Potential for organ donation in the United Kingdom: audit of intensive care records

Introduction

The United Kingdom has a serious shortage of organs for transplantation, as does almost every country. The number of patients waiting for a kidney transplant has increased from 3954 at the end of 1994 to 5736 in 2005 and continues to rise by around 1.5% a year. In 2005, there were 1312 kidney transplants from 715 dead donors and 538 transplants from living donors. Waiting lists for liver and cardiothoracic organ transplants are artificially low as access is restricted to approximate the anticipated number of organs available for transplantation. At the end of 2005, 360 patients were registered for a liver transplant and 394 for a cardiothoracic transplant, and in that year there were 605 liver and 286 cardiothoracic transplants. Nevertheless, 6-11% of patients accepted for these lists die before an organ becomes available and a further 2-8% are removed from the list because their condition deteriorates and transplantation is no longer appropriate. The number of deceased heartbeating donors has remained relatively static since 1998, ranging from 644 to 739 donors a year, having fallen from a peak of 923 in 1989.1 2 The heartbeating donor rate in 2004 was 12.3 per million population, which is one of the lowest rates in western Europe. Spain has an exceptional rate of 33.0 per million population, but many other countries in Europe have rates between 13 and 22 per million population (table 1).3

Several transplant and coordinator teams in the UK have carried out local surveys into the potential for organ donation from intensive care units, but only one systematic study has ben performed, which was carried out in 1989-90 and was restricted to England and Wales.4 5 This estimated that in 1200-1350 patients a year death was diagnosed after brain stem tests and that half of these patients became actual organ donors. It also reported that, when approached, 30% of relatives of potential donors refused consent for organ donation, though differences in methods prevent direct comparisons with our study.

UK Transplant, now a division of NHS Blood and Transplant, was established in 2000 with a specific responsibility to introduce measures to increase organ donation. As part of this process a national potential donor audit was developed to identify the true potential for organ donation from dead donors, together with the reasons for non-donation.6 These data will identify where in the process, and for what reason, potential donors fail to become actual donors. This allows focused initiatives to be introduced to address shortcomings of the system in a specific way. We describe the establishment and implementation of the potential donor audit together with the overall results from the first two years for potential heartbeating donors.

Methods

The potential donor audit was designed on a hierarchical basis. Basic demographic information (not patient identifiable) is obtained for all patients who die in an intensive care unit, together with date, time, and cause of death. This is followed by questions concerning whether or not death was diagnosed by brain stem testing, whether or not solid organ donation was considered, the process by which relatives were approached, and whether or not consent was obtained. Finally, information is requested on whether or not organs were offered for transplantation and whether or not organ donation occurred.

After an extensive pilot study, the final version of the audit form was developed (see bmj.com). Data are collected by donor transplant coordinators, donor liaison nurses, and some intensive care unit link nurses. All forms are submitted to UK Transplant for data entry and validation checks, with any queries being resolved whenever possible with the person who completed the form. Strenuous efforts are made to ensure that the study includes all intensive care units in the UK with the potential for providing deceased heartbeating solid organ donors and that forms for all deaths are completed. This includes regular comparisons between the actual numbers of deaths and the number of forms received.

Fully validated data on deaths in intensive care units are available from 1 April 2003. In the first two years of the audit, up to March 2005, data were obtained on 46 801 deaths in 341 intensive care units in 284 different hospitals.

Results

The figure shows a schematic breakdown of the 46 801 audited deaths. In summary, 91% of the patients were being mechanically ventilated at some point during their stay in the intensive care unit. Of those, 2740 (6%) were potential heartbeating donors in that death was diagnosed by brain stem testing and there were no absolute medical contraindications to heartbeating solid organ donation. For 420 (15%) of the families of the 2740 potential donors there was no record of discussion or approach regarding organ donation with the next of kin. Reasons given for the lack of discussion include the patient's general medical condition or the next of kin stating that they would not give permission before being asked. Of the 2320 families who were approached or initiated an approach, 59% gave consent for heartbeating organ donation, and 1244 (90%) of the 1379 patients became organ donors. Around 41% of families denied consent (95% confidence interval 38.6% to 42.6%). We refer to this as the refusal rate.

A breakdown of the 46 801 audited deaths (*either known or suspected variant Creutzfeldt-Jakob disease or known HIV infection; †includes cases where the next of kin made the approach)

Table 2 shows the main reasons given for relatives' lack of consent. Individuals may have given more than one reason. No single reason was given much more commonly than the others. Other reasons for refusal were given by 244 families (26%) and included “the family wanted to be with the patient when the ventilator was turned off,” “religious beliefs,” and “the family do not agree with organ donation.”

Table 3 shows the refusal rate by sex, age group, and ethnicity. Information on sex, age, and ethnicity was not available for all 2320 potential donors, and so the table gives the numbers in each group on which the refusal rate is based. The refusal rates for males and females and the six age groups did not differ significantly. There is strong evidence of a difference in white and non-white potential donors based on the 2174 potential heartbeating donors whose ethnicity was recorded, the refusal rate for whites being 35% (33% to 37%), while that for the group of ethnic minorities is 70% (63% to 77%). More detailed analyses using logistic regression modelling confirmed these results.

Discussion

The national potential donor audit is the first comprehensive, UK-wide study to try to identify the number of patients dying in intensive care units who could donate their organs for transplantation. It does so by recording information on every patient who dies in intensive care in the UK, which gives a more accurate picture than can be obtained from extrapolations derived from local studies. While it would be ideal to collect all data contemporaneously, the practicalities of the process mean that data have been collected within two to four weeks of each death. This does not seem to have resulted in missing data, which is a tribute to the assiduity of the donor coordinators and their colleagues who have collected the data. It is also important to note that data collection has taken place with the agreement and full cooperation of intensive care units but has not relied solely on the staff for data collection.