68 results about "Plethysmograph" patented technology

A method and an apparatus for measuring a physiological parameter, functioning based on obtaining a first signal derived from electromagnetic energy transmitted through a tissue portion at a first wavelength, the first signal including a signal portion corresponding with motion-related events and a signal portion corresponding with arterial pulsation events, where at the first wavelength water is a dominant absorber of electromagnetic energy in the tissue portion; obtaining a second signal derived from electromagnetic energy transmitted through a tissue portion at a second wavelength, the second signal including a signal portion corresponding with motion-related events and a signal portion corresponding with arterial pulsation events, where at the second wavelength hemoglobin is a dominant absorber of electromagnetic energy in the tissue portion; and combining the first signal and the second signal to generate a combined plethysmograph signal, such that the combined signal has a signal portion corresponding with motion-related events that is smaller than that present in the first signal or the second signal.

A method and system for measuring a physiological parameter, comprising collecting a first absorbance at a first wavelength, chosen to be primarily absorbed by water; collecting a second absorbance at a second wavelength, chosen to be primarily absorbed by hemoglobin; and combining the first signal and the second signal to generate a combined plethysmograph signal which is proportionate lower in noise caused by motion-related interference.

Disclosed herein are methods and devices for delivering gas to a subject and obtaining plethysmograph readings from a subject. Specifically disclosed herein are masks and helmets which comprise one or more pulse oximeter probes associated therewith. The masks and helmets may be used in particular contexts, including, but not limited to, emergency responder personnel, pilots or subjects of medical attention.

A method and apparatus are described for utilizing a source of vascular pulse waveform data from a patient for the purpose of measuring pulsus paradoxus. The arterial pulse waveform data source described is a pulse oximeter plethysmograph but can be any similar waveform data source, including an intra-arterial transducer, external blood pressure transducer, or plethysmograph. Through incorporation of measurements of values, such as an area under a pulse waveform curve, that are time-domain functions of a change in amplitude of the pulse waveform over a duration of the waveform, embodiments of the present invention represent a significant improvement upon previously described methods of measuring pulsus paradoxus.

A method and system for operating a non-invasive blood pressure monitor that utilizes an SpO2 plethysmographic signal to reduce the time required to obtain an estimation of a patient's blood pressure. During operation of the NIBP monitor, the NIBP monitor utilizes the SpO2 plethysmographic signal to determine a timing period and a deflation period for each pulse associated with the patient's heartbeat. Upon receiving an oscillation pulse, the NIBP monitor determines the oscillation amplitude during the timing period and deflates the blood pressure cuff during the deflation period immediately following the timing period. Preferably, the deflation period occurs during the same oscillation pulse used to calculate the oscillation pulse amplitude to decrease the amount of time required to obtain a blood pressure estimate from the patient.

A method and system for operating a non-invasive blood pressure monitor that utilizes an SpO2 plethysmograph signal to determine the initial inflation pressure for the blood pressure cuff of the NIBP monitor. A pulse sensor is placed on the patient's limb distal to the blood pressure cuff such that as the blood pressure cuff is inflated, the pulse signals from the pulse sensor will be reduced. When the blood pressure cuff reaches systolic pressure, the pulse signals from the pulse sensor will be initially attenuated and eventually eliminated, thus providing an indication that the cuff pressure has reached systolic pressure for the patient. The central processor of the NIBP monitor compares the pulse signals during cuff inflation to an average pulse signal and terminates the inflation of the blood pressure cuff upon sufficient attenuation. The use of the SpO2 plethysmograph signal to determine the initial inflation pressure reduces both the over-inflation of the blood pressure cuff and the under-inflation of the blood pressure cuff which increases the rate at which the blood pressure measurement can be made while increasing patient comfort.

Disclosed herein are methods and devices of obtaining plethysmograph readings and utilizing plethysomography to identify when pilots are about to experience GLOC. Furthermore, in other embodiments, the invention pertains to methods and devices designed to warn a pilot that he / she is about to enter GLOC and / or automatically averting catastrophic damage or injuries by directing a plane being piloted to take predetermined corrective actions. Specifically disclosed is a system embodiment for assisting in the prevention of gravity induced loss of consciousness. The system comprises at least one pulse oximeter probe 10 configured for securing to a central source site of a pilot and to generate signals indicative of blood flow at said central source site, an analyzer unit 58 communicatingly connected to said at least one pulse oximeter probe 10, said analyzer unit comprising at least one processing module 56 configured to determine whether said blood flow is approaching a predefined level, and an aircraft computer 51 communicatingly connected to said analyzer unit 58, said aircraft computer 51 comprising at least one processing module 59 configured to effect a predetermined reaction responsive to said blood flow falling below a predetermined level.