Donation after cardiocirculatory death in Canada

Key considerations

• A “consensual decision to withdraw life-sustaining therapies” is defined as a decision that has been agreed to by the patient, family and the treating health care team.

• DCD replaces but is synonymous with other terms such as NHB donation, donation after cardiocirculatory determination of death or donation after cardiac death.

• This forum has used the terms “uncontrolled” (regardless of location, cardiac arrest is unanticipated) and “controlled” (cardiac arrest is anticipated). These terms replace existing categorizations that include the Maastricht criteria.6

• The terms “controlled” and “uncontrolled” should not be misunderstood to imply a reflection on professional behaviour or the organization of clinical services. The degree of control refers to the temporal constraints and the opportunity for consent discussions in relation to death.

• For uncontrolled DCD, management is complicated by the fact that death is sudden or unanticipated and may not have occurred within the medical setting. Although donation interventions should be initiated as soon as possible, the surrogate decision-makers or advance directives may not be immediately available to provide consent.

• For controlled DCD, life-sustaining therapy can be defined as ventilatory support, artificial airway support, hemodynamic support or a combination of these provided in the ICU or special care unit. Patient conditions may include, but are not limited to, severe brain injury of diverse etiology, end-stage neuromuscular failure, high cervical spinal cord injury and end-stage organ failure.

• For completeness, the forum addressed both forms of DCD. However, in its conclusion, the forum has recommended that programs initiate and establish controlled DCD before advancing with uncontrolled DCD (recommendation 9.2).

Summaries of evidence

Key considerations

• For the purposes of DCD, 1 of the physicians determining death must be a staff physician with full and current licensure for independent medical practice in the relevant Canadian jurisdiction. Physicians on an educational register (residents, fellows) may carry out the second determination.

• The legal time of death is the determination after a 5-minute observation period.

• The purpose of the 5-minute observation period is to confirm the irreversibility of cardiocirculatory arrest before organ procurement.

• Blood pressure is defined as an arterial pressure that generates anterograde circulation. The preferred method to confirm the absence of blood pressure is by arterial line monitoring.

Summaries of evidence

3.1 Process and procedures for WLST

Decision-making process for WLST

a) The medical and ethical framework for WLST in the ICU falls within the domain of critical care and neurocritical care practice and must not be influenced by donation potential. It is the responsibility of the critical care and neurocritical care communities to ensure optimal and safe practice in this field.

b) Health care professionals responsible for the decision and procedure to withdraw life-sustaining therapies should

• Have the requisite skill and knowledge in the area

• Not have any association with the proposed transplant recipient that might influence judgement

• Be independent of transplant proceedings and

• Act in accordance with current end-of-life practice in the local ICU or special care unit.

c) The decision to withdraw life-sustaining therapies should be made before any discussion of organ and tissue donation that is initiated by health care providers. The organ donation/procurement/transplant team must not be involved in the decision to withdraw life-sustaining therapies.

Procedures for WLST

a) The management of the dying process, including procedures for WLST and sedation, analgesia and comfort care, should proceed according to existing ICU practice in the best interests of the dying patient and should not be influenced by donation potential.

b) Consideration for the dignity of the dying process should be guided by patient interests and the family's needs and desires.

c) The family should be provided with a clear explanation of their option to remain with the patient during WLST, at the time of death and beyond, and there should be a full discussion of the variables that may affect organ viability for successful donation.

d) The ICU patient care team is responsible for all aspects of management during this interval of care leading to death. The organ donation/procurement/transplant team must not be involved in WLST procedures or in the management of the dying process.

e) WLST is an accepted part of end-of-life care in most hospitals in Canada and proceeds in accordance with accepted medical and ICU practice. We recommend that ICUs establish policies and procedures that

• Are consistent with current practices and

• Apply to all patients where WLST is considered.

These policies and procedures should be locally determined and may include a bioethics consultation or opinion by a second physician.

Key considerations

• The quality of the decision-making process must not be influenced by the potential for DCD.

• When WLST is proposed and DCD may be considered, the decision to proceed with WLST should be inclusive, consultative, contemplative and appropriately timed.

