The Lazarus sign or Lazarus reflex is a reflex movement in

brain-dead Brain death is the permanent, irreversible, and complete loss of brain function which may include cessation of involuntary activity necessary to sustain life. It differs from persistent vegetative state, in which the person is alive and some au ...

or brainstem failure patients, which causes them to briefly raise their arms and drop them crossed on their chests (in a position similar to some

Egypt Egypt ( ar, مصر , ), officially the Arab Republic of Egypt, is a transcontinental country spanning the northeast corner of Africa and southwest corner of Asia via a land bridge formed by the Sinai Peninsula. It is bordered by the Medit ...

ian

mummies A mummy is a dead human or an animal whose soft tissues and organs have been preserved by either intentional or accidental exposure to chemicals, extreme cold, very low humidity, or lack of air, so that the recovered body does not decay furt ...

). The phenomenon is named after the Biblical figure

Lazarus of Bethany Lazarus of Bethany (Latinised from Lazar, ultimately from Hebrew Eleazar, "God helped"), also venerated as Righteous Lazarus, the Four-Days Dead in the Eastern Orthodox Church, is the subject of a prominent sign of Jesus in the Gospel of John, ...

, whom

Jesus Jesus, likely from he, יֵשׁוּעַ, translit=Yēšūaʿ, label= Hebrew/ Aramaic ( AD 30 or 33), also referred to as Jesus Christ or Jesus of Nazareth (among other names and titles), was a first-century Jewish preacher and religiou ...

raised from the dead according to the

Gospel of John The Gospel of John ( grc, Εὐαγγέλιον κατὰ Ἰωάννην, translit=Euangélion katà Iōánnēn) is the fourth of the four canonical gospels. It contains a highly schematic account of the ministry of Jesus, with seven "sig ...

Causes

Like the knee jerk reflex, the Lazarus sign is an example of a reflex mediated by a

reflex arc A reflex arc is a neural pathway that controls a reflex. In vertebrates, most sensory neurons do not pass directly into the brain, but synapse in the spinal cord. This allows for faster reflex actions to occur by activating spinal motor neurons w ...

—a

neural pathway In neuroanatomy, a neural pathway is the connection formed by axons that project from neurons to make synapses onto neurons in another location, to enable neurotransmission (the sending of a signal from one region of the nervous system to an ...

which passes via the spinal column but not through the brain. As a consequence, the movement is possible in brain-dead patients whose organs have been kept functioning by life-support machines, precluding the use of complex involuntary motions as a test for brain activity. It has been suggested by

neurologists Neurology (from el, νεῦρον (neûron), "string, nerve" and the suffix -logia, "study of") is the branch of medicine dealing with the diagnosis and treatment of all categories of conditions and disease involving the brain, the spinal c ...

studying the phenomenon that increased awareness of this and similar reflexes "may prevent delays in brain-dead diagnosis and misinterpretations." The reflex is often preceded by slight shivering motions of the patient's arms, or the appearance of

goose bumps Goose bumps, goosebumps or goose-pimples are the bumps on a person's skin at the base of body hairs which may involuntarily develop when a person is tickled, cold or experiencing strong emotions such as fear, euphoria or sexual arousal. The ...

on the arms and torso. The arms then begin to flex at the elbows before lifting to be held above the

sternum The sternum or breastbone is a long flat bone located in the central part of the chest. It connects to the ribs via cartilage and forms the front of the rib cage, thus helping to protect the heart, lungs, and major blood vessels from injury. Sha ...

. They are often brought from here towards the neck or chin and touch or cross over. Short exhalations have also been observed coinciding with the action.

Occurrences

The phenomenon has been observed to occur several minutes after the removal of

medical ventilator A ventilator is a piece of medical technology that provides mechanical ventilation by moving breathable air into and out of the lungs, to deliver breaths to a patient who is physically unable to breathe, or breathing insufficiently. Ventilators ...

s used to pump air in and out of brain-dead patients. It also occurs during testing for apnea—that is, suspension of external breathing and motion of the lung muscles—which is one of the criteria for determining brain death used for example by the

American Academy of Neurology The American Academy of Neurology (AAN) is a professional society representing over 38,000 neurologists and neuroscientists. As a medical specialty society it was established in 1948 by A.B. Baker of the University of Minnesota to advance the ...

. Occurrences of the Lazarus sign in

intensive-care unit 220px, Intensive care unit An intensive care unit (ICU), also known as an intensive therapy unit or intensive treatment unit (ITU) or critical care unit (CCU), is a special department of a hospital or health care facility that provides intensiv ...

s have been mistaken for evidence of resuscitation of patients. They may frighten those who witness the movement, and have been viewed by some as miraculous events.

References

{{DEFAULTSORT:Lazarus Sign Reflexes Signs of death

Causes

Occurrences

See also

References