Automated control for detection of flow limitation

US9358353B2 · kind B2 · utility

Assignee

• ResMed Corp. · AU

Inventors

• Jeffrey Peter Armitstead · Fawn Drive, AU
• Peter Edward Bateman · Sydney, AU
• David John Bassin · Sydney, AU

Key dates

• Filing date: May 9, 2008
• Grant date: Jun 7, 2016
• Expiry date: Feb 8, 2032

Classification

• Technology area (CPC A): Human Necessities
• CPC primary: A61M2230/40
• WIPO field: Medical technology
• WIPO sector: Instruments

Abstract

A respiratory flow limitation detection device, which can include an airway pressure treatment generator, determines a flow limitation measure (506) based one or more shape indices for detecting partial obstruction and a measure of a patient's ventilation or respiratory duty cycle. The shape indices may be based on function(s) that ascertain the likelihood of the presence of M-shaped breathing patterns and/or chair-shaped breathing patterns. The measure of ventilation may be based on analysis of current and prior tidal volumes to detect a less than normal patient ventilation. The duty cycle measure may be a ratio of current and prior measures of inspiratory time to respiratory cycle time to detect an increase in the patient's inspiratory cycle time relative to the respiratory cycle time. A pressure setting based on the flow limitation may then be used to adjust the treatment pressure to ameliorate the patient's detected flow limitation condition.