SYSTEM AND METHOD FOR PURGING MOISTURE FROM THE INFLATION APPARATUS ON AN ARTIFICIAL AIRWAY

Abstract

A system and method for periodically providing air pressure through an air line coupled to an air cuff in order to purge unwanted moisture from the air line while maintaining pressure in the air cuff. An air pressure measurement device is coupled to the air line by means of pneumatic circuit and determines whether the air pressure in the air line and coupled air cuff is equal to, greater than or less than a preprogrammed air pressure value. A pressure regulator receives the air measurement signal and is configured to control an air pressure device to increase or decrease the air pressure in the air line based upon the measured air pressure. A purge regulator controls the air pressure device to periodically cause the air pressure device to increase the air pressure in the air line to a predetermined level for a predetermined period of time at predetermined intervals in order to rid the air line of any accumulated moisture.

Claims

1. A device for purging condensation/moisture from an air line coupled to an air cuff on an artificial airway, the device comprising: a pressure measurement device, coupled to an air line which in turn is coupled to an air cuff, said pressure measurement device configured for monitoring and measuring the air pressure in said air line and coupled air cuff, and for providing a signal indicating said measured air pressure; an air pressure control device, coupled to said air line which in turn is coupled to said air cuff, said air pressure control device configured for increasing or decreasing air pressure in said air line and coupled air cuff in response to an air pressure control device control signal; a pressure regulator, configured for receiving said signal indicating said measured air pressure from said pressure measurement device and responsive to a preprogrammed air pressure value, for determining whether said measured air pressure is equal to, greater than or less than said preprogrammed air pressure value, said pressure regulator coupled to said air pressure control device and configured for providing said air pressure control device control signal, said pressure regulator further configured to be responsive to a determination that said measured air pressure is greater than said preprogrammed air pressure value, for providing a first air pressure control device control signal configured for causing said air pressure control device to decrease said air pressure in said air line and coupled air cuff, and configured to be responsive to a determination that said measured air pressure is less than said preprogrammed air pressure value, for providing a second air pressure control device control signal configured for causing said air pressure device to increase said air pressure in said air line and coupled air cuff; and an air line purge regulator device, responsive to one or more air line purge control values and coupled to said air pressure control device, and configured for providing a first air pressure control device purge control signal for causing said air pressure control device to increase said air pressure in said air line and coupled air cuff to a predetermined purge air pressure value for a predetermined period of time at predetermined intervals of time, said air line purge regulator device further configured for providing a second air pressure control device purge control signal for causing said air pressure control device to decrease said air pressure in said air line and coupled air cuff to said preprogrammed air pressure value.

2. The device of claim 1, wherein said preprogrammed air pressure value and air line purge control values are provided by user input.

3. The device of claim 1, wherein said preprogrammed air pressure value and said air line purge control values are stored in a device processor/controller.

4. The device of claim 3, wherein said device processor/controller is configured and programmed to function as both said a pressure regulator and said an air line purge regulator device.

5. The device of claim 4, wherein said device processor/controller provides said preprogrammed air pressure value to said pressure regulator and said first and second air pressure control device purge control signals to say air line purge regulator.

6. The device of claim 3, wherein said device processor/controller is responsive to said signal indicating said measured air pressure from said pressure measurement device, for providing at least one of a visual display and an audible display if said measured air pressure exceeds or is less than said preprogrammed air pressure value.

