Effect of carbogen inhalation on peripheral tissue perfusion and oxygenation in patients suffering from sudden hearing loss

The effects of repeated carbogen inhalation on peripheral tissue perfusion and oxygenation were assessed in 5 patients suffering from sudden hearing l oss by means of continuously measured subcutaneous tissue oxygen and carbon dioxide tension, transcutaneous oxygen tension, laser Doppler red cell flu x, and fingertip temperature. The subcutaneous oxygen tension increased cle arly during the carbogen inhalation periods, and also, a smaller increase i n subcutaneous carbon dioxide tension was simultaneously noticed. The chang es in transcutaneous oxygen tension were even greater and the latency was s horter as compared with the subcutaneous gas tensions. The laser Doppler me asurements showed no signs of vasoconstriction during the study. In conclus ion, carbogen inhalation increases peripheral tissue oxygenation without mi crovascular vasoconstriction and with only a minor retention of carbon diox ide.