Metering system for stimulating bronchial spasm

• US 4,106,503 A
• Filed: 03/11/1977
• Issued: 08/15/1978
• Est. Priority Date: 03/11/1977
• Status: Expired due to Term

• Current Assignee: Laboratory For Applied Immunology Incorporated
• Original Assignee: Richard R. Rosenthal
• Inventors: French, Joseph, Rosenthal, Richard R.
• Primary Examiner(s): Recla, Henry J.
• Application Number:
  US05/776,662
• Time in Patent Office: 522 Days
• Field of Search: 128/194, 128/193, 128/188, 128/2.08, 128/173 R, 128/184, 128/213 R, 128/DIG. 2, 128/145.6, 128/145.8, 128/142.2, 128/201
• US Class Current: 128/200.18
• CPC Class Codes: A61M 11/06 of the injector type
• CPC Class Codes: A61M 15/00 Inhalators drug delivery in endotracheal tubes A61M16/04
• CPC Class Codes: A61M 15/0066 with means for varying the dose size
• CPC Class Codes: A61M 15/0083 Timers
• CPC Class Codes: A61M 2016/0021 with a proportional output signal, e.g. from a thermistor

Abstract

A system for administering a metered dose of nebulized antigen tests a patient'"'"'s pulmonary response. The system includes a thermistor detector for sensing initiation of patient inhalation. A variable electronic timer meters the amount of nebulized antigen introduced to the patient. Safety switching means is provided for insuring against erroneous administration of more than a single dose at a time. Separate measuring equipment is used to measure pulmonary airflow resistance which will increase in response to bronchial spasm.

Claims

1. A system for metering an aerosol provocative substance for patient inhalation comprising:

nebulizing means for normally containing the provocative substance in a liquid medium, the nebulizing means having an inlet and an outlet, the outlet delivering nebulized provocative substance to a patient;

means mounted to the nebulizing means for detecting the initiation of inhalation by the patient and generating a detection signal in response thereto;

timing means having its input connected in circuit with the detecting means and responsive thereto for generating a timing signal of preselected duration;

a source of compressed gas;

valving means responsive to said timing signal and driven open during the timing signal and connected between the gas source and said inlet of the nebulizer for nebulizing a metered dose of the nebulized provocative substance, depending upon the timing signal duration;

means connected in circuit between the detecting means and the timing means for triggering the timing means;

gating means connected in circuit between the output of the triggering means and the input of the timing means for permitting the passage of a triggering signal to the timing means;

means responsive to the end of the timing signal for blocking the gating means from passage of an erroneous trigger signal; and

means for selectively resetting the blocking means thereby enabling a subsequent passage of a triggering signal.

2. A system for metering an aerosol provocative substance for patient inhalation comprising:

nebulizing means for normally containing the provocative substance in a liquid medium, the nebulizing means having an inlet and an outlet, the outlet delivering nebulized provocative substance to a patient;

means mounted to the nebulizing means for detecting the initiation of inhalation by the patient and generating a detection signal in response thereto;

timing means having its input connected in circuit with the detecting means and responsive thereto for generating a timing signal of preselected duration;

a source of compressed gas;

valving means responsive to said timing signal and driven open during the timing signal and connected between the gas source and said inlet of the nebulizer for nebulizing a metered dose of the nebulized provocative substance, depending upon the timing signal duration;

means connected in circuit between the detecting means and the timing means for triggering the timing means;

the detecting means being a thermistor having a surface which changes its temperature as air flows across it during inhalation initiation;

a relay having an input thereof connected to the timing means output, the relay being connected at its output to the valving means for the control thereof;

gating means connected in circuit between the output of the triggering means and the input of the timing means for permitting the passage of a triggering signal to the timing means;

means responsive to the end of the timing signal for blocking the gating means from passage of an erroneous trigger signal; and

means for selectively resetting the blocking means thereby enabling a subsequent passage of a triggering signal.