Serbest dalgiclarda iYKAS ile serebrovaskuler reaktivite olcumu

Effect of consecutive maximal dry breath-holds was compared between two groups of free divers with different experience levels and a control group. Hemoglobin concentration ([Hb], by functional near infrared spectroscopy, fNIRS), heart rate and systemic oxygen saturation (SO2, by pulse oxymetry) measurements were performed during four consecutive maximal dry breath-holdsChange in [Hb] (Δ[Hb]), change in SO2 (ΔSO2) and breath-hold indices (BHI_Δ[Hb], BHI_ΔSO2) normalized to hold durations calculated for each breath-hold. Analyses over these indices showed statistical difference between groups (p≪5×10−5 for both indices). Free diver groups exhibited a higher slope of increase of the indices among consecutive breath holds compared to the control group elucidating an enhanced reactivity to hypoxia. Our results indicate that cerebrovascular reactivity to hypercapnia can be learned and trained and the level of reactivity can be reliably quantified by fNIRS.