DCD challenges SNOD course

DCD today DCD DONATION represents 40% of all transplants Increase complications due to increase in warm ischaemic time (WIT). 1% occurrence of ischaemic cholangiopathy with DBD liver. 28% occurrence of ischaemic cholangiopathy with DCD liver. Increase of primary non function x 2. Increase discard rate (27% DCD livers transplanted vs 83% DBD). Decrease in number of organs/donor: DCD:2.6 vs DBD:4) Increase in organ injury at time of retrieval (surgical haste in attempt to reduce WIT).

Organ utilisation from DCD donors

Aims Increase retrieval of organs Improve quality of organs retrieved DCD heart DCD lung Improve quality of organs retrieved Reduce WIT (withdrawal in anaesthetic room) Normothermic regional perfusion

DCD hearts Feb 2015 – April 2016 there have been 22 DCD heart retrievals and 20 successful transplants, from a small pool of donor hospitals within London, South East and Eastern area DCD heart retrieval and transplantation is safe in terms of patient outcomes.

DCD heart retrieval Papworth, Harefield and Wythenshawe Two models of procurement Direct (Papworth, Harefield and Wythenshawe) Normothermic regional perfusion (Papworth, only in three centres) Hearts re-started on OCS and transferred to implanting unit 30 transplants since February 2015 12 NRP (no deaths, but adverse impact on retrieval of other organs) 18 direct procurement (2 deaths) Business case being considered by Health Departments If we stick with hearts, let’s move onto DCD heart retrieval, which is now supported by three retrieval centres 2 methods of procurement OCS technology used to ‘revitalise’ heart for transport to implanting centre Excellent outcomes, although donors and recipients selected subgroups OCS technology expensive and business case being considered by DH

DCD Heart Retrieval: Sequence of events Papworth Hospital NHS Foundation Trust NHS DCD Heart Retrieval: Sequence of events sBP <50mmHg Circulatory Arrest Diagnosis of death WLS KTS FWIT 27 min. DPP 7 min. Heart reperfusion NRP 7 min. Time (min.) FWIT 18 min.

DCD heart retrieval The ask of us Agreement in principle Specifics Pre-withdrawal transthoracic echo Cross-match and albumin solution (to prime OCS circuit) Withdrawal in theatre / very close by What does it need from us. Minimise warm ischaemia. Most importantly, withdrawal in theatre or very close to it The heart in a box

DCD lung What is required for successful lung donation after circulatory death? Confirmation of Death Protection of the airway to prevent aspiration of stomach contents Early inflation of the lungs with oxygen

The confirmation of death after cardiorespiratory arrest Three vital caveats (from page 12) There will be no cardio-pulmonary resuscitation Five minutes is based on the evidence that after this time, spontaneous restoration of the heart and circulation will NOT occur. “It is obviously inappropriate to initiate any intervention that has the potential to restore cerebral perfusion after death has been confirmed Early inflation of the lungs with oxygen

Protection of the airway to prevent aspiration of stomach contents Lung DCD Confirmation of Death Protection of the airway to prevent aspiration of stomach contents Early inflation of the lungs with oxygen 2010

Lung DCD Confirmation of Death Protection of the airway to prevent aspiration of stomach contents Early inflation of the lungs with oxygen A cuffed breathing tube can be placed in the airway any time after death has been confirmed if necessary planned by someone appropriately experienced

Lung DCD Confirmation of Death Protection of the airway to prevent aspiration of stomach contents Early inflation of the lungs with oxygen Inflation of the lungs Minimum wait of 10 minutes after the onset of asystole Single recruitment maneuver Followed by CPAP 5cm H2O

Lung DCD

Optimisation of DCD liver retrieval Risk of adverse outcome compared with the DBD liver transplantation DCD overall ICU (WIT 26 min) OT (WIT 18 min) OR p P Graft survival 1.72 <0.001 1.98 0.02 1.65 0.006 Patient survival 1.36 0.01 2.15 1.20 0.29 Ischaemic cholangiopathy 16.48 19.68 <0.0001 13.73 Meta-analysis of DCD liver tx studies examining impact of location of WLST Overall DCD is associated with higher risk of death, graft failure and biliary complications when compared to DBD liver tx. However WLST in ICU lengthens WIT and this is associated with an even greater risk of these complications compared to WLST in OT.

Abdominal Normothermic Regional Perfusion (ANRP) WHAT IS NRP? Restores circulation of oxygenated blood to all abdominal organs. Implemented after circulatory arrest in DCD donors. Organ procurement then proceeds in similar manner to DBD donation

The descending aorta and supra-hepatic cava is cross clamped to ensure no return of circulation to the chest or brain. Establishing a localised, abdominal perfusion circuit

Uses extracorporeal membrane oxygenation (ECMO) technology. Keeps organs at normal temperatures (37°C). NRP lasts 2 hours.

Blood passes through organs continuously Cells are fully nourished with oxygen and nutrients until organ preservation with cold UW Cellular ATP is at normal levels WHAT we achieve? IF CELLS RUN OUT OF ATP They BURST. Before this happens calcium builds up in the mitochondria Mitochondria are damaged Cells look OK but they will not recover- Primary Non Function DCD DONATION represents 40% of all transplants Increase complications due to increase in warm ischaemic time (WIT). 1% occurrence of ischaemic cholangiopathy with DBD liver. 28% occurrence of ischaemic cholangiopathy with DCD liver. Increase of primary non function x 2. Increase discard rate (27% DCD livers transplanted V 83% DBD). Decrease in number of organs/donor. ( National Ave: DCD/2.6 V DBD/4). Increase in organ injury at time of retrieval (surgical haste in attempt to reduce WIT). Cells take in water and sodium all the time- They pump it out all the time 90% of ATP is used to keep the cell water balance constant

WHAT HAPPENS IN CELLS DURING DBD ORGAN RETRIEVAL? ATP is continuously produced is continuously consumed Chilling the cells with UW Stops making ATP Keeps consuming ATP but at a slower rate Late onset of cell death

WHAT HAPPENS IN CELLS DURING DCD ORGAN RETRIEVAL? Loss of circulation causes ATP to fall rapidly. Cold perfusion slows ATP loss ATP levels fall to lethal levels sooner in DCD

WHAT HAPPENS IN CELLS DURING NRP?

BENEFITS OF NRP Replenishes the ATP reserves. Potentially can reduce ischaemic (reperfusion) injury. Allows for macroscopic assessment - Appearance - Bile duct blood flow - Portal Vein/Hepatic Artery flows - Small bowel appearance Enables a dynamic assessment of organ quality (using biochemical and blood gas analysis). Less hasty retrieval-converts DCD to DBD type retrieval reducing the incidence of organ injury. Gradual expansion of organ acceptance criteria.

SO WHAT DO I NEED TO KNOW? Are they planning on retrieving using NRP? Do they have a machine perfusionist – what will be expected of you? How many units of blood will this require? Are they bringing a portable blood analyser? How long will this likely extend the theatre time by?

SNODs will not be required to carry out any tasks involved in actual NRP sampling. The NORS team bring the NRP bags and will take the samples. If the SNOD is attending an NRP and QUOD proceeding donor the SNODs role in facillitating QUOD does not change. The QUOD box is handed over to the NORS team in theatre as per SOP4044.

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