Lazarus Sign, a Misnomer to an Anatomical Spinal Reflex.

Abstract

The Lazarus sign is a well-documented spinal reflex observed in brain-dead patients, characterized by involuntary upper limb movements that can resemble voluntary gestures. Initially described during the 1980s, this phenomenon has contributed to ongoing discussions about the physiological basis of spinal reflexes and their role in assessing brain death. The Lazarus sign was once considered a diagnostic challenge, but recent research reports confirm that it originates solely from the spinal cord, independent of brainstem or cortical activity. However, recent studies also suggest that spinal reflexes in brain-dead patients, including the Lazarus sign, can be more variable than previously thought, occurring in multiple limb regions beyond the upper limbs. Prolonged survival in brain-dead patients exhibiting the Lazarus sign has also raised new questions about its physiological significance. Its recognition has helped refine brain death criteria, ensuring accurate diagnoses and minimizing misinterpretations in critical care and organ donation settings. PubMed-indexed studies and backward citations were reviewed. Studies were included if they explicitly described spinal reflexes in brain-dead patients, examined neurophysiological mechanisms, or provided clinical observations on the Lazarus sign. Exclusion criteria included studies focusing solely on brainstem activity without considering spinal reflexes or case reports lacking detailed methodology. These investigations explored the prevalence, neurophysiological mechanisms, and clinical significance of the Lazarus sign. Research highlights its variable presentation, its occurrence in up to 40% of brain-dead patients, and its potential to be misunderstood by families and healthcare providers. The sign does not indicate residual brain function, but it reinforces the need for clear communication in end-of-life care. Future research should focus on standardizing diagnostic protocols, educating clinicians, and addressing ethical concerns. Integrating this knowledge into brain death assessments will enhance clinical decision-making and patient management.