Decompression sickness

Hippokratia 2000, 4(1):14-18

Th. Mesimeris


Decompression sickness (DCS) is due to formation of air bubbles in tissues and blood, following rapid reduction of the environmental pressure. DCS includes every clinical syndrome following inadequate decompression. Type I DCS is characterized by mild clinical symptoms such as limb pain, lymphatic and cutaneous manifestations. Type II DCS is characterized by severe neurological and cardiorespiratory symptoms or even shock, and can sometimes be fatal. Arterial gaseous embolism, following pulmonary overinflation, is the most serious diving accident and is considered as type III of DCS. Intravascular air bubbles interact with endothelium and blood constituents, leading to a) increased capillary permeability, extravasation and hemoconcentration, b) activation of the coagulation cascade and DIC (disseminated intravascular coagulation) and c) denaturation of plasma proteins. These alterations result in serious impairment of the microcirculation and severe ischemic tissue damage. The treatment of DCS consists of recompression in a hyperbaric chamber, in order to minimize air bubble size through the increased ambient pressure and hyperbaric oxygenation of the cells. An equally important goal of the treatment of the DCS is the restoration of the intravascular fluid volume and the rheological properties of blood.