tamponade was observed in any of the acute or chronic studies. The ability to engage, maintain, and retract the right atrial appendage/wall and to engage an epicardial lead was successfully demonstrated. These findings support the feasibility of safe access into the pericardial space in a normal swine model and warrant further investigations for clinical translation.


Subject(s)
Cardiac Catheterization/methods , Electrodes, Implanted , Pericardium/physiology , Animals , Cardiac Pacing, Artificial , Catheterization , Electric Impedance , Electrocardiography , Feasibility Studies , Female , Fluoroscopy , Heart Ventricles , Male , Swine
18.
Rev Esp Anestesiol Reanim ; 56(8): 485-92, 2009 Oct.
Article in Spanish | MEDLINE | ID: mdl-19994617

ABSTRACT

OBJECTIVE: To determine the efficacy of recombinant activated factor VII (rFVIIa) to treat massive bleeding refractory to conventional treatment following cardiac surgery. PATIENTS AND METHODS: Retrospective study of 32 adults who underwent cardiac surgery and received rFVIIa to treat life-threatening postoperative bleeding after conventional means of correcting coagulopathy had failed. RESULTS: After administration of rFVIIa (90 microg x kg(-1), coagulation parameters soon became normal and blood loss decreased, with drainage going from a mean (SD) of 463 (321) mL in the hour when rFVIIa was infused to 155 (101) mL in the next hour (P < .001). Blood loss decreased by between 22% and 90% (mean, 66%), and the reduction was over 75% in 45% of the patients. Decreases in the transfusion of packed red blood cells (from 7A.4 [4.1] units to 2.7 [ 2.9] units; P < .001), plasma (from 4.7 [2.9] units to 1.6 [2.0] units; P < .001), and platelets were also noted. Mortality was 25%, although only 1 patient died from hemorrhagic shock. One patient developed thromboembolic complications (ischemic stroke). CONCLUSION: rFVIIa was effective in treating refractory bleeding after cardiac surgery, reducing blood loss and transfusion requirements and restoring blood parameters to normal.


Subject(s)
Cardiac Surgical Procedures/adverse effects , Factor VIIa/therapeutic use , Postoperative Hemorrhage/drug therapy , Postoperative Hemorrhage/etiology , Adult , Aged , Aged, 80 and over , Female , Humans , Male , Middle Aged , Recombinant Proteins/therapeutic use , Retrospective Studies , Severity of Illness Index
19.
Water Sci Technol ; 60(12): 3069-82, 2009.
Article in English | MEDLINE | ID: mdl-19955630

ABSTRACT

As part of the efforts done to introduce the practice of modeling in Latin America, this research carried out at the North-East WWTP of Monterrey represents the first comprehensive modeling case in Mexico. The main objective was to reproduce the organic carbon removal and sludge production rates of the plant, based on ASM1. Different intermediate studies were performed prior to the calibration of the model: influent characterization, tracer tests and hydraulics modeling, sludge settling tests and respirometry. Two fractionation methods (STOWA protocol and Influent-advisor) were compared, showing no equivalent patterns. A stepwise sequence of calibration was developed and successfully applied. The hydraulics of the reactors at the plant was reproduced by use of a series of 3 to 5 CSTRs. The waste and return activated sludge flowrates (Q(WAS) and Q(RAS)) were corrected based on the inorganic and total suspended solids mass balances. The Vesilind settling constants were measured (V(o) and r(hind)), while the flocculent zone settling parameter (r(floc)) was adjusted to calibrate the secondary clarifier. In ASM1, the adjusted parameters were the COD soluble inert fraction (frS(I)) and the particulate substrate fraction (FrX(S)). All other ASM1 parameters were kept at their default values. The steady-state calibrated model (in GPS-X) adequately described the quality of the effluent (carbon and nitrogen) as well as the sludge composition (M. Liquor and WAS). This case study provides voluntarily detailed data to allow its wide use for training and teaching purposes.


Subject(s)
Models, Theoretical , Organic Chemicals/analysis , Sewage/chemistry , Water Pollutants, Chemical/analysis , Water Purification/methods , Calibration , Chemical Phenomena , Mexico , Water Purification/instrumentation , Water Purification/standards
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