Pulse Oximetry Sensor Motion Correction via Position Indicators
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Pulse oximetry measurements are affected by motion and changes in tissue position, leading to interference and reduced accuracy due to variations in the optical path between the sensor's emitter and detector, causing false indications in physiological parameters.
Innovation Solution
A system that uses a position indicator to measure the spatial and temporal position of the emitter and detector, processing this data synchronously with pulse oximetry data to calculate correction factors and reduce noise, employing algorithms and optical path length functions to correct for interference.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Adaptability or versatility
If motion of the sensor relative to the tissue occurs, then the spatial relationship between sensor and tissue changes, but this causes variations in light intensities detected and reduces measurement accuracy
Solution Approach 1:
The system performs preliminary action by measuring the position of the emitter and detector using position indicators before the pulse oximetry measurement is taken. This position data is then used to calculate correction factors that compensate for motion-induced optical path changes during the actual measurement, thereby maintaining measurement accuracy even when sensor position changes occur.
2Ease of operation
If the optical path between emitter and detector changes due to tissue position changes, then different tissue structures are illuminated, but this causes interference and false indications in physiological parameters
Solution Approach 1:
The system implements feedback by continuously monitoring the position of the emitter and detector using position indicators, calculating correction factors based on position changes, and applying these corrections to the pulse oximetry measurements. This closed-loop feedback mechanism compensates for motion-induced interference and maintains reliable physiological parameter measurements even when patient movement occurs.
3Measurement precision
If correction factors are calculated using position data, then interference is reduced, but this requires additional position indicator components and processing
Solution Approach 1:
The system applies universality by using the position indicators and position processing algorithms for multiple purposes: they not only correct pulse oximetry measurements for motion artifacts but can also potentially track patient movement patterns, assess compliance with sensor positioning, and provide data for other motion-sensitive physiological measurements, thereby justifying the added complexity through multiple functional benefits.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach significantly enhances the accuracy and reliability of pulse oximetry measurements by mitigating interference caused by motion and tissue position changes, providing more precise physiological parameter data.
Implementation Method 1
A position indicator (14) measures a spatial and temporal position of the emitter (56) and the detector (57)
Implementation Method 2
Pulse oximeters typically utilize a non-invasive sensor that transmits light through a patient's tissue and that photoelectrically senses the absorption and/or scattering of the transmitted light in such tissue
Implementation Method 3
The light passed through the tissue is typically selected to be of one or more wavelengths that may be absorbed or scattered by the blood in an amount correlative to the amount of the blood constituent present in the blood
Implementation Method 4
A processing unit (20) processes the pulse oximetry data (18) and position data (16) synchronously. The processed position data is used to calculate correction factors/parameters that correct the pulse oximetry data for interference
Data Source
AI summary
A pulse oximetry sensor adapted to emit light from an emitter proximate to a patient's tissue and detect a portion of the emitted light on a detector proximate to the tissue. The pulse oximetry system is adapted to acquire position data for the emitter and for the detector with one or more position indicators. The pulse oximetry system is adapted to process the position data to obtain a change in position of the emitter and the detector; and to process pulse oximetry measurements using the change in position to obtain a motion-corrected pulse oximetry data.