Patent ID: 7967012
Filing Date: 2011-06-28
Classification: A61M

Abstract:
1. Apparatus for the treatment of cardiac failure, Cheyne-Stokes breathing or central sleep apnea, comprising: a controllable source of breathable gas at positive pressure; means for delivering said breathable gas at positive pressure to a subject's airway; means for deriving a measure of respiratory airflow of the subject; and a servo-controller accepting an input variable and a reference quantity, and producing an output that is used to bring the value of the input variable towards the value of the reference quantity; characterised in that: (i) said input variable is a measure of instantaneous ventilation, and (ii) said reference quantity is a percentage of a long-term measure of ventilation continuously derived from said measure of respiratory airflow, wherein said percentage is smaller than a value that will result in positive feedback and larger than one that will permit residual Cheyne-Stokes breathing, and said long-term is a timescale longer than that of the waxing-waning cycle of untreated Cheyne-Stokes breathing or central sleep apnea.