The introduction of MELD-based organ allocation impacts 3-month survival after liver transplantation by influencing pretransplant patient characteristics

Abstract

As there are insufficient organs to transplant everyone who might benefit from the procedure, rationing has to occur and the processes which will, in effect, result in the denial of a life-saving procedure for many individuals, need to be explicit, objective, just, equitable, transparent and retain public trust and confidence. Therefore, robust processes both for selection (determining who gets on to the transplant list) and allocation (who gets a donated liver) need to be developed and implemented. The principles of selection and allocation policies should be (and usually are) developed after full public consultation so that the various and often competing demands of equity, fairness, utility and benefit can be met as far as possible but the delivery of the principles will need to be implemented by clinicians. It is, of course, essential to define the purpose of the selection and allocation systems adopted and then audit the outcomes to ensure that the goals have been fulfilled, and identify any unintended consequences. In the UK, as in many other countries, for liver allograft recipients we have adopted what is primarily a utilitarian approach, listing when the survival probability is greater with transplant and there is a greater than 50% probability that the patient will be alive (with an acceptable quality of life) at 5 years [1]. Allocation is based on a national priority for super-urgent cases (such as those with fulminant liver failure) and thereafter allocated to the centre: we, as are some others, are exploring moving to an allocation system based on benefit. The USA has adopted an alternative approach, which has been widely used throughout the world [2]. After extensive research, discussion and consultation, in 2002 an allocation system was introduced with the primary aim of reducing the mortality of those on the transplant list. Within the defined geographical area, a donor organ is offered for an individual, in an order determined by the MELD score. There are literally hundreds of publications on the use of the MELD system and both its strengths and deficiencies are well recognized. The model has been well validated in many diseases and different health care systems: it is objective and not too susceptible to manipulation. However, technical, pharmacological, physiological and pathological factors may all affect the MELD score to give an inappropriate (high or low) survival probability and it may underestimate survival of those with hyponatraemia and ascites and, although there Correspondence James Neuberger, Organ Donation and Transplantation, NHS Blood and Transplant, Fox Den Road, Bristol, BS34 8RR, UK. Tel.: +44 121 627 2414; fax: +44 121 627 2449; e-mail: j.m.neuberger@bham.ac.uk