Characterization of the spectrum of hemodynamic profiles in trauma patients with acute neurogenic shock.

OBJECTIVE: Neurogenic shock considered a distributive type of shock secondary to loss of sympathetic outflow to the peripheral vasculature. In this study, we examine the hemodynamic profiles of a series of trauma patients with a diagnosis of neurogenic shock.

METHODS: Hemodynamic data were collected on a series of trauma patients determined to have spinal cord injuries with neurogenic shock. A well-established integrated computer model of human physiology was used to analyze and categorize the hemodynamic profiles from a system analysis perspective. A differentiation between these categories was presented as the percent of total patients.

RESULTS: Of the 9 patients with traumatic neurogenic shock, the etiology of shock was decrease in peripheral vascular resistance (PVR) in 3 (33%; 95% confidence interval, 12%-65%), loss of vascular capacitance in 2 (22%; 6%-55%) and mixed peripheral resistance and capacitance responsible in 3 (33%; 12%-65%), and purely cardiac in 1 (11%; 3%-48%). The markers of sympathetic outflow had no correlation to any of the elements in the patients' hemodynamic profiles.

CONCLUSIONS: Results from this study suggest that hypotension of neurogenic shock can have multiple mechanistic etiologies and represents a spectrum of hemodynamic profiles. This understanding is important for the treatment decisions in managing these patients.