• As it applies to palliative care, the principle of double effect supports the administration of treatments with the intent to support patient comfort and alleviate suffering, even if there is a risk (foreseen but not intended) of hastening death.22

3.2 WLST requirements and safeguards

For the purposes of DCD, we recommend that the following additional requirements or safeguards be in place regarding the WLST decision-making process and procedures:

• Established ICU or hospital policies and guidelines related to WLST, including bioethics input

• Review of DCD case management and a periodic quality assurance process

• Planned staff debriefing on a regular basis.

Key considerations

• Quality of patient care and decision-making should be the same irrespective of whether donation is considered. Policies and procedures for WLST should be in place for both donation and non-donation cases.

• Support for health care professionals should be provided as required.

3.3 Donor and recipient care

In the ICUs of hospitals that perform transplants, there may be unavoidable times when a potential controlled DCD donor (before death) is cared for in the same unit as an end-stage organ failure patient who is a potential transplant recipient. Under these circumstances, we recommend that attending hospital staff caring for the recipient should be different from staff caring for the donor.

Key considerations

• “Attending staff” is defined as the attending staff physician and bedside nursing staff.

• It is recognized that local realities regarding logistics, staffing and practicalities may make it difficult to follow this recommendation. However, hospitals or jurisdictions implementing DCD programs should be responsible for providing the support necessary to develop this capacity.

3.4 Maximum time limit from WLST to death

We recommend that there be a maximum time limit from WLST to death beyond which organs will not be offered or procured; that is, if death does not occur within this period, organs will not be procured and ICU end-of-life care will continue.

This time limit should be 1 to 2 h, but should be guided by individual organ-specific programs and individual donor factors.

Key considerations

• Time limits are related to family factors and ICU and operating room logistics.

• Setting time limits helps clarify expectations for families and staff.

• Time limits are congruent with organ viability limits in section 7 of these recommendations.

3.5 Estimation of time to death after WLST

We recommend that following consent specific to this procedure, a formal estimation of the time to death after WLST be made using tools such as, but not restricted to, the Wisconsin evaluation tool.23 The tool may be used to:

• Determine eligibility to donate

• Provide input to family discussions about likelihood for successful donation

• Guide the preferred location for WLST.

Key considerations

• Tools to estimate time of death after WLST are not currently used as a standard practice in the ICU. They should be considered as a donor-based intervention and appropriate consent should be sought.

• The safety of the procedure should be considered before its application.

• The reliability of predictive tools depends on patient conditions and the specific ICU actions and tempo of procedures during WLST.

• These tools are in evolution and should be adjusted based on continuing research.

• Some clinical conditions, such as patients on extracorporeal life support, including artificial heart technology, or previous documentation of apnea (for other indications), do not require predictive testing.

3.6 Location of WLST

We recommend that WLST should occur in the ICU or in the operating room, with flexibility based on family preferences, institutional logistics, resources and facilities.

Key considerations

• The family should be given information about the impact of the location of WLST on the potential for successful donation.

• Psychosocial, spiritual and bereavement support should continue to be provided to families regardless of the location of WLST.

3.7 Transfer of patients before WLST

We recommend that a patient who fulfills eligibility criteria for controlled donation, at a hospital where DCD is not practised or available, may be transferred before WLST to a hospital that performs controlled DCD. This should only occur with the full informed consent of the patient or family and with full consultation with and the agreement of the receiving hospital.

Key considerations

• This recommendation is based on the principle of referring a patient to a hospital that provides a service not available at the source hospital and is specific to donation/procurement hospitals that provide DCD.

• Logistics and funding to support this activity should be provided by individual jurisdictions.

• Costs associated with transfers should not impose an economic burden on the family.

• The family should be aware that imminent death following WLST and organ donation may not occur despite the transfer.

Summaries of evidence

4.1 Option of organ and tissue donation

We recommend that:

a) The option of organ and tissue donation should be routinely provided to all potential donors and families. Distinct from common practice after NDD, it is necessary to present the option of donation before the fact of death in controlled DCD.

b) In centres that develop DCD programs, the option of organ and tissue donation should be presented to patients and families after the consensual decision to withdraw life-sustaining therapies but before the act of withdrawing life-sustaining therapies. A discussion of donation options may occur at any time if initiated by a patient or family request for information.

c) The person or group who is best trained and most experienced should hold the consent discussions, based on local organizational or institutional practice.