7. A device for purging condensation/moisture from an air line coupled to an air cuff on an artificial airway, the device comprising: a pressure measurement device, coupled to an air line which in turn is coupled to an air cuff, said pressure measurement device configured for monitoring and measuring the air pressure in said air line and coupled air cuff, and for providing a signal indicating said measured air pressure; an air pressure control device, coupled to said air line which in turn is coupled to said air cuff, said air pressure control device configured for increasing or decreasing air pressure in said air line and coupled air cuff in response to an air pressure control device control signal; and a device processor/controller, said device processor/controller comprising: a pressure regulator system, configured for receiving said signal indicating said measured air pressure from said pressure measurement device and responsive to a preprogrammed air pressure value, for determining whether said measured air pressure is equal to, greater than or less than said preprogrammed air pressure value, said pressure regulator system coupled to said air pressure control device and configured for providing said air pressure control device control signal, said pressure regulator system further configured to be responsive to a determination that said measured air pressure is greater than said preprogrammed air pressure value, for providing a first air pressure control device control signal configured for causing said air pressure control device to decrease said air pressure in said air line and coupled air cuff, and configured to be responsive to a determination that said measured air pressure is less than said preprogrammed air pressure value, for providing a second air pressure control device control signal configured for causing said air pressure device to increase said air pressure in said air line and coupled air cuff; and an air line purge regulator device, responsive to one or more air line purge control values and coupled to said air pressure control device, and configured for providing a first air pressure control device purge control signal for causing said air pressure control device to increase said air pressure in said air line and coupled air cuff to a predetermined purge air pressure value for a predetermined period of time at predetermined intervals of time, said air line purge regulator device further configured for providing a second air pressure control device purge control signal for causing said air pressure control device to decrease said air pressure in said air line and coupled air cuff to said preprogrammed air pressure value.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] These and other features and advantages of the present invention will be better understood by reading the following detailed description, taken together with the drawings wherein:

[0029] FIG. 1 is a schematic representation of an air line, attached to an air cuff or other inflation apparatus;

[0030] FIG. 2 is a block diagram of a device for purging an air line, attached to an air cuff or other inflation apparatus of accumulated moisture in accordance with the present invention; and

[0031] FIG. 3 is a block diagram of the air or pneumatic circuit of the device according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0032] The present invention features a device and method that provides an automatic and/or manual purge cycle in an air cuff line (pilot line) on an artificial airway to prophylactically rid the pilot balloon valve and line of any condensate, thereby keeping the communication between the air-filled cuff and the cuff pressure monitor constant. Examples of these airways would include endotracheal tubes, tracheostomy tubes, and supra-glottic airways

[0033] As shown schematically in the block diagram of FIG. 2, the device 10 of the present invention is configured either as a small standalone enclosure inside of which resides all of the hardware and software to effectuate the functionality described herein or alternatively, includes the required hardware, software and pneumatic circuitry built into a larger device. A processing device 14, such as a microprocessor or programmable logic array, is responsive to appropriate pre-programmed software instructions stored in memory (not shown but well known) to coordinate and control the operation of the device 10. Input 12 from a user in the form of keypad or other type of well-known input device input may be provided to the software processor 14 via a programming port 34. The software processor 14 controls an on board or external display 18 and/or audible or visual alarms 20. The device 10 is coupled to a cuff 4 by means of air line (pilot line) 7 coupled to the air port 54 of the device 10.

[0034] In operation, the air line 7 is coupled to a pressure measurement device 24 such as a transducer or other pressure type sensor, which measures the air pressure in the cuff 4, by means of the air port 54 coupled via a pneumatic circuit 25, and provides a signal 26 indicative of the air pressure to the microprocessor 14. The microprocessor 14 utilizes the pressure sensor signal 26 to measure the air pressure in the air line 7 and cuff 4 to determine whether the pressure is appropriate, too high or too low based on the user input 12 and/or preprogrammed values in the software process of the microprocessor 14. If the air pressure in the air line 7 and cuff 4 is as programmed, no further action is required. However, if the air pressure is too high, the microprocessor 14 provides a signal 29 to dump valve 27 which causes the air pressure device 32 to vent air from the air line 7 and cuff to ambient air. If the air pressure in air line 7 and cuff as measured by the pressure measurement device 24 is to low, the microprocessor 14 provides signal 30 to the air pump or other air pressure device 32, which causes the air pressure device 32 to increase the pressure in the air line 7 and cuff 4 providing increased air pressure in the cuff 4. The combination of the pressure measurement device/sensor 24, the air pump 32, dump valve 27 and microprocessor 14 cooperate together to provide a real time constant feedback loop and adjustment of the air pressure in the cuff 4.

