American scientists from the New York University School of Medicine have discovered that the human brain can retain signs of consciousness for tens of minutes after cardiac arrest, provided that the patient is resuscitated at this time. The study was published in the scientific journal magazine Animation.
When the heart stops, the organ suddenly stops functioning, stopping blood flow to the brain and other vital systems of the body. The person falls into a coma and may die quickly if he or she is not given immediate help.
Studies have shown that many people, even while seemingly unconscious, retain memories of what they heard and felt when their hearts were not beating.
Experts identified 567 patients who had heart attacks. During resuscitation, a tablet computer that played images and sounds was placed on their chest to test their memory in this state. The cardiopulmonary resuscitation (CPR) procedure took an average of 26 minutes, but in some cases it could take up to an hour.
Doctors from this group were able to restore blood circulation in 213 people, but only 53 were able to recover and be discharged from the hospital.
Twenty-eight survivors were interviewed about their conscious experiences during cardiac arrest. Eleven people reported memories and sensations indicating the presence of consciousness, although there were no apparent signs. These experiences included various visions as well as emerging from a coma during or after resuscitation.
The experiences reported by these 11 individuals can be divided into three categories: recovery from coma during or after resuscitation, dream-like experiences, and memories of cardiac arrest.
Another 126 people who had a heart attack were interviewed. Their stories revealed similar experiences as well as delusional and misinterpretations of medical events. For example, one patient mistook the sensation of intravenous medication administration for the heat of hellfire.
Participants who awoke from comas during resuscitation often described the effects of the procedure on their bodies. During this period, they said that they felt pressure due to electrodes, pain, pressure on the chest, and that they also heard the doctors’ conversations.
In some cases, this was accompanied by images of rainbows, fish, humanoids, wooden buildings and other objects, as well as a feeling of leaving the body and observing oneself from the outside.
The researchers also used electroencephalography (EEG) to monitor the brain state of the resuscitated people. The EEG data showed different patterns. In 47% of the cases, there was primarily a lack of cortical activity. However, brain activity returned in 40% of patients. Returned to normal after cardiopulmonary resuscitation began. This was the first case in which biomarkers of consciousness were recorded during cardiac arrest and CPR.
Scientists stated that the study sheds light on the possible conscious experiences of people having a heart attack.
experts before developed Mobile application to detect heart failure.