Gas tension and pH in middle ear effusion.

The composition of gases and the gas tension in middle ear effusion in patients with serous otitis media have been investigated. By using a specially designed micro-method, very small amounts of middle ear fluid could be analyzed. The effusion was obtained by puncturing the air cells of the mastoid process. The average value of P-O2 was 41 mm Hg; Pco2 was 58 mm Hg, pH 7.24. The possible mechanism for the impaired perfusion of the mucous membranes is discussed as well as some clinical consequences.