Key considerations

• A “consensual decision to withdraw life-sustaining therapies” is defined as a decision that has been agreed to by the patient or family and the treating health care team.

• The initial discussion about the possibility of donation should be distinguished from the discussion to obtain informed consent for donation.

4.2 Notification of coordinators

For controlled DCD where the patient fulfills eligibility criteria for donation, it is necessary to involve a separate coordinator before death. We recommend that coordinators be routinely notified by the ICU team after the consensual decision to withdraw life-sustaining therapies but before the act of WLST.

Key consideration

This recommendation should be considered in the context of provincial legislation.

Summaries of evidence

In controlled DCD, a competent patient or his or her surrogate has consented to the withdrawal of ventilation or other life-sustaining therapy. Consent implies that the patient or substitute decision-maker has been informed of the nature and purpose of the treatment withdrawal and understands what this action entails. Consent to organ procurement for transplantation is given by a patient or surrogate independently of consent to withdraw life support and presumes that procurement will take place only after death has been declared. Life support can justifiably be withdrawn and organ procurement commenced after a clinical declaration of death.36 Withdrawal of life support and subsequent organ procurement are permissible provided that the patient has been deemed imminently and irreversibly dying and has consented separately to the withdrawal of life support and to organ procurement for transplantation.37

5.1 Donation-based interventions

We recommend the following:

a) Before death (as defined in recommendation 2a), and as it applies to controlled DCD, the care of the patient is under the direction of the patient care team. Interventions to facilitate donation require the specific and informed consent of the patient or family for each intervention. Their purpose should be understood in terms of how they might improve successful donation after death. These interventions should not be intended to hasten death or otherwise harm the patient and should pose no more than minimal risk. Interventions should only be undertaken with consideration of risks and benefits.

b) After death (as defined in recommendation 2a), and as it applies to controlled and uncontrolled DCD, interventions require only general consent to donation.

c) Surgical interventions related to cannulation and perfusion should be carried out only by the organ retrieval or transplant team.

d) Thrombolytic agents should not be administered before the fact of death.

e) Heparin should not be administered before death in cases of established or ongoing bleeding.

f) Vasodilators should not be administered before death in patients who are receiving vasopressor support.

g) Interventions that may re-institute cerebral perfusion and oxygenation after the fact of death should not be performed.

Key considerations

• Benefit to the patient is interpreted as both therapeutic benefit to the patient and realization of the donor's interests and wishes based on the desire and intent to donate.

• Where the medical team seeks consent for pre-or post-mortem interventions, the team must ensure that the proxy has appropriate (legal) authority to grant such consent. Consideration should be given to the legal authority granted by consent to treatment legislation, tissue and organ donation legislation, and case law.

• DCD has not been directly addressed in existing law. The consent regime as it applies to DCD, especially related to pre-mortem interventions, must be examined on a jurisdiction-by-jurisdiction basis to identify gaps or ambiguities.

• When the patient is capable, informed patient consent is to be obtained.

5.2 Responsibility for pharmacologic interventions before death

We recommend that the ICU team or the anesthesiologist caring for the potential donor in the operating room be permitted to administer pharmacologic donor-based interventions before death.

Key considerations

• Organ donation or transplant coordinators who are not part of the patient care team should not administer donor-based pharmacologic interventions.

• ICU team members should use their professional discretion in carrying out such treatments. This recommendation does not obligate ICU team members to carry out treatments they consider against the best interests of the patient.

Summaries of evidence

The doctrine of double effect,22 which acknowledges that the same act can have both good and bad effects, consists of 4 conditions:

1. The action must be intrinsically good, independent of its consequences.

2. Although the bad effect of the action can be foreseen, the agent must directly intend only the good effect.

3. The bad effect must not be a means to the good effect.

4. The good effect must be proportional to, compensate for or outweigh the bad effect.

In many DCD programs, it is permissible to perform interventions on the patient to preserve the option of donation for the family, maximize the potential for useable organs or improve the function of organs once transplanted. If the intention is not to hasten the death of the donor but to preserve the organs to provide benefit to the recipient, then the doctrine of double effect can potentially apply.14

These interventions may include:

• Blood testing and relevant investigations for donor eligibility (ABO type, HLA-typing, virology screen, organ function evaluations)

• Preparation for vessel cannulation

• Isolation or exposure of vessels for cannulation

• Vessel cannulation for in-situ perfusion

• Administration of anticoagulants (heparin)

• Administration of vasodilators (phentolamine)

• Administration of thrombolytic agents (streptokinase)

• Extracorporeal oxygenation and circulation

• In-situ perfusion with cold preservation solution.

