Non-heart-beating cadaver donors
Organ transplantation for end-stage disease is now well established worldwide in both developed and developing countries. Shortage of cadaver organs for transplantation remains a perennial problem, and is influenced by legal, ethical, cultural, and religious backgrounds of individual countries. The supply of organs from heart-beating brain-dead cadaver donors is inadequate to meet total demand. In developed countries the death rate from motor accidents has been lowered by public educational programmes, compulsory seat belt legislation, and other safety measures. Control of mortality from road crash epidemics has been an immensely impressive public health achievement; diminished numbers of brain-dead cadaver donors following road injury is an inevitable corollary.
Interest has thus rekindled in retrieval of organs from non-heart-beating cadavers. Organs from this source are unsuitable for liver, heart, or lung transplantation, but can be appropriate for kidney transplantation. Organ retrieval is facilitated by legislation governing early removal of organs after death, by public awareness of the problems, and by public support for organ transplantation. Kootstra and others in Europe and in the United States have shown that efficient organization in hospital emergency departments and in operating theatres can gain a significant number of adequately preserved kidneys from cadaver donors presenting with irreversible cardiac arrest. Special techniques include the insertion of aortic and caval balloon cannulae after groin cut-down, followed by rapid aortic delivery of large volumes of cold flushing solutions to provide in-situ cold perfusion of kidneys while preparations are being made for operative retrieval. Kidneys from these sources have provided very acceptable results; the frequency of delayed early function and of ultimately non-viable kidneys is higher than from heart-beating cadavers, but this additional source of cadaver organs has proved very valuable.
Extracorporeal storage
Simple cold storage
Most organs are subsequently immersed in cold preserving solution and stored at 0 to 4°C in a refrigerated container until reimplantation.
Kidneys are frequently transplanted within 24 h. This period can be extended safely for periods up to 36 to 48 h or longer, if such time is required to find and prepare an optimal recipient and to transport the refrigerated organ long distances. Liver and pancreas preservation with UW solution storage is effective for 12 to 24 h. Heart and heart–lung transplantation with current preservation solutions is restricted to a storage period of 5 to 6 increasing use of UW-derived solutions is likely to extend this time.
Perfusion storage
Organs are perfused continuously with a recirculating perfusate at 4 to 6. This technique is used less commonly now because of the increased effectiveness of preserving solutions for simple storage.
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