Tissue expansion and skin circulation. Simultaneous monitoring by laser Doppler flowmetry and transcutaneous oximetry.

The skin circulation was examined in nine patients during filling of their breast expander prostheses. Despite the high expansion pressure, which was increased above the systolic blood pressure, the overlying skin showed good circulation both clinically and when measured with a laser Doppler flowmeter and a transcutaneous oximeter. We conclude that the expansion was therefore directed to the tissues between the expander and the skin--that is, the fibrous capsule surrounding the prosthesis. Nine subcutaneous tissue expanders located in different anatomical regions were overfilled to a pressure at which all skin circulation ceased. Sufficient saline was then removed to allow skin circulation to return. Oxygenation of the skin ceased at a relatively low pressure when measured by transcutaneous oximetry, whereas when the skin circulation was measured with a laser Doppler flowmeter it did not disappear until the expander pressure had been raised appreciably above that level.