RESUMO
Objective To evaluate the levels of oxidative stress in patients undergoing long-term and repetitive exposure to hyperbaric oxygen (HBO) treatment. Methods 16 healthy volunteers and 58 patients with sub-acute sudden hearing loss (SHL) exposed to HBO were included in the study. Oxidative stress indices (malondialdehyde, MDA, advanced oxidation protein products, AOPP; superoxide dismutase, SOD) were measured in peripheral blood samples collected at the 5th,10th, 20th and 30th HBO treatments sessions (PO2 0.18 MPa, 1 session per day and 5 sessions per week) and under normal ambient pressure respectively. Results After 5th,10th, 20th and 30th sessions of HBOT, no relevant differences in these three indices were detected compared to pre-HBO exposure, between healthy volunteers (P > 0.05). Conclusions The long-term repetitive HBO treatment for 0.18 MPa of PO2 and 30 sessions could not affect in particular the response of the oxidative stress in healthy persons and patients with sub-acute SHL. The influence on three indices of patients with abnormal situation of oxidative stress undergoing lower pressure of HBO (0.18 MPa) is under investigation.