In controlled DCD (depending on the intervention), these interventions may occur:

• Before WLST

• After WLST, but before death

• In the interval between the onset of cardiocirculatory arrest and the formal determination of death

• After the determination of death.

When discussing whether these interventions are permissible, it is important to consider:

• Evaluation of benefit, i.e., does it contribute to successful donation?

• Evaluation of foreseeable harm or risk:

- Interventions that do not involve greater than minimal harm or risk and thus do not require detailed consent

- Interventions that involve a minor increase over minimal harm or risk and thus require detailed consent

- Interventions that involve a significant increase over minimal harm or risk and thus should not be offered.

6.1 Consent process

We recommend that:

a) The option of organ and tissue donation should be routinely provided after death in uncontrolled DCD to the families of potential donors.

b) The consent process (which should include acknowledgement of expressed donor intent, the identification of appropriate legal surrogate or the consent or refusal of donation) should be dictated by provincial legislation and current medical and ethical practice.

c) Expressed donor intent is legally sufficient to proceed with donation in the absence of proxy consent. However, it is recognized that the psychosocial, emotional and spiritual meaning of the act of donation will influence the decision-making process with families, even in the presence of a signed donor card or other indication of intent to donate.

d) In the absence of expressed donor intent and family consent, interventions and procedures for donation should not proceed.

e) Given its complexity, the consent process should be led by the most experienced person who can obtain the requisite informed consent and who is not part of the transplant team.

Key consideration

Expressed donor intent is considered legally to be a valid form of consent and is defined as a signed donor card or donor registry in the absence of any reason to believe the consent has been withdrawn. It is acknowledged that ethical or moral considerations may override the authority that the legal regime bestows.

Summaries of evidence

For uncontrolled DCD, the deceased has had a witnessed cardiocirculatory arrest of known duration and there should already be an established decision to terminate or not to initiate CPR. Management of uncontrolled DCD is complicated in that death is unanticipated and medical teams are unprepared for commencement of in-situ preservation. When death is sudden or unexpected, the relatives of the deceased or surrogate decision-makers are often not present and advance directives may not be immediately available. In North America, ideally informed consent before donation-based interventions should be sought. However, the wishes of the deceased may or may not be known and next of kin may be absent. Some jurisdictions, including some American states, have adopted laws that allow for in-situ preservation without consent (District of Columbia DC ST 2002; Florida Statutes 2002; Virginia State Code 2002). There are time constraints on these interventions, and it is possible that consent may not be available in a time frame that allows organ procurement. Despite legalization of these interventions, serious ethical questions regarding the appropriate conduct of physicians at the time of death remain an issue. Possible interventions include:

• Blood testing for donor eligibility (tissue typing, cross match, virology screen)

• Vessel cannulation

• In-situ perfusion

• Administration of anticoagulants

• Administration of vasodilators (phentolamine)

• Administration of thrombolytic agents (streptokinase)

• Re-institution of chest compression, mechanical ventilation

• Extracorporeal circulation and oxygenation

There are 2 schools of thought on the issue of in-situ preservation without prior consent. Minimization of warm ischemic time (WIT) preserves post-transplant organ function and provides the family with an opportunity to consider the merits of organ donation in a less hurried and somewhat less stressful environment. Given more time to consider the option, family support for DCD has been shown to dramatically increase if cannula insertion occurs before, rather than after, family consent.40 Nonetheless, ethical questions may arise when medical interventions are performed in the absence of prior informed consent from the deceased or the family. Public surveys in the United States have shown that 74% of respondents opposed allowing physicians to proceed with intravascular cannulation without prior consent.41 Many authors do not support these interventions, arguing that dignity of the dead is undermined by the unilateral decision of medical caregivers to proceed with these interventions.

In some uncontrolled DCD programs, it is permissible to perform interventions on the deceased to preserve the option of donation for the family, to maximize the availability of useable organs and improve the function of transplanted organs. To achieve these goals, the interventions may need to be started before family consent is given.

