When can adaptive servo ventilation be considered during a titration study?

Adaptive servo ventilation (ASV) is a mode of non-invasive ventilation that is particularly effective for patients experiencing Cheyne-Stokes respiration and central sleep apneas. During a titration study, it is essential to evaluate how well the current therapy is managing the patient's specific respiratory events.

When a down titration has failed to resolve issues like Cheyne-Stokes respiration or central emergent apneas, ASV can be considered as it is designed to automatically adjust pressure based on the patient's breathing patterns, potentially improving their condition. This scenario indicates that the existing interventions are insufficient, making ASV a viable alternative to better manage the patient's respiratory issues during sleep.

The other options do not align with the appropriate application of ASV during a titration study. For instance, resolving hypopneas or considering a history of asthma does not directly relate to the need or timing for ASV application. Additionally, waiting for a second titration study before considering ASV can delay essential treatment for patients who require immediate interventions for their respiratory disturbances.