Irreversibility is consistent with legal
The determination of death affects all physicians, and modern medical technology has complicated this process. The availability of life-sustaining interventions such as CPR, mechanical ventilation, heart-lung support machines, ventricular assist devices, and organ transplantation has obscured our ability to distinguish between the seemingly discrete states of life and death.
Explore This IssueACEP News: Vol 29 – No 09 – September 2010
The ethical norm for organ donation is the “dead donor rule,” which states that living patients must not be killed by organ retrieval. For transplantation to be successful, the arrest of circulation and resulting warm ischemic injury must be minimized. This is partially overcome when death is determined using neurologic criteria because the brain dead donor remains on a ventilator and circulation persists until surgical removal of organs.
Brain dead donors continue to be the preferred source of transplantable organs, but the persistent shortage of organs has led to the reemergence of donation after cardiac death (DCD). DCD programs account for the largest incremental increase in organ donation in active U.S. programs. Accompanying this renewed emphasis on DCD is the requirement to determine death as rapidly as possible following cardiac arrest, to minimize ischemic organ injury.
Death is generally understood to be based on the irreversible cessation of either brain or circulatory/respiratory functions. The language and notion of irreversibility is problematic, and the Uniform Determination of Death Act did not define the term. Its interpretation has evolved, given the advances in the technical ability to sustain vital functions.
Hospital deaths are almost always preceded by a decision to forego some form of life-sustaining intervention. So does “irreversible” mean “cannot be reversed under any circumstances” or “will not be reversed” in accordance with appropriate care?
DCD has enhanced the rigor of the determination of death after cardiac arrest. However, there is a lack of consensus on how long circulation must cease for a person to be determined dead. Internationally, this period varies from 75 seconds to 10 minutes.
Irreversibility of circulation after cardiac arrest is defined as a state in which vital functions cannot return on their own and will not be restored by medical interventions. This applies to the setting of a legally valid refusal of CPR by the patient directly, through advance directive, or via the patient’s decision maker. In this way, irreversible is defined as not physically possible to reverse without violating the law on consent.
The existing practices for determining death during controlled DCD, where a consensual decision has been made to withdraw life support and withhold CPR, are consistent with medical, ethical, and legal standards permitting organ donation.