If someone has been in cardiac arrest for 10 minutes, the brain is permanently damaged and there’s nothing to do, right?
Not so according to emerging evidence that suggests that the brain shows signs of electrical recovery for as long as an hour into ongoing cardiopulmonary resuscitation (CPR). This time between cardiac arrest and awakening can be a period of vivid experiences for the dying patient before they return to life — a phenomenon known as “recalled death.”
This should be an impetus to increase the use of devices that measure the quality of CPR and to find new treatments to restart the heart or prevent brain injury, experts advised. Cardiologists and critical care clinicians are among those who will need to manage patients in the aftermath.
said Jasmeet Soar, MD, consultant in Anesthetics & Intensive Care Medicine, North Bristol NHS Trust, Bristol, England, and an editor of the journal Resuscitation.
“We know that because if chest compressions are stopped, the person becomes unconscious again,” he said. “This CPR-induced consciousness has become more common when professionals do the CPR because resuscitation guidelines now place a much bigger focus on high-quality CPR — ‘push hard, push fast.’ ”
“People are giving up too soon on trying to revive individuals, and they should be trying more modern strategies, such as extracorporeal membrane oxygenation,” said Sam Parnia, MD, PhD, associate professor in the Department of Medicine at NYU Langone Health and director of critical care and resuscitation research at NYU Langone, New York City.
Brain Activity, Heightened Experiences
Two types of brain activity may occur when CPR works. The first, called CPR-induced consciousness, is when an individual recovers consciousness while in cardiac arrest. Signs of consciousness include combativeness, groaning, and eye-opening, Soar explained.
The second type is a perception of lucidity with recall of events, he said. “Patients who experience this may form memories that they can recall. We’re not sure whether that happens during CPR or while the patient is waking up during intensive care, or how the brain creates these memories, or if they’re real memories or coincidental, but it’s clear the brain does form them during the dying and recovery process.”
This latter phenomenon was explored in detail in a recent study led by Dr. Parnia.
In that study of 567 in-hospital patients with cardiac arrest from 25 centers in the United States and United Kingdom, 53 survived, 28 of those survivors were interviewed, and 11 reported memories or perceptions suggestive of consciousness.
Four types of experiences occurred:
- Recalled experiences of death: “I thought I heard my grandma [who had passed] saying ‘you need to go back.’”
- Emergence from coma during CPR/CPR-induced consciousness: “I remember when I came back and they were putting those two electrodes to my chest, and I remember the shock.”
- Emergence from coma in the post-resuscitation period: “I heard my partner saying [patient’s name] and my son saying ‘mom.’”
- Dreams and dream-like experiences: “[I] felt as though someone was holding my hand. It was very black; I couldn’t see anything.”