Click on picture to read about G.M. Woerlee's newest book!
Click hier om een recensie van "Eindeloos Bewustzijn" te lezen
Cardiac Arrest and Near Death Experiences
© G.M. Woerlee
Cardiac arrest is a rapidly fatal medical disaster which when untreated always causes death. Cardiac arrest is a collective name for the effects of an abnormal heartbeat - heartbeat which has stopped, or which is so abnormal that the heart no longer functions as a pump. And the function of the heart is to pump blood, circulating blood around the organs and tissues of the body. The flow of blood into organs transports oxygen, nutrients, hormones, and many other substances into these tissues, while the flow of blood out of the organs removes waste carbon dioxide, waste products of metabolism, hormones, and other substances. All organs and tissues of the body fail and die when this flow of blood ceases, and of all the organs of the body, the eyes and the brain are most sensitive to the effects of failure of the normal flow of blood.
Sudden cessation of the flow of blood to the head as occurs during cardiac arrest causes failure of the eyes and the brain manifesting as blindness and paralysis of all muscles after 3-19 seconds, followed by loss of consciousness after 4-20 seconds (1). This period of consciousness remaining after the heart stops is why some cardiac arrest patients complain bitterly when painful resuscitative measures are begun before they lose consciousness. This is why some people may remain conscious for several seconds after being shot or stabbed in the heart.
Sam Parnia (2) and Pim van Lommel (3) reported studies of thorough standardized interviews of hundreds of patients who survived resuscitation for cardiac arrest. They reported that between 11-18% of these cardiac arrest survivors underwent near death experiences (NDEs). These were wonderful, exceedingly well executed studies, especially that of Pim van Lommel. It required unbelievable tenacity and effort over many years to complete these studies. Yet in the discussions concluding both of these excellent studies, the authors of both articles said they were unable to understand how such conscious experiences could arise when the patients were "unconscious" during the period of cardiac arrest.
This is surprising! These authors appeared to have forgotten the very purpose of heart massage as applied during cardiac resuscitation. Cardiac resuscitation is not a passive affair where physicians and nurses stand back, arms crossed, while calmly observing a person with a cardiac arrest gradually fade away, calmly waiting for that person to spontaneously revive without any activity on their part, except perhaps for interested observation on the part of the observing physicians and nurses. Instead, physicians and nurses in modern Western European hospitals have a very standard reaction pattern when confronted with a person with a manifest cardiac arrest. They sound an alarm summoning a special resuscitation team, while at the same time hurling themselves upon the dying person like a pack of wild dogs. They place a hard plank under the chest of the person, perform artificial respiration with a mask and balloon, insert an intravenous line through which medicines necessary to treat the cause of the cardiac arrest can be administered, and perform cardiac massage.
Cardiac massage is not a gentle and passive procedure - the person applying such massage vigorously and forcefully compresses and releases the chest 60-120 times per minute - it is a tiring and sometimes exhausting procedure. The purpose of cardiac massage is not a form of fitness training - the purpose of heart massage is to pump blood around the body during periods that the heart does not pump because of a cardiac arrest. The heart is a bag made of muscle tissue in which there are four one-way valves. Compression of the chest forces blood out of the heart and the chest, and because of the one-way valves in the heart, this emerges out of the heart into the arteries conducting it into the various organs and tissues of the body. Releasing the chest causes the chest to rebound to its' original form, creating a negative pressure within the chest and heart, sucking blood into the chest and the heart. Compression of the chest repeats this cycle. Cardiac massage pumps blood, circulating it around the body when the heart no longer does this. Cardiac massage is always applied during cardiac arrest - failure to do so means no blood is pumped around the body of the person with a cardiac arrest, and that person will die.
Nearly all of the patients involved in the studies of Van Lommel and Parnia were certainly unconscious due to lack of circulation at the time the resuscitating physicians and nurses arrived. As to whether their brains were active at this time, or whether they has a flat electroencephalogram (EEG) at the time people arrived to resuscitate them - who knows. Certainly in the Netherlands at the time Van Lommel performed his study, as well as at the present time in the Netherlands, and in the whole world for that matter - NO ONE EVER attaches an EEG measuring device to the heads of people undergoing resuscitation for sudden cardiac arrest. I know this to be a fact, because as an anesthesiologist working in the Netherlands, I also assist in the resuscitation of many people with cardiac arrest. And during a long career in anesthesiology in three countries, I have never seen or heard of an EEG machine being attached to the head of people undergoing resuscitation for sudden cardiac arrest. This means that all statements about these patients having had a "flat EEG", or flatlined at the time the resuscitating people, ambulance, or other medical personel arrived are very likely correct, but not an absolute certainty. All anyone can say is that the EEG is certainly flat by 1-3 minutes after the heart suddenly stops beating (1). This is a known fact. However, once cardiac massage was commenced in these people, blood was pumped from their hearts, restoring some circulation again, so sustaining the life in their brains and bodies until normal heartbeat and circulation could be restored. Restoration of some degree of blood circulation through the brains of these people, means that some degree of brain function, and hence some EEG activity was also restored. And in some of these people undergoing cardiac resuscitation, the efficiency of the cardiac massage was such that enough blood and oxygen was pumped around their bodies to restore partial, or even full consciousness, together with the appropriate EEG activity. Accordingly, statements claiming that all people are unconscious, and all people have a "flat EEG” while undergoing active cardiac resuscitation are pure speculation, and likely to be quite incorrect.
But how much blood is pumped as a result of cardiac massage, and how much blood must be pumped to sustain consciousness? Here are some figures.
