Flow therapy system and method

Abstract

A method of determining a duration of safe apnoea. Information is obtained relating to a respiratory indicator, and a duration of safe apnoea is determined from the obtained information. A respiratory therapy system has one or more patient interfaces. A processor is configured to determine a duration of safe apnoea based on obtained information relating to a respiratory indicator.

1 . A respiratory therapy system comprising :
 one or more patient interfaces; and   a processor configured to determine a duration of safe apnoea from a measured indicator.   
     
     
         2 . The system of  claim 1 , wherein the indicator is one or more of a respiratory indicator and/or a physiological indicator. 
     
     
         3 . The system as of  claim 1 , wherein the indicator comprises, or is based on, carbon dioxide concentration, carbon dioxide clearance, respiratory rate, oxygen concentration, arterial oxygen, arterial carbon dioxide content, lung volume, lung compliance, lung/airway pressure, airway resistance/patency, V/Q mismatch (ventilation (V) - perfusion (Q)), heart rate, blood pressure, or metabolic rate. 
     
     
         4 . The system of  claim 1 , wherein the processor is configured to determine the duration of safe apnoea from a plurality of indicators comprising, or based on, two or more of carbon dioxide concentration, carbon dioxide clearance, respiratory rate, oxygen concentration, arterial oxygen, arterial carbon dioxide content, lung volume, lung compliance, lung/airway pressure, airway resistance/patency, V/Q mismatch (ventilation (V) - perfusion (Q)), heart rate, blood pressure, or metabolic rate. 
     
     
         5 . The system of  claim 4 , wherein the processor is configured to determine an average duration of safe apnoea from the plurality of measured indicators. 
     
     
         6 . The system of  claim 4 , wherein the processor is configured to determine a plurality of durations of safe apnoea from the plurality of measured indicators and further wherein the processor selects the shortest duration of safe apnoea from the plurality of durations of safe apnoea. 
     
     
         7 . The system of  claim 1 , wherein the processor is configured to compare or fit a model to the respiratory indicator determine the duration of safe apnoea. 
     
     
         8 . (canceled) 
     
     
         9 . (canceled) 
     
     
         10 . (canceled) 
     
     
         11 . (canceled) 
     
     
         12 . (canceled) 
     
     
         13 . The system of  claim 1 , wherein the system is configured to measure oxygen concentration as an indicator. 
     
     
         14 . The system  claim 13 , wherein the oxygen concentration is measured based on expired oxygen, transcutaneous oxygen, blood gases, haemoglobin oxygen concentration, blood pressure, arterial partial pressure of oxygen, or arterial oxygen content. 
     
     
         15 . The system  claim 14 , wherein the processor is configured to determine the duration of safe apnoea based on a threshold arterial partial pressure of oxygen (PaO2). 
     
     
         16 . The system  claim 15 , wherein the threshold arterial oxygen content is determined from a threshold haemoglobin oxygen saturation (SpO2). 
     
     
         17 . The system  claim 16 , comprising a user interface to enable a user to input the threshold haemoglobin oxygen saturation (SpO2), or threshold arterial partial pressure of oxygen (PaO2). 
     
     
         18 . The system  claim 16 , wherein threshold haemoglobin oxygen saturation (SpO2), or threshold arterial partial pressure of oxygen (PaO2) is a predetermined value. 
     
     
         19 . The system of  claim 14 , wherein the processor is configured to determine the duration of safe apnoea based on, a length of time until the arterial partial pressure of oxygen reaches the threshold arterial partial pressure of oxygen. 
     
     
         20 . The system  claim 19 , wherein the length of time until the arterial partial pressure of oxygen reaches the threshold arterial partial pressure of oxygen is determined by the processor by measuring or estimating a rate of change of arterial partial pressure of oxygen. 
     
     
         21 - 39 . (canceled) 
     
     
         40 . The system of  claim 1 , wherein at least one of the one or more patient interfaces is non-sealing. 
     
     
         41 . The system of  claim 1 , wherein the at least one of the one or more patient interfaces is a nasal cannula. 
     
     
         42 . The system of  claim 1 , further comprising a humidifier for providing humidified gases. 
     
     
         43 . The system of  claim 1 , wherein the system is configured to deliver gases to a patient at a flow rate greater than 15 L/min. 
     
     
         44 . The system of  claim 1 , wherein the system provides high flow respiratory support.