[0035] One aspect of the present invention is a feature of automatically purging any moisture out of air line 7 into the cuff 4 such that accurate air pressure measurements are made. According to one aspect of the present invention, purge line control and regulation is controlled by the software controlled microprocessor or programmable logic array 14 which may include preprogrammed instructions or user programmable instructions input by means of user input 12 on programming port 34 to control this feature. At predetermined time intervals, the microprocessor 14 causes the air pressure pump/device 32 to impart a predetermined amount of pressure on air line 7 for a predetermined period of time in order to purge any moisture from within the air line 7. Any accumulated moisture in the air line 7 is pushed into the cuff 4. The appropriate pressure in the cuff 4 is maintained utilizing the pressure measurement sensor 24 and dump valve 27 to make sure that the appropriate amount of pressure for the appropriate amount of time is maintained on the air line 7. Once the air pressure has been maintained for the predetermined period of time, microprocessor 14 activates the dump valve 27 to release the increased pressure from air line 7 and cuff 4 thereafter maintaining the standard desired air pressure.

[0036] The invention is, in one embodiment, a stand-alone monitor that is preferably equipped with an integrated USB 63 port and alarms 20, as well as a power system 39 including a rechargeable battery backup 43, AC wall power source 42, and power manager and battery charger 44 all working together to provide system power 40. The monitor of the invention is used in conjunction with a disposable, single-patient use tubing set, which is connected to the artificial airway at the pilot balloon. In another embodiment, the present invention can be integrated into another device such as a ventilator or anesthesia machine. Additional inputs such as a head of bed position sensor 60, time of day and date clock 36, and battery gas gauge 38 may be provided.

[0037] To prevent the unwanted effects of undesirable cuff pressures, the invention checks the cuff pressure every millisecond; and any time its pressure sensor 24 notes a drop in pressure of more than 2 cmH2O from the set point, it will immediately entrain room air into the cuff 4 to bring it to within +/2cmH2O of the set point. In the event that the set point cannot be achieved within 30 seconds (i.e.; a massive leak) an alarm will sound.

[0038] If the transducer sensor 24 notes an increase in pressure of more than 2 cm H2O around the set point that persists for at least 45 seconds, it will vent to room air to bring the cuff pressure back to +/2 cmH2O by activating dump valve 27. If a high pressure condition cannot be resolved within 2 minutes, an alarm will sound to notify the clinician.

[0039] The invention also includes an automatic line purge cycle to prophylactically rid the pilot balloon, valve and line 7 of any condensate, thereby keeping the communication between the air-filled cuff 4 and the cuff pressure monitor 10 constant. For example, the preferred embodiment contemplates that every 30 minutes, the device according to the present invention will deliver 85 cm H2O for 25 seconds, which will push any humidification or moisture from the pilot line 7 line into the cuff 4, where it will not interfere with cuff pressure readings. 85 cm H2O is believed to be the lowest pressure that will effectively clear the pilot line 7 in a short time period however higher or lower purge pressures and longer or shorter times are potentially contemplated and within the scope of the present invention. In the unlikely event that this automatic purge is unsuccessful, the clinician can also press the Inflate key to trigger a manual purge cycle or may otherwise initiate a manual purge cycle.

[0040] The present invention will automatically bring the cuff pressure back to +/2 cm H2O around the set point after the 25 seconds purge cycle; essentially immediately after the purge cycle completes. It is as yet undetermined whether or not this frequency of purge cycle will be adequate to keep the line free of condensate to ensure accurate cuff pressure readings. The belief is that every half hour should be sufficient, but actual clinical use will provide useful data in this regard.

[0041] Accordingly, the present invention provides a system and method for maintaining air pressure within the air cuff on an artificial airway while also providing a system and method for purging the air line between the controller and the artificial airway cuff to assure accurate readings of air pressure within the cuff. Modifications and substitutions by one of ordinary skill in the art are considered to be within the scope of the present invention, which is not to be limited except by the allowed claims and their legal equivalents.