ABSTRACT
The limited number of organs and tissues available for transplantation in Venezuela and the need to improve outcomes for patients with life-threatening end-stage organ failure or inadequate quality of life resulted in the development and implementation of an organ and tissue procurement system by the Venezuelan National Transplant Organization. This procurement system, a 24-hour, nationwide, free phone service for detection of potential organ donors, connects callers with transplant coordinators. The on-call coordinator supervises family approach as well as maintenance, transport, and allocation of the organs and tissues. During a period of 21 months, the phone service received 1191 calls (713 requesting information to become a voluntary donor, 207 requesting information about donation and transplantation, and 271 reporting potential donors). Of the potential donors, 74% were men and 67% were aged between 11 and 40 years, and most came from hospital intensive care units, emergency departments, and trauma shock units. The main causes of death were trauma and stroke. Reasons why donation was not accomplished included early cardiorespiratory arrest and denied consent. In conclusion, establishing the procurement system resulted in an increase in the detection, referral, and maintenance of potential donors; doubling of the number of donors per million population; and an increase in the number of cadaveric transplants.
Subject(s)
Tissue and Organ Procurement/organization & administration , Adolescent , Adult , Child , Female , Humans , Male , Organizations , VenezuelaABSTRACT
BACKGROUND: Loss of bone mass after transplantation begins in the early periods after transplantations and may persist for several years, even in patients with normal renal function. While the pathogenesis of these abnormalities is still unclear, several studies suggest that preexisting bone disease, glucocorticoid therapy, and alterations in phosphate metabolism may play important roles. Recent studies indicate that osteoblast apoptosis and impaired osteoblastogenesis play important roles in the pathogenesis of glucocorticoid-induced osteoporosis. OBJECTIVES: To examine the early alterations in osteoblast number and surfaces during the period following renal transplantation. METHODS: Twenty patients with a mean age of 36.5 +/- 12 years were subjected to bone biopsy 22 to 160 days after renal transplantation. In 12 patients, a control biopsy was performed on the day of transplantation. Bone sections were evaluated by histomorphometric analysis and cell DNA fragmentation by the methods of terminal deoxynucleotidyl transferase-mediated uridine triphosphate nick end labeling (TUNEL), using immunoperoxidase and direct immunofluorescence techniques. RESULTS: The main alterations in posttransplant biopsies were a decrease in osteoid and osteoblast surfaces, adjusted bone formation rate, and prolonged mineralization lag time. Peritrabecular fibrosis was markedly decreased. None of the pretransplant biopsies revealed osteoblast apoptosis. In contrast, TUNEL-positive cells in the proximity of osteoid seams or in the medullary space were observed in nine posttransplant biopsies of which four had mixed bone disease, two had adynamic bone disease, one had osteomalacia, one had osteitis fibrosa, and one had mild hyperparathyroid bone disease. Osteoblast number in posttransplant biopsies with apoptosis was lower as compared with posttransplant biopsies without apoptosis. In addition, most of them showed a marked shift toward quiescence from the cuboidal morphology of active osteoblasts. Serum phosphorus levels were lower in patients showing osteoblast apoptosis and correlated positively with osteoblast number and negatively with the number of apoptotic osteoblasts. In addition, posttransplant osteoblast surface correlated positively with parathyroid hormone (PTH) levels and negatively with glucocorticoid cumulative dose. CONCLUSION: The data suggest that impaired osteoblastogenesis and early osteoblast apoptosis may play important roles in the pathogenesis of posttransplant osteoporosis. The possible mechanisms involved in the pathogenesis of theses alterations include posttransplant hypophosphatemia, the use of glucocorticoids, and the preexisting bone disease. PTH seems to have a protective effect by preserving osteoblast survival.
Subject(s)
Bone Remodeling , Chronic Kidney Disease-Mineral and Bone Disorder/etiology , Chronic Kidney Disease-Mineral and Bone Disorder/pathology , Kidney Transplantation , Adult , Apoptosis , Biopsy , Bone and Bones/pathology , Female , Glucocorticoids/therapeutic use , Graft Rejection/drug therapy , Humans , Male , Middle Aged , Osteoblasts/pathology , Parathyroid Hormone/blood , Phosphorus/blood , Postoperative ComplicationsABSTRACT
Donor shortage is the single most important limitation for allowing adequate growth of transplant programs. Transplant coordination programs have been shown to provide solutions to this situation worldwide. To evaluate the efficacy of transplant coordination programs in Venezuela, a pilot program was implemented at a 1200-bed teaching hospital. The implementation of this program included an assessment of the hospital's donation practices such as donor identification, maintenance, brain-death diagnosis, family consent for donation, and timely transport and allocation of organs and tissues. A follow-up 1 year after the implementation of the transplant coordination program demonstrated a 7-fold increase in the number of donors compared with the 2 previous years when the program did not exist. During the first year of application, the transplant coordination program resulted in solutions in how to address issues surrounding the procurement process in a hospital with a high potential donor rate; a linkage between the coordinator and the medical staff through educational activities; increased skills of hospital staff; and a methodology that should be applied extensively in hospitals with high donor potential to deal with the organ shortage.
Subject(s)
Personnel, Hospital/education , Tissue and Organ Procurement , Humans , Program Evaluation , VenezuelaABSTRACT
Se realizó un estudio controlado, prospectivo, a doble ciego y comparativo con placebo, en el cual se estudiaron 10 pacientes urémicos en hemodiálisis crónica que presentaban hiperpotasemia, con el fin de estudiar la eficacia de las drogas agonistas ß2 Fenoterol y Terbutalina en disminuir el potasio sérico cuando se administran por vía inhalatoria. Previamente a las hemodiálisis rutinaria programada de 3 semanas consecutivas, se procedió a la nebulización de 7,5 mg de Terbutalina, solución fisiológica como placebo y 7,5 mg Fenoterol. Se tomaron muestras de sangre de la fístula arterio-venosa a intervalos de 30 minutos hasta los 120 minutos y se realizaron las determinaciones de sodio, potasio, glicemia, calcio y gases arteriales. En esta investigación se evidenció qie el Fenoterol y la Terbutalina no produjeron un cambio significativo en los niveles de potasio sérico y la inhalación del placebo incrementó significativamente el potasio sérico con respecto a los valores basales, sin embargo, la administración de Fenoterol disminuyó discreta pero significativamente el potasio sérico a los 30 minutos de concluida la nebulización si lo comparamos con el comportamiento del placebo. Ambas drogas produjeron un aumento significativo de la frecuencia cardíaca y glicemia sin importancia clínica. No hubo cambios significativos en el resto de los parámetros médicos. Se registraron pocos y transitorios efectos colaterales. Se recomienda no utilizar, por ahora, la nebulización como vía de administración para suministrar los agonistas ß2 Terbutalina y Fenoterol con el fin de disminuir el potasio sérico en pacientes con insuficiencia renal crónica y ampliar los estudios dirigidos a evaluar terapéuticas de administración de estas drogas en pacientes con insuficiencia renal e hiperpotasémica
