Neurohemodynamics of Pulmonary Edema

The authors criticize the concept of "neurogenic pulmonary edema" as resulting from an increase in pulmonary capillary permeability mediated by nerve impulses to those vessels. They show that one of the methods used to produce "neurogenic pulmonary edema" markedly elevates systemic and pulmonary vascular pressures, the latter to levels high enough to produce pulmonary edema. Vagotomy and/or upper thoracic sympathectomy do not prevent the elevation of pulmonary vascular pressures. Blockade of the sympathetic innervation to the systemic vascular bed lowers the systemic vascular pressures and brings the pulmonary vascular pressures back to normal. The control of pulmonary vascular pressures by sympathetic impulses to the systemic vascular bed is demonstrated.