When discussing whether these interventions are permissible, it is important to consider the ethical justifications for intervening with a dead body to preserve options of the family for donation, respect for the body, principles of consent and the legal implications.

7.1 Warm ischemic time (WIT)

We recommend that WIT be defined as:

• Initiation of WLST to cold perfusion in controlled DCD

• Cardiac arrest to cold perfusion in uncontrolled DCD.

Independent of definition and limits of WIT, we recommend that the following data and times be recorded for transplant purposes:

Controlled DCD

• The first action in WLST (e.g., weaning inspired oxygen)

• The final action in WLST (e.g., extubation)

• Urine output during WLST

• First fall in systolic blood pressure below 50% of baseline

• First fall in oxygen saturation below 80%

• Onset of circulatory arrest

• The 5-minute interval

• Determination of death (physician 1 and physician 2)

• Initiation of cannulation (femoral or sternolaparotomy)

• Initiation of cold perfusion of organs

Uncontrolled DCD

• Time from cardiac arrest to initiation of CPR

• Duration of CPR before death determination

• Determination of death (physician 1 and physician 2)

• Initiation of cold perfusion of organs

Key considerations

• The process of WLST varies among hospitals and ICU practitioners; the terminal events in the process of dying also vary among individual patients.

• Documentation of physiologic events during WLST is important when organs may be used for transplantation.

7.2 Maximum time for offering organs

We recommend that the maximum time beyond which organs should not be offered for controlled or uncontrolled DCD be determined by local transplant program protocol and experience.

Key considerations

• According to current practice, the maximum time for offering organs is approximately 2 h (2 h for kidneys, 1 h for pancreas and lungs, 30 minutes for liver).

• Other variables important in the time limit include (but are not limited to) age and comorbidity of the donor and agonal events during WLST.

Summaries of evidence

Ischemic organ injury has a direct impact on organ viability for transplantation and is a limiting factor in organ recovery for DCD. This organ injury can be delayed by the use of hypothermia and preservation solutions. Definitions of WIT in controlled DCD vary in the literature (Table 5); WIT has been defined as:

• The time from cardiocirculatory arrest to cold perfusion of the organs

• The time until a fall in physiologic parameters (blood pressure and oxygenation) below a predetermined level to cold perfusion of the organs or

• The time from WLST to cold perfusion.

Although there is general agreement that WIT should be minimized, various allowable time limits for WIT related to kidney transplantation have been recommended, most ranging from 30 to 45 minutes.42^–44 However, longer WITs have resulted in satisfactory functional graft recovery in animal models for NHB kidney transplantation.45 This suggests that setting an absolute threshold for WIT is difficult. In clinical practice, other parameters such as the age and general health of a prospective NHB donor and the temporal progression of organ ischemia during the dying process are relevant.

Not all transplant teams share the opinion that WIT is of primary importance. Alonso and colleagues46 argued that a still-to-be-defined allowable period of warm ischemia does not alter outcomes in NHB renal grafting. Although they reported significantly increased rates of delayed graft functioning in their NHB donor kidneys where WIT > 2 h, 3-month recovery rates were no different. It seems inherently logical that the duration of warm ischemia is directly related to long-term transplant viability, but no evidence for this supposition could be identified during our review.

Among organs that may be transplanted, the lung is unique in its ability to withstand warm ischemia. Because of its histologic structure, consisting primarily of elastic tissue, the lung has minimal metabolic requirements. Furthermore, the alveolocapillary membrane of the lung can meet its requirements for oxygen through direct diffusion. Potential controlled NHB lung donors would be intubated and typically ventilated with oxygen, thereby maintaining the saturation of intrapulmonary blood. Furthermore, the pulmonary endothelium is also capable of functioning for several hours following circulatory arrest. For reasons not described in the reviewed literature, this continued functioning prevents clot formation following cardiac death. Although systemic heparin was administered to the donor patient described in the report by Steen and co-workers,47 many centres performing NHB lung transplantation no longer routinely administer heparin to the donor. In addition to traditional eligibility requirements for NHB organ donation, Steen and co-workers' only other mandatory requirement was that cooling should be initiated within 60 minutes of witnessed arrest or failed resuscitation.

