Posted in Psychology & Medicine

Agonal Breathing

When a person is on the verge of death, they may show a very strange pattern of breathing. They will begin gasping for breath, take deep laboured breaths, begin to make strange noises and possibly have some muscle jerks (which may look like a seizure). The breathing makes it look as if the person is taking a deep breath and sighing, while gasping every now and then irregularly. This is called agonal breathing and it is most likely caused by an oxygen-starved brain sending weak signals to try kick up the respiratory drive for more oxygen.

Agonal breathing is not uncommon in cases of cardiac arrest. It is important to note that agonal breathing is not an efficient form of breathing and thus it cannot be said that the victim is “breathing” when this occurs. Because it looks like the patient is taking deep breaths, bystanders may be fooled into thinking that they have been resuscitated and have begun breathing again. But this is not the case and the patient is still clinically dead. Ergo, one should not stop CPR even if the patient begins taking deep breaths and sighs. The presence of agonal breaths usually indicate a better outcome for the patient.

(Link to video examples of what agonal breathing looks like: http://emsbasics.com/2011/04/21/what-it-looks-like-agonal-respirations/)

Posted in Psychology & Medicine

Lazarus

In the New Testament of the Bible, there is a scene where Jesus resurrects a man by the name of Lazarus back four days after his death. This “miracle” is of course a fictitious event, but nonetheless, the name Lazarus has come to symbolise resurrection after death. For example, there are two actual medical conditions named after Lazarus, both related to death.

The first is called Lazarus phenomenon, where a person who is declared to be clinically dead spontaneously returns to life. This is an extremely rare event that has only been recorded in about 30 cases. In most of these cases, the patients had suffered a cardiac arrest, with all attempts at resuscitation (e.g. CPR, adrenaline) had failed. Sometime after the person was declared clinically dead (usually around 5~10 minutes), the person’s circulatory system would suddenly start on its own and the person would be “resurrected” (quite literally). In one case, a 61 year-old woman was declared officially dead after her heart stopped and her vitals did not return after continuous resuscitation. At the morgue, however, she was found to have a pulse and breathing on her own. She later sued the hospital for the neurological and physical injury caused by oxygen deprivation during her death. There is even a case report of a patient who returned to life two and a half hours after dying (although he died again 3 weeks later).

Of course, the Lazarus phenomenon is not a miracle. In most cases, it is hypothesised that when resuscitation is attempted then stopped, there is a rare chance of the relieving of pressure causing blood to fill the heart, causing a sudden expansion and kickstarting the electrical circuit. Other factors that may influence this is hyperkalaemia resulting from ischaemia and high doses of adrenaline given to the patient during resuscitation having a delayed effect.
Because of this rare “complication” of death, doctors are advised to observe the patient for about 10 minutes after declaring them dead. Just in case.

The second is called Lazarus sign and it occurs not in dead patients, but brain-dead patients. Brain-dead patients are immobile as their higher functions such as cognition and motor functions are destroyed. However, there are rare cases where the brainstem is somehow stimulated, triggering a reflex arc from the spinal cord. This reflex is seen as the patient suddenly raising their arms and dropping them on their chest in a crossed position, much like Egyptian mummies. As the spinal cord is not usually damaged in brain-dead patients, this reflex arc is possible, similar to a knee jerk reflex. The Lazarus sign should not be misinterpreted as a sign that a brain-dead patient is conscious, as it is an involuntary movement. However, it has been mistaken for the resuscitation of a patient, or in some cases, as a miracle.

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Posted in Psychology & Medicine

Sudden Death

Unlike diseases such as tuberculosis or cancer, some disease processes are known to kill a human being within an hour of onset. Other than the obvious causes such as decapitation, massive bleeding or any other trauma-related injuries, these diseases tend to be cardiac or respiratory in origin.

A common example is coronary artery disease, where the blood vessel providing blood to an area of the heart becomes completely blocked by stenosis (narrowing, often by atherosclerosis) or a clot. This results in immediate ischaemia (lack of oxygen) to heart muscles, which causes cell death. This produces scar tissue which disrupts the electrical activity of the heart, which may lead to a condition called ventricular fibrillation where the heart beats in an uncontrolled, erratic manner. When in VF, the heart effectively becomes useless as it cannot coordinate proper pumping function. Blood circulation stops and the patient goes in to multiple organ failure (the brain goes first) within a very short time. Although it can kill within a short time, early identification and treatment may be able to prevent VF from occurring and save the patient’s life. If VF does occur, it is crucial to begin CPR or use a defibrillator if available.

VF can also occur in other situations. For example, there is a genetic condition called long QT syndrome which predisposes the patient to spontaneous arrhythmias (electrical abnormalities in the heart). Even becoming too excited can sometimes set off a VF in some LQTS patients, thus they require an implantable cardioverter-defibrillator (ICD) to shock their heart back in to normal rhythm every time they develop an arrhythmia.

Some other causes of sudden death include: aortic dissection (tearing of the aorta that may cause massive internal bleeding), pulmonary embolism (a clot obstructs blood flow in the lung, stopping circulation), commotio cordis (a blow to the heart at a certain moment in the heart rhythm triggers VF), ruptured brain aneurysm (ballooning of an artery in the brain), anaphylaxis (severe allergic reaction that cuts off airflow to the lungs) and poisoning (various mechanisms, mainly related to disrupting cellular function).

Death can strike swiftly, even from within your body.

Posted in Science & Nature

Shrew

A shrew is a small rodent, similar in size to a rat, that has many fascinating characteristics.

Funnily enough, this animal has a notorious name in history. Ancient Egyptians considered shrews the spirits of darkness and the English believed that if a shrew ran over a lying animal, the animal would suffer great pain. The name shrew comes from the Middle Age English word shrewe, which meant “evil” or “scolding person”.
This is probably attributable to the putrid smell a shrew makes when threatened, and its poisonous bite.

Despite its tiny figure, the shrew has the greatest surface-area-to-weight ratio out of any mammal on the face of the Earth. Because of this, they also have a high heat expenditure, meaning they have to eat constantly to replenish the energy. This means that they sometimes die from starvation during prolonged naps.
Also, they have an extremely high heart rate, averaging about 700 beats per minute. When they are frightened, the heart rate can spike leading to cardiac arrest. For example, shrews are known to die from being frightened by the sound of thunder.

An animal that dies if it naps too much or when thunder strikes – the shrew is a very sad animal.