Neurogenic shock

Neurogenic shock
Classification and external resources
Cervical spine MRI of a patient with SCI: C4 fracture and dislocation, spinal cord compression
ICD-10	R57.8
ICD-9	785
MeSH	D012769

Neurogenic shock is a distributive type of shock resulting in hypotension, occasionally with bradycardia, that is attributed to the disruption of the autonomic pathways within the spinal cord. Hypotension occurs due to decreased systemic vascular resistance resulting in pooling of blood within the extremities lacking sympathetic tone. Bradycardia results from unopposed vagal activity and has been found to be exacerbated by hypoxia and endobronchial suction.^[1] Neurogenic shock can be a potentially devastating complication, leading to organ dysfunction and death if not promptly recognized and treated. It is not to be confused with spinal shock, which is not circulatory in nature.

Causes

Neurogenic shock can result from severe central nervous system damage (brain injury, cervical or high thoracic spinal cord).^[2] In more simple terms: the trauma causes a sudden loss of background sympathetic stimulation to the blood vessels. This causes them to relax (vasodilation)^[3] resulting in a sudden decrease in blood pressure (secondary to a decrease in peripheral vascular resistance)

Treatment

• Fluid is always the initial treatment of shock, especially since concomitant hemorrhagic shock must be excluded following trauma. Most institutions will additionally utilize pressor agents to achieve hemodynamic stability.
• Dopamine (Intropin) is often used either alone or in combination with other inotropic agents.
• Vasopressin (antidiuretic hormone [ADH])^[4]
• Certain vasopressors (ephedrine, norepinephrine). Phenylephrine may be used as a first line treatment, or secondarily in patients who do not respond adequately to dopamine.
• Atropine (administer if bradycardia is severe.)

References