8.1 In-situ techniques for preservation

We recommend that the preferred in-situ technique for preservation in both controlled and uncontrolled DCD be determined by local transplant program protocols and experience.

Key consideration

This recommendation depends on pre-mortem interventions (e.g., cannulation), surgical preferences (e.g., femoral cannulation v. sternolaparotomy) and logistics.

8.2 Ex situ kidney storage

We recommend that machine pulsatile perfusion be available at institutions offering DCD programs where kidneys must be stored ex situ.

Key consideration

Although no prospective studies have compared storage techniques, limited evidence suggests that machine pulsatile perfusion (MPP) is the preferred organ preservation technique as it may permit viability testing and may enhance organ viability.

Summaries of evidence

There are 2 primary means by which the kidney may be preserved following explantation: cold static storage and MPP. MPP was developed before the 1970s and became prevalent thereafter. The technique suffers from several disadvantages, including the cost of the device and consumables, the risk of machine failure and the requirements for an operating technician. MPP was subsequently largely abandoned when no evidence could be found for improved long-term outcome with MPP v. cold storage alone.48

Following a period of enthusiasm for cold storage alone, attention shifted back to the use of MPP in the belief that it might dimish rates of delayed graft function. There was evidence to suggest that delayed graft function contributed substantially to the cost of post-transplant care, increasing requirements for dialysis and lengthening hospital stays. Later reports suggested that it might also contribute to poorer long-term outcomes.49 All of these factors created renewed interest in MPP. Wight and colleagues50 undertook a meta-analysis to determine the effectiveness of MPP relative to cold storage. Although they found that high-quality studies were lacking, they concluded that MPP results in a 20% reduction in delayed graft function in both NHB and heart-beating kidney donation with diminished cost requirements for the care of the transplant recipient when compared with those for patients when cold storage was used.

For donors after brain death, a retrospective United Network for Organ Sharing analysis of 60 827 cadaveric kidneys transplanted between 1988 and 1995 in the United States showed that MPP exhibited a highly significant impact on the need for first-week dialysis and the benefit was increased in high-risk groups (age > 55 years, cold ischemic time > 24 h).51

The benefits of MPP may be related to:

• The continuous delivery of fresh solution to the allograft

• The ability to measure renal resistive indices52

• The ability to measure metabolites such as glutathione S transferase in the perfusate, which are correlated with the extent of renal tubular injury.53

9.1 Initiating a DCD program

We recommend the following before initiating a DCD program:

a) Formal institutional approval within the existing hospital reporting structure

b) An integrated, collaborative approach involving

• Consultation and involvement of hospital stakeholders (e.g., emergency department, ICU, operating room, risk management, pastoral care, bioethics)

• Communication, information and education of staff (e.g., emergency department, ICU, operating room, risk management, pastoral care, bioethics).

• Communication, information and education of the public.

c) Established quality assurance procedures in organ and tissue programs after NDD and tissue donation after cardiocirculatory death

d) Formal support of and collaboration with the regional organ donation organization

e) A risk management plan for DCD centres and partners.

We recommend that the following be in place to start an institutional DCD program:

a) Full-time emergency department (for uncontrolled DCD) and ICU (for controlled DCD) facilities

b) Established end-of-life care protocols

c) An established and effective program in organ donation after NDD

d) Availability of a procurement team

e) Structured support from regional organ procurement organizations.

Measures should be taken to ensure that concerns (real and perceived) for the safety of patients and the public, protection of health care workers and preservation of the integrity of the donation system are safeguarded. These measures may include:

• Auditing by an independent organization (analogous to a data safety monitoring board or research ethics board) or an internal health region or hospital based multidisciplinary group, or both.

• Approval of programs by the regional coroners or medical examiners.

9.2 Initial focus of a DCD program

We recommend that:

a) Centres initiating a DCD program start with kidney donation and expand to include other organs as experience and expertise develop.

b) In their initiation phase, centres proceed only with controlled DCD. Uncontrolled DCD should not be initiated until controlled DCD programs are well established with demonstrated quality assurance.

Key considerations

• Site visits to centres with established programs are advisable.

• Expansion depends on local physician expertise and the development of related programs.

• Centres must have adequate quality controls.

• Some centres may prefer to focus on any organs that may reasonably be used.