What are signs of brain death?

• View PDF

Volume 8, Issue 1, April 2013, Pages 1-6

https://doi.org/10.1016/j.jtumed.2013.02.001Get rights and content

A woman lies in a bed at The Johns Hopkins Hospital. Aided by a ventilator, her lungs inflate, deflate, and fill again. Her heart beats and her skin is warm. But her eyes stay closed and she does not react to stimuli such as pain and light. 

Is she alive or dead?

If you’re unsure, or if the question makes you uncomfortable, you’re not alone. The hypothetical case described here reflects a real problem: the inherent difficulties of diagnosing and accepting brain death.

The topic was the focus of a September Ethics for Lunch discussion in the Chevy Chase Bank Auditorium of The Johns Hopkins Hospital, hosted by the Berman Institute of Bioethics.

The panel was moderated by anesthesiologist and critical care specialist Robert Stevens, who says the line between life and death, once clearly perceptible in the form of a beating heart, is now sometimes harder to see because of advances in lifesaving technologies.

The modern intensive care unit can keep a person with severe brain injuries alive, he says, but may also mask evidence that the person has died. The shift from a deep coma to brain death—permanent cessation of all brain function—may not be immediately obvious to an untrained observer. Yet recognizing this transition from life to death is critical for families, the medical team and potential organ recipients.

When a patient dies, doctors stop treatment and instead focus on organ viability. The body is kept on life-support machinery if the patient was a registered organ donor or while the family makes decisions about organ donation.  

To help clinicians make a brain death diagnosis, The Johns Hopkins Hospital in June 2016 created a Determination of Death by Neurological Criteria Support Team.

Here’s how it works: A patient arrives in the emergency room after an overdose, car accident or other trauma that caused extensive brain injury. Doctors do everything they can to stabilize the patient, but his brain may have suffered irreversible damage.

When attending physicians suspect a patient is brain-dead, they may opt to call a consultant—a Johns Hopkins neurologist, neurosurgeon or critical care specialist with experience and training in two different, but related, areas: the techniques used to determine death, and communicating the nuances of the difficult situation with primary care teams and family members.

The consultant performs a full neurological examination to determine if there are any signs of brain or brainstem function. This includes assessing the drive to take a breath, determining whether pupils react to light, and swabbing the back of the throat to elicit a gag reflex. The neurological examination must be repeated at least once after a minimum interval of six hours, to ensure that brain function is not temporarily suppressed by factors such as high doses of narcotics or intense cold. 

The support team helps those consultants by providing guidance and answering questions. “Our only advantage is experience, because we handle more of these cases,” says neurologist and neurocritical care specialist Adrian Puttgen, who forms the group with anesthesiologist and neurocritical care specialist Adam Schiavi, and neurologists Rafael Llinas and Brett Morrison. “This team is written into our hospital policy. We monitor in the background and come in as needed when there’s a question.”  

Because of that support, brain death determinations take less time than in the past. “We owe it to the families to resolve the question of whether a patient is alive or dead as quickly as possible,” says Puttgen. “Otherwise, it’s a state of limbo.”

A brain death diagnosis is nearly always confusing and overwhelming to family members. In a few states, though not Maryland, doctors must accommodate the preferences of families who refuse to accept the diagnosis for religious reasons.

That happened in 2013, when the parents of Jahi McMath moved the13-year-old from a California hospital to one in New Jersey after a brain death diagnosis following tonsillectomy complications. Her body remains attached to life-support machinery.   

“Most people have this notion that you’re recognizably alive and then you’re recognizably dead,” says Schiavi. “What’s happened is that our technological ability to sustain life has moved faster than our moral capacity to deal with the implications.”

The support team is helping. “We are taking active steps to change the culture, not only for families but for physicians as well,” he says.

Watch the Ethics for Lunch panel discussion. 

Johns Hopkins' medical concierge services offer complimentary assistance with appointments and travel planning. Request free assistance:

• Serial determination of clinical criteria

• Sometimes electroencephalography (EEG), brain vascular imaging, or both

For a physician to declare brain death, a known structural or metabolic cause of brain damage must be present, and use of potentially anesthetizing or paralyzing drugs, especially self-administered, must be excluded.

If hypothermia is present, a core temperature < 35° C must be increased slowly to > 36° C, and if status epilepticus is suspected, EEG should be done. In adults, after all complicating medical conditions have been excluded and a comprehensive neurologic examination with the required testing has been done, brain death can be confirmed. Some states advise clinicians to do two separate examinations separated by at least 48 hours in children; this approach is not consistently recommended or required for adult patients (see table Guidelines for Determining Brain Death (in Patients > 1 Year) Guidelines for Determining Brain Death (in Patients > 1 Year*)†

• Assessment of pupil reactivity

• Assessment of oculovestibular, oculocephalic, and corneal reflexes

Sometimes EEG or tests of brain perfusion are used to confirm absence of brain activity or brain blood flow and thus provide additional evidence to family members, but these tests are not usually required. They are indicated when apnea testing is not hemodynamically tolerated and when only one neurologic examination is desirable (eg, to expedite organ procurement for transplantation).