Epidemias en la actualidad: de cómo los modelos matemáticos y estadísticos permiten entenderlas, aún a profesionales "adversos" a ellos / Mathematical models to understand pandemics

Since the declaration of SARS CoV-2 pandemic, we have witnessed an accelerated increase in new cases, frequently associated with the need for intensive care and mechanical ventilation. In parallel, we have been invaded by many experts in the press and who expose their knowledge on the behavior of epidemics who use concepts that are not always well understood by the medical community. Some concepts should be knowledgeable to understand the epidemic spread. First, the epidemic spread description is not modeled with an exponential curve, but rather with a Gompertz curve. Second, a gamma curve describes the period of contagiousness. Third, the contagion magnitude or rate can be calculated and modeled. Explaining these mathematical concepts in a simple and graphic way will allow readers to understand better what is happening with the current pandemic.

Análisis crítico de la baja tasa de donación de órganos en Chile / Critical analysis of the low organ donation rates in Chile

The highest organ donation rate in Chile was 10 donors per million population in 2017, which is low compared with other countries. Local experts attribute the low rate to population's lack of education and generosity, distrust in procurement/allocation system, inadequate legislation and insufficient encouraging campaigns, although without much empirical support: None of the countries from the OECD is also an organ donation leader. Latin Americans who migrate to Spain improve their donation rates, suggesting that the possible explanation is trust in the system where personalities do not have fast access to organs and common people do not have a sense of inaccessibility. Legislation changes in Chile did not have the expected results. Mega campaign did not reduce family refusal, but increased actual donors, probably due to health personnel sensitization. Real problems are inefficiencies in search and procurement processes, because procurement coordinators do not have enough time, dedication or priority to detect possible donors. Eighty seven percent of the latter are not notified to the procurement coordinator. Also, the services that care for possible donors are not adequately aligned. Procurement nurses do not have enough empathy or communication abilities and do not fulfil the professional profile required by the national coordination entity, which is unable to demand for results. The management of procurement coordinators should be improved, and their operational limitations should be visualized. Tools should be provided to the national agency in charge of organ procurement to have more political influence and credibility. Information technologies could ease warns, control and standardize, in real time, the procurement process.

Diseño de una propuesta de protocolo de estandarización y gestión de calidad para el proceso de procuramiento de órganos / Proposal of a management and standardization protocol for organ procurement in Chile

Background: Organ donation rates for transplantation are low in Chile and there is a paucity of a technical-structured-normalized procurement process. Aim: To design a protocol to standardize the organ procurement process based on the Chilean reality. Material and Methods: After a first phase of bibliographic reviews and analyzing de Chilean legislative and normative frame, a proposal was elaborated in collaboration with five expert coordinators. In the second phase, two Delphi rounds with the local coordinators of the organ procurement centers were carried out. Their responses were analyzed and the stages and criteria to standardize the organ procurement process were determined. Results: The expert defined organ procurement process, validated by local coordinators, comprised nine stages and 36 criteria. The expert opinion coincidence was high and significant (Cronbach's alpha > 0.8, p < 0.01). Conclusions: The protocol describing the procurement process, constructed and validated by experts, will allow to standardize a clinical protocol contributing to a successful national organ procurement.

El sinsabor que deja el mejor año en la donación de órganos para trasplante en Chile / Analysis of organ donation for transplantation in Chile during 2017

Background: In October 2016, television stations began a campaign to increase organ donation rates. During the months that followed, a sustained increase in donation rate was observed, reaching 10 per million people. Health authorities considered that this increase was a consequence of an improvement in the search and maintenance of potential donors and TV executives considered that is was due to a reduction in organ donation refusal by relatives of potential donors. Aim: To analyze the year after the TV campaign and determine its relative effect in the improvement of effective organ donation for transplantation. Material and Methods: Monthly figures of donors published on the websites of the National Transplant Corporation and the Ministry of Health and the historical figures for the 2013-2016 period were analyzed. Using this information, the expected behavior was modeled for the number of expected donors for the year 2017 and expected family refusal rates. Results: We found that the number of effective donors for 2017 did not differ substantially from the estimation and that the apparent substantial increase in the rate of organ donation was due to a marked but transitory reduction in the rate of donation refusal by relatives of potential donors. Conclusions: The whole process leading to effective donation should we reanalyzed. New strategies, such as information technologies should be incorporated to improve the detection and management of potential donors. The TV campaign, although successful, was very expensive and very difficult to sustain over time.