Real-Time Dynamic Carbon Dioxide Administration: A Novel Treatment Strategy for Stabilization of Periodic Breathing With Potential Application to Central Sleep Apnea

Objectives tudy targeted carbon dioxide (CO2) oscillations seen in oscillatory ventilation with dynamic pre-emptive CO2 administration. ound ations in end-tidal CO2 (et-CO2) drive the ventilatory oscillations of periodic breathing (PB) and central sleep apnea in heart failure (HF). s healthy volunteers simulated PB, while undergoing dynamic CO2 administration delivered by an automated algorithm at different concentrations and phases within the PB cycle. The algorithm was then tested in 7 patients with HF and PB. s untary PB, the greatest reduction (74%, p < 0.0001) in et-CO2 oscillations was achieved when dynamic CO2 was delivered at hyperventilation; when delivered at the opposite phase, the amplitude of et-CO2 oscillations increased (35%, p = 0.001). In HF patients, oscillations in et-CO2 were reduced by 43% and ventilatory oscillations by 68% (both p < 0.05). During dynamic CO2 administration, mean et-CO2 and ventilation levels remained unchanged. Static CO2 (2%, constant flow) administration also attenuated spontaneous PB in HF patients (p = 0.02) but increased mean et-CO2 (p = 0.03) and ventilation (by 45%, p = 0.03). sions c CO2 administration, delivered at an appropriate time during PB, can almost eliminate oscillations in et-CO2 and ventilation. This dynamic approach might be developed to treat central sleep apnea, as well as minimizing undesirable increases in et-CO2 and ventilation.