Changes in vasomotion--effect of hyperbaric oxygen in patients with diabetes Type 2.

OBJECTIVES: To investigate vasomotion in diabetic patients who underwent sessions of hyperbaric oxygen (HBO2) therapy. MATERIALS AND METHODS: Seventy-one patients with diabetes Type 2 and lower-extremity neuropathy were enrolled in a prospective matched case-control study. A total of 39 patients underwent 15 sessions of HBO2 therapy consisting of 90 minutes of breathing 100% oxygen at 2.5 atmospheres; 32 were included in the control group without exposure to hyperbaric oxygen. We used laser Doppler flowmetry for measurement of flowmotion. Spectral analysis of laser Doppler flowmetry signals was performed using the Fast Fourier transform algorithm. The total spectral activity was divided into the subgroup of endothelium, adrenergic, intrinsic smooth muscle, respiratory and cardiac spectral activity. The lateral ankle and the dorsum of the foot were chosen for this study. Heating provocation test was performed on both sites. The measurement was performed 24 hours before the first HBO2 session and 24 hours after the last (15th) session of therapy. RESULTS: We observed a significant increase in respiratory, cardiac and total spectral activity of flowmotion on the ankle as well as a significant increase in cardiac and total spectral activity on the dorsum of the foot in patients without a foot ulcer. In the subgroup of patients with a diabetic ulcer, a decrease of total spectral activity of flowmotion on the dorsum of the foot was observed. CONCLUSION: Flowmotion (indirectly vasomotion) measured by laser Doppler flowmetry changed significantly after HBO2 therapy. Flowmotion dynamics may partly explain the positive effect of HBO2 on the healing process of a diabetic ulcer.

Effect of hyperbaric oxygen on lipoprotein subfractions in diabetic patients.

OBJECTIVES: Favorable metabolic changes have been observed in many in vitro and animal studies after application of hyperbaric oxygen (HBO2). Metabolic changes after hyperbaric oxygen therapy, especially focused on lipoprotein subfractions, have not been described in humans. Our aim was to investigate possible alteration in concentration of lipoprotein subfractions in diabetic patients after hyperbaric oxygen therapy. METHODS: 58 Type 2 diabetic patients were enrolled in a prospective matched case-control study. A total of 31 underwent hyperbaric oxygen therapy, and 27 were included in the control group without HBO2 exposure. Fasting concentrations of lipoprotein subfractions were measured by electrophoresis in polyacrylamide gel 24 hours before and 24 hours after hyperbaric sessions performed at 2.5 atmospheres absolute for 15 days. Homeostatic model assessment of insulin resistance, C-peptide and glycemic variability were assessed before and after therapy. RESULTS: We observed decreased subfractions of very-low-density lipoprotein (VLDL), intermediate-density lipoprotein (IDL 3), LDL 1, LDL 2 and LDL 3-7 after hyperbaric oxygen treatment. In addition, the IDL 1 subfraction, as well as the concentration of C-peptide, increased significantly in the treatment arm. Glycemic variability improved after therapy. No differences were observed in the control group. CONCLUSION: Hyperbaric oxygen therapy is connected with antiatherogenic metabolic changes. This study demonstrates that hyperbaric oxygen therapy may hold potential for inducing metabolic changes in diabetic patients that may decrease their cardiovascular risk.