An ICU patient is suitable for consideration of donation after circulatory determination of death (DCDD).
a) Outline the process of determination of death in these patients. (30% marks)
b) Define the term ‘functional warm ischaemic time’ and discuss its significance to subsequent graft function. (40% marks)
c) Compare and contrast graft survival rates in recipients of kidney, liver, heart, and lung transplantation from DCDD and from donation after neurological determination of death. (30% marks)
This area of clinical practice is learned in mandatory CICM curriculum workshops, and therefore understanding of the process for determination of death in DCD patients should be well understood. The definition of functional warm ischemia time was incorrectly defined by most candidates, and knowledge of graft survival between different organs was also commonly incorrect.
The exam candidate, task-focused and stressed, will probably ignore the fact that this question would have worked just as well without the one-line clinical scenario posed in the stem. "An ICU patient is suitable for consideration of donation after circulatory determination of death (DCDD)" even omits "organ" from "donation", which is even more curious. Were we expected to hang our answer off this slender twig? Hard to say. What follows has not made any attempt to address any clinical scenario. Fortunately everything needed to answer this question is easily available from the ANZICS statement.
a) The process of determination of death:
The determination of death requires the patient to be:
After this point, death should be documented using a specific form.
b) Functional warm ischaemic time:
"The functional warm ischaemic time is the time from when the systolic blood pressure falls below 50 mmHg after withdrawal of cardiorespiratory support to cold perfusion and may be a better measure of ischaemic injury" (according to the latest ANZICS statement)
The effect of this time is to delay the recovery of graft function, or make donation impossible if the specific time for each organ is exceeded:
c) Graft survival: DCDD vs DNDD: