Tracheal tube cuff inflation control and monitoring system

An inflation control system comprising:

• a cuff inflation line configured for sealed, fluidic interconnection with an inflatable cuff of a tracheal tube;
• an assembly having an exhaust port vented to atmosphere, said assembly configured for sealed, fluidic interconnection in series with said cuff inflation line and a source of gas at a pressure greater than atmospheric pressure, wherein in a first state of said assembly said cuff inflation line is coupled to said source of gas to deliver volume into said cuff inflation line, and wherein in a second state of said assembly said cuff inflation line is coupled to said exhaust port of said assembly to deliver volume out of said cuff inflation line;
• a system for detecting net volume entering said cuff inflation line by evaluating volume into said cuff inflation line and volume out of said cuff inflation line;
• and
• an alarm indicating a cuff leak in response to said system detecting net volume entering said cuff inflation line.

A cuff inflation method comprising:

• providing a tracheal tube having an inflatable cuff and inspiratory tubing;
• providing a source of pressurized gas;
• providing a high pressure relief valve and a low pressure relief valve, each of said relief valves having an inlet port, an outlet port, and a valved exhaust port;
• connecting said inlet and outlet ports of said high pressure relief valve and said low pressure relief valve in series with said source of pressurized gas and said inflatable cuff of said tracheal tube;
• supplying pressurized gas from said source of gas to said inflatable cuff through said high pressure relief valve and said low pressure relief valve;
• and
• opening said valved exhaust port of said low pressure relief valve in response to both pressure in said inflatable cuff and pressure in said inspiratory tubing of said tracheal tube.

A cuff inflation method comprising the steps of:

• providing a tracheal tube having an inflatable cuff;
• supplying gas to said inflatable cuff of said tracheal tube when pressure in said inflatable cuff is below a first predetermined level and pressure in said tracheal tube is above a second predetermined level;
• and
• removing gas from said inflatable cuff when pressure in said inflatable cuff is above a third predetermined level and pressure in said tracheal tube is below said second predetermined level, wherein said third predetermined level is less than said first predetermined level.

A respiration system comprising:

• a tracheal tube having an inflatable cuff and inspiratory tubing;
• an adjustable high pressure relief valve and an adjustable low pressure relief valve, both of which have inlet and outlet ports configured for sealed, fluidic interconnection in series with a source of pressurized gas and said inflatable cuff of said tracheal tube, both of which also have valved exhaust ports urged toward the closed condition;
• a solenoid mounted in series with the exhaust port of the low pressure relief valve, said solenoid arranged to block the exhaust port when said solenoid is activated;
• a pressure transducer in sealed, fluidic communication with said inspiratory tubing of said tracheal tube to monitor pressure within said inspiratory tubing, said pressure transducer generating an electrical output responsive to inspiratory tubing pressure;
• and
• a threshold control circuit responsive to said electrical output of said pressure transducer for activating said solenoid.