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Quantificazione e rappresentazione dell'equilibrio etico nel trapianto di fegato da cadavere e da vivente: verso processi di decisione clinica guidata da modelli matematici
Full text linkBackground. The decision process allocating a specific organ from a cadaveric or a living donor to a particular liver transplantation (LT) recipient is strongly influenced by ethical issues.
Aims. a) To effectively represent the potential equipoise achievable between the different ethical principles involved in LT. b) To construct a mathematical decision model able to objectify and quantify these ethical aspects.
Methods. The desirable LT ethical equipoise may be described by a triangle with the transplant benefit (life expectancy with LT minus that without LT) at its superior apex and, the potential harms to the waiting list and to the living donor at inferior apices.
We then constructed a Markov model to objectify and quantify the ethical equipoise triangle. The data sources to construct and validate the model were: the online UNOS web site, and a prospective database from Padua about a new allocation model.
Results. Our Centre was characterized by a significantly higher number of patients in the waiting list (150 vs. 58), organs/year (72 vs. 30) and proportions of patients with hepatic tumor (33% vs. 10%) with respect to the typical US centre. The annual dropout risk of patients with hepatic cancer, on the contrary, was significantly lower in our, than in the American centre (17% vs. 31%).
By using several simulations of ethically delicate clinical cases, our model showed that it is possible to objectify, measure, and modulate the clinical prognostic impact of the following ethical principles: the utilitarianism principles of benefit and of harm to the waiting list, the urgency and fair chances principles, the paternalistic and autonomy principles (living donor).
Conclusion. We constructed and validated the first prognostic decisional model based on both clinical and ethical variables able to influence the efficacy and safety of liver transplantation.Presupposti. Il processo decisionale che porta all'allocazione di un particolare organo da donatore cadavere o da donatore vivente ad uno specifico ricevente di trapianto di fegato è fortemente influenzato da problematiche etiche.
Scopo dello studio. a) Rappresentare in modo efficace il potenziale equilibrio realizzabile tra i diversi principi etici coinvolti nel trapianto di fegato b) Costruire un modello matematico decisionale in grado di oggettivare e quantificare questi elementi etici.
Metodi. L'equilibrio etico auspicabile nel trapianto di fegato può essere rappresentato attraverso un triangolo, al cui vertice superiore vi è il transplant benefit (spettanza di vita con il trapianto meno quella senza il trapianto) ed ai vertici inferiori il danno potenziale alla lista d'attesa ed al donatore vivente. Abbiamo quindi costruito un modello matematico di Markov per oggettivare e quantificare il triangolo dell'equilibrio etico. Le fonti dei dati per costruire e validare il modello sono state: il sito online UNOS, ed il database prospettico di Padova su un nuovo sistema di allocazione.
Risultati. Il nostro Centro si caratterizza per un numero significativamente maggiore di pazienti in lista d'attesa (150 vs. 58), di numero di organi/anno (72 vs. 30) e di proporzione di tumori epatici in lista (33% vs. 10%) rispetto al centro tipico degli USA. Il rischio annuo di dropout dalla lista nei pazienti con tumore è risultato invece significativamente minore nel nostro centro rispetto a quello americano (17% vs. 31%).
Utilizzando diversi possibili scenari clinici, il nostro modello ha dimostrato che è possibile oggettivare, misurare e modulare l'impatto clinico prognostico dei seguenti principi etici: principi utilitaristici del benefit e del danno alla lista, principio d'urgenza individuale, principio della prima chance, principio paternalistico (protezione del donatore vivente) e principio d'autonomia decisionale del donatore. Conclusione. Abbiamo costruito e validato il primo sistema prognostico - decisionale costituito da variabili sia cliniche che etiche in grado di influenzare l'efficacia del trapianto di fegato
Prognostic prediction and identification of candidates for salvage liver transplantation among patients with early hepatocellular carcinoma
No full textComment on
Risk factors for exceeding the Milan criteria after successful radiofrequency ablation in patients with early-stage hepatocellular carcinoma. [Liver Transpl. 2014
Methods and Statistical Analysis in a Study of Liver Resection vs Nonsurgical Treatments for Hepatocellular Carcinoma—Reply
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No full textWe read with great interest the comment letter by
Winter et al. on our recently published study on the
new concept of intention-to-treat (ITT) survival benefit
of liver transplantation (LT) in patients with hepatocellular
cancer (HCC).(1)Winter et al. reported some comments
mainly focused on the methodological approach
used for constructing the mathematical model.
We draw attention to the supplementary section of
our article in which we explain our approach.
We did not mean to imply that the construction of
our benefit model was innovative. Nor did we ignore
the seminal works of Merion and Schaubel, which we
referred to in our article. Rather, the innovation of our
work is connected with its ITT design
Personalized management of patients with very early hypovascular hepatocellular carcinoma
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Selection of patients with hepatocellular cancer. A difficult balancing between equity, utility, and benefit
No full textAlthough liver transplantation (LT) represents the gold-standard strategy for hepatocellular cancer (HCC), its use is circumscribed by several factors like donor shortage, perioperative complications, or competition with other candidates without HCC. Moreover, different alternative approaches like resection or loco-regional therapies may be attempted in selected cases. The best option for the treatment of an HCC patient is a complex decision, involving several ethical principles including: equity (horizontal equity and vertical equity or urgency), and utility. These principles influence the different phases of the patient selection process for LT: inscription in the waiting list (WL), deciding upon patient priority and drop-out before LT, allocating the liver donor to the best matched recipient. The best end-point for describing the principle of utility is the "transplant benefit" (TB). This concept expresses the survival gain obtained comparing LT with the best alternative therapies (i.e., difference between life years obtained with and without LT). The TB used with a mid-term time horizon (post-transplant 5-10 years), has the intrinsic potential to reach the dignity of an independent LT selection principle. Thus, the present review investigates the role of organ allocation using a TB model with the intent to introduce equity among patients transplanted having HCC or non-tumoral diseases
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
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