What is the Lazarus sign (also known as Lazarus phenomenon)?

From the Guidelines

The Lazarus sign, also known as Lazarus phenomenon, is not explicitly defined in the provided evidence, but based on the context of the discussion on myoclonus and status myoclonus, it can be inferred that the Lazarus sign is likely related to myoclonic jerks or status myoclonus in comatose survivors of cardiac arrest.

Key Points

• The evidence discusses the prognostic value of various clinical signs, including myoclonus and status myoclonus, in comatose survivors of cardiac arrest 1.
• Myoclonus is defined as sudden, brief, involuntary jerks caused by muscular contractions or inhibitions, and status myoclonus is a prolonged period of continuous and generalized myoclonic jerks.
• The presence of myoclonic jerks is not consistently associated with poor outcome, but status myoclonus starting within 48 hours from return of spontaneous circulation (ROSC) is highly predictive of poor outcome 1.
• However, there have been case reports of good neurological recovery despite early-onset, prolonged, and generalized myoclonus, which may be related to the Lazarus phenomenon.

Clinical Implications

• Patients with post-arrest status myoclonus should be evaluated off sedation whenever possible, and EEG recording can be useful to identify EEG signs of awareness and reactivity and to reveal coexistent epileptiform activity 1.
• Clinical studies are needed to evaluate the reproducibility of clinical signs used to predict outcome in comatose post-arrest patients, including the Lazarus sign or Lazarus phenomenon.

From the Research

Definition and Explanation

• The Lazarus sign, also known as the Lazarus phenomenon, refers to a rare and complex movement observed in brain-dead patients, characterized by spontaneous and reflex movements originating from spinal cord neurons 2.
• It is defined as the spontaneous return of circulation after cessation of cardiopulmonary resuscitation (CPR) 3, 4.
• The phenomenon is also described as the return of spontaneous circulation after death, with possible survival discharge 5.

Characteristics and Observations

• The Lazarus sign is observed in a small percentage of brain-dead patients, with a frequency of 13.4% in one study 2.
• The movements associated with the Lazarus sign can be dramatic and complex, including finger and toe jerks, extension at arms and shoulders, and flexion of arms and feet 2.
• The phenomenon can occur after various stimuli, such as an apnea test, oculocephalic test, painful stimulus, or removal of a ventilator 2.
• In some cases, the Lazarus phenomenon can be observed after a prolonged period of cardiopulmonary resuscitation, with return of spontaneous circulation after 20 minutes of death 4.

Clinical Implications

• The occurrence of the Lazarus sign can delay decision-making in brain-dead patients, such as starting a transplantation procedure, due to difficulties in convincing the family or physician of the diagnosis 2.
• The phenomenon highlights the importance of awareness of spinal reflexes in brain-dead patients to prevent delays and misinterpretations of the brain-death diagnosis 2.
• The Lazarus phenomenon also raises questions about the duration of monitoring after failed CPR and the need for established guidelines to prevent the phenomenon 3.