A considerable number of potential cDCD donors do not convert into actual organ donors because circulatory arrest does not occur within the predefined timeframe of warm ischemia after withdrawal of life-sustaining treatment. The main objective of this study is to determine parameters predicting time to death in potential cDCD patients.

Controlled donation after circulatory death (cDCD) is a major source of organs for transplantation. Even though there is a well-established cDCD program in the Netherlands, there is still a considerable number of potential donors not being converted into actual organ donors. A potential cDCD donor poses considerable challenges in terms of a) identification of those dying within the predefined timeframe of warm ischemia, after withdrawal of life-sustaining treatment to circulatory arrest, b) managing them appropriately within the framework and resources of the intensive care unit, c) dealing with family expectations especially when failure to donation occurs, and d) efficient utilization of the organ procurement teams.

Factors associated with early circulatory collapse after treatment withdrawal include a younger age, non-triggered modes of artificial ventilation, high FiO2, the use of inotropes, and a low arterial pH. Another important factor which could influence the donor potential is end-of-life treatment. The practice of withdrawal of life support treatment (WLST) is highly variable between ICU's and countries. This influences the dying process and can thus have a large influence on the onset of cardio respiratory arrest. There is also wide variation in the use and dosage of additional sedation and analgesia during WLST and controversy exists regarding hastening or slowing down death.

Several attempts have been made to develop models to predict the time between treatment withdrawal and circulatory arrest, as this is crucial to a) proceed with organ donation, and b) the quality of the harvested organs. The selected patients however, where not always restricted to potential candidates for cDCD organ donation as patients with cancer and severe infection were also included.

Objective: Objectives of this study are: a) To determine parameters predicting time to death in potential cDCD patients b) To validate and update previous predicting models on time to death after withdrawal of life-sustaining treatment. c) To assess variation in withdrawal of life-sustaining treatment in the Netherlands and its influence on post mortal organ donor potential and actual post mortal organ donors.

Design and setting: Multicenter, observational, prospective cohort study of all potential cDCD patients of 3 university and 3 teaching hospitals in the Netherlands with diverse focus of attention

Methods: All potential cDCD patients participating in the cDCD protocol as defined by the Dutch Transplant Foundation admitted at the Intensive Care unit, will be included.

Participants: Mechanically ventilated ICU patients aged between 18 to 75 years. Brain dead patients will be excluded.

Inclusion Criteria:

• mechanically ventilated patients
• aged between 18 and 75 years old, where further treatment is futile.
• patients should meet the criteria of potential cDCD donors as defined by the Dutch Transplant Foundation

Exclusion Criteria:

• non-intubated patients
• younger than 18 years old
• brain dead patients

All mechanically ventilated patients admitted at the Intensive Care Unit, aged between 18 and 75 years old who are eligible to enter the organ procurement protocol of the Dutch Transplant Foundation.