NEUROGENIC SHOCK: SYMPTOMS, CAUSES, TREATMENT - MEDICINE - 2024

The neurogenic shock or neurogenic shock is a condition in which there is insufficient blood flow in the body due to sudden loss signals the sympathetic nervous system responsible for maintaining normal muscle tone in the blood vessel walls.

When neurogenic shock occurs, the blood vessels relax and dilate, leading to the accumulation of blood in the venous system and a general decrease in blood pressure.

This may be due to a complication from injury to the brain or spinal cord, particularly in the T6 region and where there was a disconnect between the brain and the autonomic nervous system.

It is a life-threatening condition that requires immediate medical attention to prevent irreversible tissue damage or even death of the patient. There are several types of shocks, however, the neurogenic is considered the most difficult to handle due to possible irreversible tissue damage.

Neurogenic shock should not be confused with spinal shock, since the latter has a duration ranging from one day to a couple of days, and the absence of sensory and motor tone is temporary as well. Neurogenic shock, in contrast, lasts for several days to a few weeks and can result in loss of muscle tone.

Neurogenic shock symptoms

Decreased blood pressure

Hypotension or low blood pressure as a consequence of a reduction in systemic vascular resistance translated into the collection of blood within the extremities, resulting in a deficiency in sympathetic tone.

Injury to the spinal cord generally results in the inability of the blood vessels to contract, and in response to the alteration of the autonomic nervous system, there is a decrease in blood pressure.

Hypothermia

Hypothermia is an excessive drop in body temperature in which the patient has warm limbs and the rest of the body cold to the touch. This feature can be a symptom of neurogenic shock.

It occurs because generally the injury to the spinal cord results from the loss of sympathetic tone, which in turn can end in the inability to redirect blood flow to the circulation of the nucleus, causing excessive loss in body temperature.

Bradycardia

Bradycardia is one of the key signs of neurogenic shock, characterized by a resting heart rate of less than 60 beats per minute.

This is because the spinal cord injury causes nerve damage, which in turn causes the walls of the blood vessels to relax and slows the heart rate.

Bradycardia is also aggravated by hypoxia or insufficient blood supply.

Other symptoms of shock include: shallow and rapid or difficult breathing, pale appearance of the skin, cold and clammy skin, dizziness and lightheadedness, nausea and vomiting, fainting, fast and weak pulse.

In the severe state of neurogenic shock, symptoms may also be accompanied by:

• change in mental state or confusion and disorientation
• anxiety
• blank stares or eyes staring at nothing
• no response to stimuli
• low or no amount of urine
• excessive sweating
• bluish discoloration of the lips and fingers (signifying oxygen deprivation in the body)
• significant chest pain
• unconsciousness.

Causes

Neurogenic shock occurs immediately after a spinal cord injury, which is why this injury is the main cause of neurogenic shock.

Spinal cord injury can occur with complete or incomplete bone marrow damage, which is why it is defined as injury to any part of the spinal cord, including the nerves at the end of the spinal canal.

Spinal cord injuries or trauma can be blunt (blunt) or penetrating. They can be caused by dislocation, rotation, and over extension or flexion of the cord. It can also occur as a result of sports injuries, falls, vehicle accidents, gunshot wounds, stab wounds, among others.

In some cases, it can occur as a result of local anesthesia being administered incorrectly. Drugs and medications that affect the autonomic nervous system can also result in neurogenic shock.

Treatment

Neurogenic shock is a life-threatening situation, which is why it is considered a medical emergency in order to preserve the life of the patient.

Immobilization of the spine is necessary to prevent further damage to the spinal cord.

-The admission to the nearest hospital is necessary to ensure the preservation of life. The goal of emergency physicians will be to stabilize the patient and prevent any irreversible tissue damage.

-For blood pressure, the patient must receive the administration of intravenous fluids in order to restore the values. Dopamine and other inotropic agents can be infused if fluid resuscitation is insufficient.

-For severe bradycardia, atropine or a pacemaker is usually given if necessary.

-In the event that there has already been a neurological deficit, the high dose of methylprednisolone can be administered within eight hours of the onset of neurogenic shock.

Spinal cord

The spinal cord is a long cylinder of nerves that runs from the base of the brain through the spinal canal and down the spinal column. In adults it is about 45 centimeters long and 2 centimeters in diameter.

It is part of the central nervous system (CNS) along with the brain. It has different segments and each contains a pair of roots made of nerve fibers called the dorsal (towards the back) and ventral (away from the back) roots.

What is the function of the spinal cord?

Its main functions are:

Electrical communication

These electrical signals are conducted up and down the cord, allowing communication between different sections of the body and with the brain, as the cord passes through different levels of the trunk section.

Walking (locomotion)

During gait, various muscle groups in the legs coordinate to contract over and over again.

Although it may seem simple, putting one foot in front of the other while walking has to be carefully coordinated by various groups of neurons known as central pattern generators in the spinal cord, which send signals to the leg muscles. This allows them to extend or contract, producing the alternate movements that are involved in walking.

Reflexes

Reflexes are predictable and involuntary responses of the spinal cord and the nerves of the peripheral nervous system (PNS).

References

1. John P. Cunha (2016). Medical Definition of Neurogenic Shock. Medicine Net. Recovered from: medicinenet.com.
2. Elizabeth H. Mack (2013). Neurogenic Shock. The Open Pediatric Medicine Journal. Recovered from: benthamopen.com.
3. Medicalmd (2014). Neurogenic Shock. HubPages. Recovered from:
4. Dudek RW (2014). Embryology. Lippincott Williams & Wilkins. Recovered from: myvmc.com.