Non-heart-beating organ donation in patients with amyotrophic lateral sclerosis: Why is general anaesthesia necessary?

摘要

Smith and colleagues reported controlled non-heart-beating (NHB) organ donation from two patients with amyotrophic lateral sclerosis (ALS). They alluded to the challenges of titrating medication to relieve distress in anticipation of terminal withdrawal of life support and multi-organ procurement in ALS patients. We elaborate on (1) the method to assess distress and (2) the medication to alleviate this distress.The neural pathways and interrelationship of the two components of consciousness- (1) level of consciousness (i.e., wakefulness) and (2) content of consciousness (i.e., subjective awareness)- are poorly characterized. Experimental evidence suggests that subjective awareness of external and internal sensory stimuli may be independent of wakefulness.Furthermore, electroencephalography (EEG) can detect awareness that may not be discernible from bedside clinical examination. ALS is a neurodegenerative disease of the peripheral and central motor nervous system. ALS donors generally have normal peripheral and central sensory nervous system and intact higher brain structures. Higher brain structures can retain their neural reactivity for several minutes after circulatory arrest and can be detected by electric surges on EEG. Non-heart-beating donors with catastrophic brain injuries also display acute surges on EEG.