Neurogenic Shock vs. Spinal Shock

Spinal Cord Injury Patients

This article discusses the two types of shock associated with spinal cord injuries:

1. Neurogenic shock
2. Spinal shock

Both neurogenic shock and spinal shock can occur in patients who have experienced a spinal cord injury. However, these are two distinct conditions.

The two conditions can be easily distinguished because neurogenic shock affects the entire nervous system, whereas spinal shock only affects the spinal cord. These conditions are discussed in detail below.

Related Video – What Do You Do for a Spinal Injury?

Neurogenic Shock is a High-Level Injury

With neurogenic shock, the spinal cord injury is typically a very high-level injury, usually above the thoracic 6 (T6) level. T6 is the “magic number” that places spinal cord injury patients at risk for complications.

T6 is located in the thoracic vertebrae.

The spinal cord is the body’s information highway. It relays messages and input from the periphery to the brain, and then sends a response from the brain back to the muscles and tissues in the periphery.

In neurogenic shock, there is a disruption of the sympathetic nervous system (SNS) messages being relayed from T1 to L2.

Essentially, there is a loss of SNS stimulation. That loss of stimulation includes the loss of the fight or flight hormones, such as epinephrine and norepinephrine, which are also known as catecholamines.

Epinephrine and norepinephrine are catecholamines that increase heart rate and blood pressure.

The catecholamines are powerful vasoconstrictors and have positive chronotropic effects, meaning they increase the heart rate. When epinephrine and norepinephrine are lost, patients will experience:

• Significant bradycardia or decreased heart rate.
• Hypotension due to vasodilation.

Bradycardia and hypotension are the two primary symptoms of neurogenic shock.

Read: The Neurological Assessment

Nursing Assessments

With neurogenic shock, the provider’s priority is to maintain the airway, breathing, and circulation (ABCs). The provider must focus on maintaining blood pressure because these patients will experience massive vasodilation and bradycardia. 

Bradycardia is treated with atropine, while hypotension is treated with fluids. For patients with spinal cord injury, a goal of care is to maintain the mean arterial pressure (MAP) above 80–85 mm Hg. In addition, the provider needs to be aware of cervical spine precautions.

Neurogenic shock and spinal shock differ in their pathophysiology.

Related Video – What is the Neurological Assessment?

Spinal Shock Affects the Spinal Cord

It is important to understand how the two types of spinal injuries affect the spinal cord, keeping in mind that in spinal shock, only the spinal cord is affected. 

When a patient presents with a spinal cord injury, regardless of the location along the spinal cord, there will likely be bleeding and inflammation at the site of the injury. That bleeding and inflammation impacts surrounding tissue, and that damaged tissue releases chemical mediators. Those chemical mediators cause potent vasoconstriction.

The tissue damage, inflammation, and vasoconstriction result in spinal cord ischemia and hypoxia. A spinal cord that is not receiving blood flow and is not oxygenated is not going to do its job properly. That results in paralysis and loss of sensation below the level of the injury.

Tissue damage, inflammation, and vasoconstriction are present in a spinal cord injury.

Depending on the type of spinal cord injury, the patient may regain movement and sensation. If the patient had an injury involving a complete transection of the spinal cord, they will unfortunately not regain movement and sensation. However, if the patient had a compression of the spinal cord, they will regain movement and sensation below the level of injury once the inflammation and bleeding are controlled.

There are two types of spinal cord injuries, which impact the patient in distinct ways. In neurogenic shock, the entire nervous system is affected, whereas, in spinal shock, only the spinal cord is affected. The provider needs to distinguish between these types of injuries to determine the best course of action.