To the Editor The Uniform Determination of Death Act defines death as a singular phenomenon by irreversible cessation either of circulatory and respiratory functions or of all brain and brainstem functions.1 Growing demand for transplantable organs has refocused attention on the circulatory standard of declaring death in non-heart-beating donation (NHBD).2 Variable (75 seconds to 5 minutes) cardiac mechanical asystole (or absent arterial pulse) is the United States' circulatory standard.2 This standard is based on expert opinion of zero chance of spontaneous recovery of heart and brain functions after 65 seconds of mechanical asystole.3 Hearts recovered from donors may have normal native mechanical and electrical functions after transplantation3; therefore, mechanical asystole can be reversed. Others conceded that donors in NHBD might not necessarily be dead, either by cardiorespiratory (circulatory standard) or brain (neurological standard) criteria.4 We argued that antemortem and postmortem interventions performed for organ preservation in donors are neuroprotective, preventing rapid deterioration or irreversible cessation of brain functions after mechanical asystole.5 Auyong et al. provided compelling evidence for studying brain function in donors declared dead in NHBD.6 In 3 non-heart-beating donors, the authors demonstrated reproducible surges in Bispectral Index scores from real-time electroencephalograms. Chawla et al.7 reported similar Bispectral Index score surges in 7 cases within minutes after being declared dead, i.e., pulseless, motionless, and asystolic on the electrocardiogram. The clinical and neurological significance of delayed surges of brain electric activity after mechanical asystole is unknown. However, nocioception and awareness are real concerns during surgical procurement in NHBD. General anesthesia is not administered to donors because they are assumed dead with no discernable brain functions. This is of particular concern because age eligibility for NHBD starts from newborn and includes donors with normal brain function before sustaining mechanical asystole (e.g., end-stage musculoskeletal disease, pulmonary disease, and high spinal cord injury) (available at http://optn.transplant.hrsa.gov/policiesAndBylaws/bylaws.asp; accessed March 20, 2010).8 We agree with Auyong et al. that donors should be routinely monitored with electroencephalogram for dosing of anesthetic and opioids drugs during surgical procurement. Mohamed Y. Rady, MD, PhD, FCCM Joseph L. Verheijde, PhD, MBA, PT Department of Critical Care Medicine Departments of Biomedical Ethics, Physical Medicine, and Rehabilitation Mayo Clinic Phoenix, Arizona School of Life Sciences Center for Biology and Society Arizona State University Tempe, Arizona [email protected]
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