High frequency chest wall oscillation air pulse generator having pressure sensor for feedback control
A high frequency chest wall oscillation therapy system includes an air pulse generator. The air pulse generator includes control circuitry and a fluid chamber carrying a fluid. A motor is configured to generate compression and expansion of the fluid in the fluid chamber to generate pressurized fluid. A pressure sensor detects a pressure of the pressurized fluid in the fluid chamber. A garment includes at least one fluid bladder defining a pressurizable chamber adapted to receive the pressurized fluid from the fluid chamber to provide a force of high frequency pressure oscillation to a patient's chest wall.
1 . A high frequency chest wall oscillation therapy system, comprising:
an air pulse generator including:
control circuitry,
a fluid chamber carrying a fluid,
a motor configured to generate compression and expansion of the fluid in the fluid chamber to generate pressurized fluid, and
a pressure sensor coupled to the control circuitry to detect a pressure of the pressurized fluid in the fluid chamber, wherein the control circuitry generates a pressure waveform of the pressurized fluid based on the pressure detected, and
a garment for dressing on a patient's torso, the garment including at least one fluid bladder defining a pressurizable chamber adapted to receive the pressurized fluid from the fluid chamber to provide a force of high frequency pressure oscillation to the patient's chest wall,
wherein the pressure sensor includes:
a tube extending from the pressure sensor to a first port positioned in the fluid chamber to detect the pressure of the pressurized fluid in the fluid chamber, and
a second port positioned outside of the fluid chamber to detect an atmospheric pressure, and
wherein the detected pressure of the pressurized fluid in the fluid chamber is compared to the detected atmospheric pressure to generate the pressure waveform.
2 . The system of claim 1 , wherein:
the fluid chamber is defined between two reciprocating members that are moved toward and away from each other by the motor, and
the pressure is detected by the pressure sensor between the reciprocating members.
3 . The system of claim 2 , wherein the reciprocating members include pistons.
4 . The system of claim 2 , wherein the reciprocating members include diaphragms.
5 . A high frequency chest wall oscillation therapy system, comprising:
an air pulse generator including:
control circuitry,
a fluid chamber carrying a fluid,
a motor configured to generate compression and expansion of the fluid in the fluid chamber to generate pressurized fluid, and
a pressure sensor to detect a pressure of the pressurized fluid in the fluid chamber, wherein the control circuitry generates a pressure waveform of the pressurized fluid based on the pressure detected, and
a garment for dressing on a patient's torso, the garment including at least one fluid bladder defining a pressurizable chamber adapted to receive the pressurized fluid from the fluid chamber to provide a force of high frequency pressure oscillation to the patient's chest wall,
wherein:
the garment produces a unique pressure waveform, and
the pressure waveform generated by the control circuitry from the pressure detected is compared to the unique pressure waveform to identify the garment.
6 . The system of claim 5 , wherein the unique pressure waveform includes at least one of a unique minimum pressure and maximum pressure, a unique peak to peak pressure value, and a unique air pulse generator inflation pressure.
7 . The system of claim 5 , wherein the pressure waveform generated by the control circuitry from the pressure detected is compared to the unique pressure waveform to identify a size of the garment.
8 . A high frequency chest wall oscillation therapy system, comprising:
an air pulse generator including:
control circuitry,
a fluid chamber carrying a fluid,
a motor configured to generate compression and expansion of the fluid in the fluid chamber to generate pressurized fluid, and
a pressure sensor to detect a pressure of the pressurized fluid in the fluid chamber, wherein the control circuitry generates a pressure waveform of the pressurized fluid based on the pressure detected, and
a garment for dressing on a patient's torso, the garment including at least one fluid bladder defining a pressurizable chamber adapted to receive the pressurized fluid from the fluid chamber to provide a force of high frequency pressure oscillation to the patient's chest wall,
wherein the pressure waveform generated by the control circuitry is indicative of a breathing pattern of the patient.
9 . The system of claim 8 , wherein:
the control circuitry stores breathing pattern data indicative of the breathing pattern of the patient in a memory of the air pulse generator, and
a historical assessment of the breathing pattern data is indicative of the patient's lung health.
10 . The system of claim 9 , wherein the breathing pattern data is acquired without an electrical connection between the patient and the control circuitry.
11 . A high frequency chest wall oscillation therapy system, comprising:
an air pulse generator including:
control circuitry,
a fluid chamber carrying a fluid,
a motor configured to generate compression and expansion of the fluid in the fluid chamber to generate pressurized fluid, and
a pressure sensor to detect a pressure of the pressurized fluid in the fluid chamber, wherein the control circuitry generates a pressure waveform of the pressurized fluid based on the pressure detected, and
a garment for dressing on a patient's torso, the garment including at least one fluid bladder defining a pressurizable chamber adapted to receive the pressurized fluid from the fluid chamber to provide a force of high frequency pressure oscillation to the patient's chest wall,
wherein:
the control circuitry derives respiratory data based on the pressure waveform, and
the motor is controlled by the control circuitry to alter a flow of the pressurized fluid from the fluid chamber to the pressurizable chamber based on the respiratory data.
12 . The system of claim 11 , wherein:
the pressure waveform is passed through a low pass filter to derive the respiratory data,
the respiratory data is differentiated to acquire a signal indicative of airflow from the patient, and
the signal indicative of airflow from the patient includes an inhalation segment indicative of inhalation by the patient and an exhalation segment indicative of exhalation of the patient.
13 . The system of claim 11 , wherein the motor is controlled to decrease the flow of the pressurized fluid from the fluid chamber to the pressurizable chamber when the patient inhales.
14 . The system of claim 11 , wherein the motor is controlled to increase the flow of the pressurized fluid from the fluid chamber to the pressurizable chamber when the patient exhales.
15 . The system of claim 11 , wherein the motor is operated at a low state when the patient inhales.
16 . The system of claim 11 , wherein the motor is operated at a high state when the patient exhales.
17 . The system of claim 11 , wherein the force of high frequency pressure oscillation to the patient's chest wall includes a compressive force and an opposite expansive force, wherein the compressive force is configured to be synchronized with an exhalation by the patient.
18 . The system of claim 17 , wherein the expansive force is configured to be synchronized with an inhalation by the patient.