Last week, my son had a car accident. Although he survived, he is still in a coma. After three days in the ICU, we were informed that he had suffered brain death and had no chance of recovery.

Strangely, when touching my son's body, I could still feel his heartbeat and breath, but he couldn't move. Does brain death mean a vegetative state?

Many people share the same question as this mother. Let's explore what "brain death" really means.

I. What is Brain Death?

Medically speaking, brain death refers to the complete and irreversible loss of all brain functions, with no chance of recovery. The degree of loss is essentially equivalent to the standards for death by cardiac arrest. Although a person may still have a heartbeat and breath, it's similar to a fish that's been decapitated on a cutting board; even though the body may still wriggle, it's only an artificial form maintained by bioelectrical phenomena.

Currently, the medical community distinguishes between two types of death: cardiac arrest and brain death. In general, death is defined as the cessation of all signs of life, including respiration, heartbeat, and reflexes. Brain death is the same and irreversible. However, there have been reports of patients "coming back" from brain death, but these exceptional cases are mainly due to misdiagnosis by doctors.

Brain death is an irreversible condition; it is real death, meaning the patient cannot revive. The notion that a brain-dead patient can still regain consciousness is a misconception.

Therefore, the criteria for determining brain death are stricter. Typically, two experts must conduct separate tests and reach a consensus before declaring brain death, and all medical indicators must be met.

• The patient has been in a coma with severe brain damage from trauma or massive brain hemorrhage, not due to hypothermia or poisoning.

• The patient is in a deep coma and does not respond to painful stimuli; the brainstem cannot perform reflexes, including the loss of pupillary light reflex, corneal reflex, and oculomotor reflex; the patient cannot breathe without mechanical ventilation. All three critical clinical tests are met.

• There is also supporting evidence such as electroencephalography (EEG) and cessation of cerebral circulation.

II. How Do Doctors Determine That a Patient Will Die in One or Two Days?

In many movies and TV shows, after a patient becomes seriously ill, doctors often advise the family to prepare for the worst-case scenario as soon as possible after completing resuscitation efforts, because the patient's time is running out. Some might wonder, how do doctors know that a patient will die in one or two days? What do they base this judgment on?

1. Diagnosis of the Illness

First, based on clinical examination indices, symptoms, and the patient's medical history, the patient's condition can be comprehensively assessed. In severe cases like tumors, organ failure, or brain death, where recovery is essentially impossible, doctors will estimate the remaining survival time based on clinical experience. Furthermore, critically ill patients often show signs of deterioration, such as drowsiness, inability to speak, and difficulty swallowing. Symptom evaluation also helps determine the stage of the patient's illness.

2. Test Indicators

Generally, we primarily consider basic indicators such as body temperature, blood pressure, and pulse. If body temperature drops sharply, affecting circulation to the limbs, weak or even difficult-to-find pulse, and a sharp decrease in blood pressure that cannot be restored by conventional treatments, these are usually considered warning signs.

3. Clinical Experience

Doctors often have rich clinical experience. The more cases they encounter, the better they can manage the patient's condition. Many experienced doctors can make a basic judgment about the patient's condition by combining different indicators.

When it comes to the final stage, one cannot avoid mentioning the phenomenon of "a brief moment of clarity before death" that many people are concerned about. The patient suddenly returns to normal from a critical point, and many think their condition is improving, but in reality, it signals that life is about to end.

In modern medicine, this "last gasp" is actually the body's self-preservation mechanism triggered after detecting a series of health crises like heart and lung failure, slow circulation, and lack of oxygen. When these emergency signals are received, the brain releases a large amount of adrenal and medullary hormones to alleviate symptoms, providing a temporary improvement.

Furthermore, the body's energy will surge, meeting the needs of all tissues and organs, allowing the patient to gradually regain vitality after exhaustion, even becoming more alert and excited. But all of this is only temporary, a brief struggle before death.

III. Why Can Some People Feel Their Death Approaching?

I often hear elderly people say that those nearing death have a "spiritual" sense that their time is near, so they begin preparing for their own funeral, and they actually pass away soon after.

Although these strange and unusual events have a superstitious element, the idea of predicting one's death day may actually have a scientific basis, especially if the body shows the following symptoms, which are warning signs. If these symptoms are detected early, there is still a chance for intervention.

1. Significant Weight Loss

A sign of physical decline is rapid weight loss. Many elderly people become frail before passing, especially in the final stages of life. Their weight continues to decrease, often due to chronic diseases, diabetes, cancer, and digestive issues. If family members do not actively monitor the diet in a short time and the patient continues to lose weight, it is important to pay attention and determine the cause. Timely intervention may still provide a chance to reverse the decline.

2. Loss of Appetite

Food is a crucial source of nutrition and energy for the human body. Therefore, a healthy person will continuously feel the need to eat to meet their nutritional needs and maintain activity. However, when appetite begins to diminish, the body gradually becomes unable to meet its nutritional needs. Over time, the body will no longer be able to sustain itself. Therefore, a loss of appetite is an important sign that the body is weakening.

3. Decreasing Quality of Life

Especially for patients who are bedridden for extended periods or unable to care for themselves, their quality of life progressively declines, making life difficult and death inevitable.

4. Increased Susceptibility to Illness

Those who frequently fall ill or who suffer from mild colds or infections that lead to serious complications and require hospitalization typically share a common trait: poor immunity. Low immunity increases the risk of infection, accelerates the process of weakening and wearing down the body, and increases the risk of death.

5. Poor Mental State

Sometimes, a person’s physical condition can be observed through their mental state, especially in the elderly. The more active elderly people are, the healthier they tend to be and the longer they live. In contrast, many elderly people experience mental decline before death.

In fact, before a person reaches the end of life, there are many uncomfortable symptoms. These symptoms act as warnings, teaching us to cherish life.