Respiratory monitor
A respiratory monitor is disclosed that includes features for conducting multiple pulmonary function tests in a single device and for detecting the presence of nitric oxide in exhaled breath. Also described is a mouthpiece that allows for separate inhalation and exhalation pathways and for filtering inhaled and exhaled breath for predetermined species prior to exhalation into the respiratory monitor. The monitor further allows for wired, wireless and network connectivity and for cloud-based systems for communicating and correlating pulmonary data as well as relevant environmental data and displaying the data for use by patients and health care professionals.
1. An apparatus, comprising:
a. a housing;
b. a gas inlet section positioned in the housing, comprising:
i. a flow detection component positioned within the gas inlet section;
ii. an adjustable partition positioned downstream from the flow detection component;
iii. a humidity equilibrator positioned downstream from the adjustable partition;
iv. an adjustable flow-restriction component configured to partition the gas inlet section upstream from the humidity equilibrator; and
v. an adjustable inlet for ambient air positioned downstream from the adjustable partition and upstream from the humidity equilibrator; and
c. a measuring assembly located adjacent to and in fluid communication with the gas inlet section; wherein the measuring assembly is configured to determine the total nitric oxide (NO) concentration from an incoming gas sample.
2. A method of determining total nitrogen oxides (NO x ) concentration from a breath sample, comprising:
a. collecting a breath sample from a user using a mouthpiece;
b. flowing the breath sample from the mouthpiece to an inlet portal of an analyzer;
c. flowing the breath sample from the inlet portal of the analyzer to an adjustable flow restrictor positioned within the analyzer;
d. equilibrating the moisture content in the breath sample flowing from the inlet portal and through the analyzer to ambient conditions;
e. admitting ambient air through the analyzer through an adjustable inlet positioned upstream from a humidity equilibrator;
f. forming an equilibrium mixture of nitric oxide (NO) and nitrogen dioxide (NO 2 ) from NO x in the breath sample using a platinum-zeolite reactor element;
g. measuring NO x concentration in the breath sample using a sensor element located downstream from the reactor element;
h. determining total NO concentration in the breath sample based on the measured NO x concentration and equilibrium mixture; and
i. releasing the breath sample through an exhaust portal.