System for automatically weaning a patient from a ventilator, and method thereof

• US 6,463,930 B2
• Filed: 01/22/2001
• Issued: 10/15/2002
• Est. Priority Date: 12/08/1995
• Status: Expired due to Term

• Current Assignee: Bernoulli Enterprise, Inc. (Koninklijke Philips N.V.)
• Original Assignee: Cardiopulmonary Corporation (Koninklijke Philips N.V.)
• Inventors: Reynolds, Robert, Biondi, James W., Lockhorn, Nancy
• Primary Examiner(s): Lewis, Aaron J.
• Assistant Examiner(s): MITCHELL, TEENA KAY
• Application Number:
  US09/767,173
• Publication Number:
  US 20010004893A1
• Time in Patent Office: 631 Days
• Field of Search: 128/204.18, 128/204.21, 128/204.23, 128/204.26, 128/200.24, 128/205.23, 128/207.14, 128/204.22
• US Class Current: 128/204.21
• CPC Class Codes: A61M 16/00 Devices for influencing the respiratory system of patients by gas treatment, e.g. mouth-to-mouth respiration; Tracheal tubes stimulating the respiratory movement by mechanical, pneumatic or electrical means, iron lungs combined with gas breathing means A61H31/00
• CPC Class Codes: A61M 16/0009 with sub-atmospheric pressure, e.g. during expiration
• CPC Class Codes: A61M 16/0012 by Venturi means
• CPC Class Codes: A61M 16/0051 with alarm devices
• CPC Class Codes: A61M 16/0078 Breathing bags
• CPC Class Codes: A61M 16/0081 Bag or bellow in a bottle
• CPC Class Codes: A61M 16/026 specially adapted for predicting, e.g. for determining an information representative of a flow limitation during a ventilation cycle by using a root square technique or a regression analysis
• CPC Class Codes: A61M 16/1015 using a gas flush valve, e.g. oxygen flush valve
• CPC Class Codes: A61M 2016/0021 with a proportional output signal, e.g. from a thermistor
• CPC Class Codes: A61M 2016/0027 pressure meter
• CPC Class Codes: A61M 2016/0039 in the inspiratory circuit
• CPC Class Codes: A61M 2016/0042 in the expiratory circuit
• CPC Class Codes: A61M 2205/505 Touch-screens; Virtual keyboard or keypads; Virtual buttons; Soft keys; Mouse touches

Abstract

A patient ventilator system for automatically weaning a patient from a ventilator.

Claims

1. A method for automatically weaaning a patient from a ventilator, the method comprising the steps of:

(a) providing pressure support to a patient;

(b) detecting a spontaneous patient breath;

(c) measuring the patient'"'"'s spontaneous breathing rate;

(d) measuring the patient'"'"'s minute volume;

(e) comparing the patient'"'"'s spontaneous breathing rate to a predetermined range of breathing rates;

(f) comparing the patient'"'"'s minute volume to a predetermined tidal volume; and

(g) automatically adjusting a patient'"'"'s support level according to the patient'"'"'s spontaneous breathing rate compared to the predetermined range of breathing rates, and the patient'"'"'s minute volume compared to the predetermined minute volume.

2. The method for automatically weaning a patient from the ventilator of claim 1, the method further comprising the step of:

(h) decreasing the patient'"'"'s pressure support level if;

(i) the patient'"'"'s spontaneous breathing rate falls within the predetermined range of breathing rates, and,

(ii) the patient'"'"'s minute volume exceeds the predetermined minute volume.

3. The method for automatically weaning a patient from the ventilator of claim 1, the method further comprising the step of:

(h) increasing the patient'"'"'s support level if;

(i) the patient'"'"'s spontaneous breathing rate falls outside the predetermined range of breathing rate; and

(ii) the patient'"'"'s minute volume is exceeded by the predetermined minute volume.

4. The method of claim 1 further comprising adjusting the amount of pressure support between zero and PEEP.

5. The method of claim 1 wherein the patient'"'"'s pressure support level is decreased by a rate between 0.01% and 0.1%.

6. The method of claim 1 further comprising setting a low pressure alarm limit.

7. The method of claim 1 wherein measuring the patient'"'"'s spontaneous breath rate further comprises calculating an average breath rate and a current breath rate from patient'"'"'s spontaneous breath rate to obtain the patient'"'"'s breath rate.

8. A ventilator system for automatically weaning a patient from a ventilator, comprising:

a source of pressure in communication with the patient to provide pressure support to the patient;

a spontaneous breathing rate monitor;

an input device for receiving input values for a predetermined breath rate range and a predetermined minute tidal volume;

a minute volume flow meter; and

a data processing unit in electrical communication with said pressure source, said breathing rate monitor, said flow meter, and said input device, wherein, said data processing unit calculates an average breath rate and a current breath rate from a signal from said breathing rate monitor to obtain the patient'"'"'s breath rate, compares the patient'"'"'s breath rate to the predetermined breath rate range, compares the patient'"'"'s minute tidal volume to the predetermined minute tidal volume, and automatically adjusts the pressure source to change pressure support to the patient in response thereto.

9. The ventilator system of claim 8 wherein said source of pressure comprises a pneumatic system comprising a flexible airway, a source of pressurized gas, a rigid chamber, a flexible chamber and a Venturi valve.

10. The ventilator system of claim 9 further comprising a high speed pneumatically driven, electronically controlled proportional valve and dual Venturi systems.

11. The ventilator system of claim 8 wherein said input device is a touch screen in electrical communication with a display controller processor.

12. The ventilator system of claim 8 wherein said data processing unit is a real time data processor in electrical communication with a ventilatory unit processor and an airway processor.

13. A method for automatically weaning a patient from a ventilator, the method comprising the steps of:

providing pressure support to the patient;

determining the patient'"'"'s spontaneous breathing rate;

inputting values for a predetermined patient breath rate range and a predetermined minute volume;

measuring the patient minute volume;

comparing the patient'"'"'s breath rate to the predetermined breath rate range;

comparing the patient'"'"'s minute volume to the predetermined minute volume; and

automatically adjusting pressure support to the patient in response thereto.

14. The method of claim 13 further comprising calculating an average breath rate and a current breath rate to obtain the patient'"'"'s reath rate.