A patient presents to the ED with the chief complaint of falling off of a horse. The HCP suspects a spinal cord injury. You know this puts the patient at risk of neurogenic shock. What is one of the processes occurring in neurogenic shock?

Choice A rationale Neurogenic shock occurs when a spinal cord injury disrupts the autonomic nervous system's ability to transmit signals. This leads to a loss of sympathetic vasomotor tone, resulting in massive vasodilation. Without the ability to constrict vessels, blood pools in the periphery, and blood pressure drops significantly. Unlike other forms of shock, the heart rate often remains low because the sympathetic boost is missing. Normal vascular tone is maintained by constant signals from the brainstem. Choice B rationale An infection progressing to the blood describes septic shock, not neurogenic shock. While a patient with a spinal cord injury might eventually develop a urinary tract infection or pneumonia, the immediate cause of shock following a fall and spinal trauma is neurological. Sepsis involves a systemic inflammatory response to pathogens, whereas neurogenic shock is a hemodynamic failure due to the loss of nervous system control over the blood vessels and the heart. Choice C rationale In neurogenic shock, the baroreceptors are unable to compensate effectively because the neural pathways to increase systemic vascular resistance are severed or blocked. Normally, baroreceptors sense low pressure and trigger the sympathetic nervous system to increase the heart rate and constrict vessels. In this condition, that feedback loop is broken. Instead of an increase in resistance, the patient experiences a profound decrease in systemic vascular resistance, leading to distributive shock. Choice D rationale This choice mentions absolute hypovolemia, which refers to a physical loss of fluid, and relative hypovolemia, which refers to fluid displacement. Neurogenic shock primarily involves relative hypovolemia because the total volume of blood is still in the body, but the vastly dilated vessels make it insufficient to fill the space. There is no inherent absolute loss of blood unless the patient has a concurrent injury causing hemorrhage. Neurogenic shock is purely a distribution and tone problem.