Steady-State Posture Gating for Accurate Physiologic Monitoring
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Medical devices face challenges in accurately monitoring physiological signals due to variations caused by patient posture, which can lead to false positives or masked changes in cardiac disease diagnosis.
Innovation Solution
Incorporating a posture sensing circuit and a processor circuit that determine steady-state posture, allowing for the derivation of physiologic measurements only during stable postures, thereby reducing physiologic noise and improving diagnostic accuracy.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If physiologic measurements are continuously monitored without posture consideration, then monitoring coverage is maximized, but measurement precision deteriorates due to posture-induced variability
Solution Approach 1:
The system performs preliminary posture detection and classification before acquiring physiologic measurements. By determining whether the patient is in a steady-state posture (supine, sitting, or standing) prior to measurement, the system filters out measurements taken during transient posture changes, thereby improving measurement precision without significantly reducing monitoring coverage.
Solution Approach 2:
The system continuously monitors posture and uses this feedback to gate physiologic measurements. When posture transitions are detected, the system pauses measurement acquisition until steady-state posture is confirmed, creating a feedback loop that ensures measurement precision while maintaining overall monitoring productivity through selective measurement timing.
2Reliability
If all physiologic data is collected regardless of posture stability, then data volume increases, but reliability decreases due to noise from transient postures
Solution Approach 1:
The system extracts and removes measurements taken during transient or unstable postures from the overall data set. By identifying and excluding these unreliable measurements, the system increases the proportion of high-quality data, thereby improving diagnostic accuracy without requiring a complete rejection of all collected data.
Solution Approach 2:
The system changes the selection criterion for physiologic data based on posture parameters. Instead of collecting all measurements uniformly, the system adjusts data acquisition based on detected posture stability, accepting measurements only when posture parameters indicate steady-state conditions, thus improving reliability while managing data volume.
3Measurement precision
If posture monitoring is added to existing medical devices, then measurement precision improves, but device complexity increases
Solution Approach 1:
The system uses a multi-functional approach where the posture sensing circuit serves dual purposes: it monitors posture for measurement gating and also provides diagnostic information about patient condition. This multi-functionality reduces the need for separate dedicated systems, thereby improving measurement precision while minimizing the increase in device complexity.
Solution Approach 2:
The system merges the posture monitoring function with the existing physiologic monitoring infrastructure. By combining posture detection circuits with the signal processing and display systems already present in the medical device, the system achieves improved measurement precision without proportionally increasing overall device complexity.
Data Source
AI summary
An implantable or other ambulatory medical apparatus comprises a posture sensing circuit, a physiologic sensing circuit that senses a time varying physiologic signal, and a processor circuit. The processor circuit includes a posture calculation circuit and a measurement circuit. The posture calculation circuit determines a posture of the subject using posture data obtained using the posture signal and determines when the posture of the subject is steady state. The measurement circuit derives a physiologic measurement using physiologic data extracted from the physiologic signal during at least one time period when posture is determined to be steady state and provides the physiologic measurement to at least one of a user and a process in association with the determined steady state posture.