[Changes in the pharyngeal bacterial flora during hyperbaric oxygenation]

Qualitative and quantitative bacteriological tests of throat smears were carried out on the following three groups of patients: 1) Patients exposed to several 90-minute sequences of oxygen hyperbaria, at a height of 2.2 ata O2, at intervals of 2 to 3 days. 2) Patients exposed to a single 30-minute dose of oxygen hyperbaria at a height of 2.5 ata O2/the oxygen test. 3) Patients who had never been exposed to oxygen hyperbaria. Several hundred bacterials strains of the Streptococcus, Staphylococcus, Klebsiella and Nocardia genus were isolated from the material collected from the tested patients over intervals of a few days. The collected samples were when subjected to a detailed bacteriological analysis. At the same time bacteriological tests were performed at intervals on the hyperbaric atmosphere of the therapeutic pressure chamber, the walls of the chamber, and the masks used by the patients during the administration of hyperbaric oxygen. A certain degree of qualitative and quantitative changes (number reduction of bacterial strains) was observed. The authors attribute these results to the influence of hyperbaric oxygenation both on the microorganisms, as well as on a given patient's reactivity.