HealthTech draft guidance

Ex-situ machine perfusion devices preserve a donor liver outside of the body before it is transplanted. There are several ex-situ machine perfusion devices available. The precise configuration of each technology varies but they typically include a reservoir, a pump, an oxygenator, and a warming or cooling unit. The donor liver is placed into the device, which pumps a specially formulated solution through the organ's blood vessels. The circulating perfusion solution also clears, and prevents accumulation of, waste products. Machine perfusion is typically performed at hypothermic (4°C to 12°C) or normothermic (around 37°C) temperatures. A donor liver can be perfused for several hours (duration varies depending on the technology and perfusion method) before being implanted into the transplant recipient. The viability of the donor liver can be assessed during normothermic perfusion. Some devices can slowly rewarm livers from hypothermia to normothermia (termed 'controlled oxygenated rewarming') and some can provide a platform for liver splitting during machine perfusion.

Ex-situ machine perfusion devices may offer better organ preservation compared with static cold storage, with the aims of increasing the number of organs that can be transplanted and improving outcomes for transplant recipients. They can extend how long a donor organ can be preserved, which may allow more flexibility with logistics. Some devices also allow objective assessment of organ functionality, which may increase the number of available donor livers that can be safely transplanted.

Details of the 4 technologies included in this assessment are in table 1. Organ Care System (OCS) Liver was removed from the assessment after TransMedics advised that it would not be making the system available to the NHS for the use case outlined in the scope. As a result, the committee was unable to make recommendations on this technology.