What flow of blood through the brain is needed to sustain consciousness?
Studies of the efficiency of cardiac massage reveals that cardiac massage generates a flow of blood greater than 1730 mls/minute in no more than 20-24% of persons undergoing cardiac massage. This means that as many as 20-24% of people undergoing cardiac massage during a cardiac arrest may be partially, or fully conscious. Most of these people will only be partially conscious, but a few may be fully conscious. And these people may be conscious but unable to move, because even though the flow of blood supplying oxygen to their brains may be sufficient to sustain consciousness, it may not be sufficient to enable normal movement. This sounds surprising, but a person undergoing moderate to severe brain oxygen starvation due to cardiac arrest, (or any other form of oxygen starvation), can be in a condition in which they are paralyzed and unable to move, yet conscious and able to hear all that is happening about them (1, 7). This is the situation in which the patients reporting NDEs after successful resuscitation from cardiac arrest found themselves during their NDEs. And all these people were not flatlined, instead they had an EEG appropriate to their clinical situation. But no-one knows this, because no-one ever measures the EEG of patients undergoing resuscitation for sudden cardiac arrest.
All this explains how it is that unmoving, unresponsive, apparently dead people undergoing cardiac resuscitation for cardiac arrest can undergo conscious experiences such as a NDE. And the fact that oxygen starvation inhibits formation of memories explains why only 11-18% of these people can undergo, or rather, remember such a conscious experience. My book "Mortal Minds" provides a more extensive discussion of how the functioning of the body in these situations can generate all the other phenomena associated with these NDEs, such as the experience of light, the tunnel, the sensations of ineffability, life review, out of body experiences, etc (8).
Oxygen starvation due to cardiac arrest generates such a standard set of changes, that it is possible to describe a stereotype NDE generated by a cardiac arrest:
The flow of blood to the body stops because the heartbeat is so abnormal that no blood is pumped by the heart, or the heart stops beating, and the brain is subjected to total oxygen starvation. The small reserve of oxygen within the blood and the cells of the brain is soon exhausted, causing rapidly progressive oxygen starvation. Oxygen starvation of the brain first causes failure of prefrontal cortex function, causing the patient to feels serene and indifferent as he/she gradually "fades away". Subsequently, oxygen starvation of the brain causes failure of those parts of the brain called the supplementary motor cortex, the frontal eye fields, Broca's speech cortex, and the primary motor cortex. Failure of these parts of the brain causes the eyes to stare fixedly straight ahead, the person is paralyzed and unable to move or speak, even when they try to do these things. At this time the retina also fails due to oxygen starvation, and the patient feels their vision failing - they see grey or everything becomes dark. Yet surprisingly they are able to hear quite well at this time because hearing is one of the last senses to fail.
Within 5-20 seconds the person is unconscious, can sense nothing and experience nothing. Their body is discovered and resuscitation with heart massage commences. About 1 in 5 (20%) of all people performing cardiac massage is so efficient their efforts generate a flow of blood around the body sufficient to restore consciousness. Sometimes this flow of blood is sufficient to restore normal consciousness, but usually it is just sufficient to restore some degree of consciousness, but not normal consciousness. Normal consciousness takes longer to return than it takes to restore pumping action of the heart.
Oxygen starvation of the eyes is somewhat reversed, restoring some central vision. At the same time, oxygen starvation, stress, and adrenaline administered as part of the resuscitation medication causes the pupils to be wide open - so patients see a bright light at the end of a tunnel. Furthermore, abnormal interpretation of bodily sensations, together with abnormal muscle spindle function generates sensations of movement and floating - so the person perceives themselves to be traveling down this tunnel towards the bright light. Restoration of entire retina function restores the ability to see light, but does not restore normal brain function, nor does it restore normal pupil size (adrenaline effect). So the person perceives themselves to be passing out of the tunnel into the light - they are "enveloped by the light".
At this same time, having passed into the light, while consciousness is gradually returning, but still abnormal, a person may undergo wondrous hallucinatory experiences. Such experiences are partly delusory due to misinterpretation of bodily sensations, sometimes due to abnormal electrical activity in parts of the brain such as the hippocampus which is very sensitive to oxygen starvation. The latter can also generate sensations of life review, while abnormal electrical activity in the rest of the temporal lobe can also generate sensations of immaterial presences, or of religious figures.
The resuscitation progresses, and consciousness returns to near normal. The resuscitating doctors and nurses speak, and what they say, what they do, and all other sounds are heard by the patient, while still paralyzed due to oxygen starvation and apparently unconscious. The doctors and the nurses regularly open the eyes of the patient to shine a light into the eyes to check papillary reactions to light. And sometimes the eyes of a patient remain open during a resuscitation. So some patients can see what is happening around their bodies during their resuscitation. These sensations, combined with abnormal sensory information from muscle spindles, combined with abnormal interpretation of muscle spindle sensations can generate sensations of displacement and movement out of the body - all these things combine to generate out of body experiences during which the person sees and hears everything occurring to their body and around their body. Failure of prefrontal function means they still feel calm and serene at this time, as well as indifferent to pain.
Finally, resuscitation is successful - normal pumping action of the heart is restored, and the person eventually awakens. Some peopleremember all these wondrous experiences, and tell others what happened during the period they lay still and motionless, apparently unconscious, during the resuscitation for their cardiac arrest
So supernatural or paranormal explanations are not needed to explain what those undergoing NDEs during resuscitation for cardiac arrest experience. Nor are explanations such as a soul, or a mind which exists separately from the body required. The functioning of the body explains all aspects of NDEs occurring during cardiac resuscitation.