Tetrapolar High-Frequency Impedance Pneumograph
Generates 50 kHz constant-current excitation (200 μA RMS) and detects differential voltage.
Biomedical Engineering / Impedance Pneumography
FREE TO EXPLORELABORATORY 16 · BIOMEDICAL ENGINEERING
Transthoracic Electrical Impedance Pneumography & Tidal Volume Scaling
Measure high-frequency (50 kHz) four-electrode transthoracic electrical impedance changes (ΔZ) during breathing cycles and calibrate against spirometric tidal volume. Explore interactive physiological instrumentation simulation, biomechanics, and biomedical engineering telemetry.
BIOINSTRUMENTATION · BIOSIGNALS · BIOMECHANICS · IMAGING
Your virtual biomedical engineering laboratory.
TRANSTHORACIC IMPEDANCE AMPLITUDE ΔZ—
PHYSIOLOGICAL & TEST CELL TELEMETRY
Ready to sample with Volume V_t = 1.5 L.
Adjust Volume V_t, then execute biomedical trial.
Biomedical engineering telemetry and physiological states are evaluated rigorously using 64-bit IEEE 754 precision. Residuals reflect ordinary least-squares regression across successive observations. Continuous data structures support high-fidelity biological and physiological modeling.
Biomedical assumptions and boundary condition limits
The linear sensitivity model applies across normal physiological tidal volumes (0.5 to 3.0 L). Evaluated using a four-electrode tetrapolar chest band montage at mid-axillary level (6th intercostal space) with 50 kHz, 200 μA RMS carrier excitation. Synchronously calibrated against a turbine spirometer across voluntary tidal volumes from 0.5 L to 3.0 L.
Biomedical apparatus & physiological sensors.
Calibrated Turbine Digital Spirometer
Provides gold-standard primary reference measurement of inspired and expired tidal volume in Liters.
Four Sintered Ag/AgCl Disposable Pre-Gelled Electrodes
Affixed in bilateral mid-axillary line across the 6th intercostal space (tetrapolar arrangement).
Precision Synchronous AM Demodulator & Bandpass Filter
Demodulates 50 kHz carrier and filters respiratory band (0.05 to 2.0 Hz).
Cardiogenic Artifact Rejection Filter
Suppresses small (0.1 to 0.2 Ω) cardiogenic impedance oscillations synchronous with heartbeats.
Multi-Channel Bio-Telemetry Logging Workstation
Simultaneously records spirometry flow, integrated volume V_t, and thoracic impedance ΔZ.
FOLLOW THE METHOD
A reason behind every step.
Measure high-frequency (50 kHz) four-electrode transthoracic electrical impedance changes (ΔZ) during breathing cycles and calibrate against spirometric tidal volume. Standardized parameter settings: 0.5, 1.0, 1.5, 2.0, 2.5, 3.0 L.
01
Tetrapolar Electrode Montage Application
Clean skin with alcohol wipes and affix four electrodes along the mid-axillary line: outer pair for 50 kHz current injection, inner pair for voltage pickup.
02
Baseline Impedance Balance and Carrier Setup
Energize 50 kHz 200 μA oscillator; record baseline thoracic resting end-expiratory impedance (Z_0, typically 25 to 50 Ω).
03
Simultaneous Spirometer Coupling
Seat subject comfortably and fit nose clip; connect subject to calibrated turbine spirometer to log air volume simultaneously.
04
Standardized Shallow Inhalation (0.5 L)
Instruct subject to inhale to achieve a spirometric tidal volume V_t of exactly 0.50 L; log stabilized peak impedance excursion ΔZ in Ohms.
05
Tidal Volume Step Progression
Guide subject through voluntary breathing increments of 1.0, 1.5, 2.0, 2.5, and 3.0 L, recording paired (V_t, ΔZ) values across 5 breaths per step.
06
Pneumographic Sensitivity Regression
Plot respiratory impedance amplitude ΔZ against tidal volume V_t, fitting linear regression through the origin to determine sensitivity k_v.
YOUR NOTEBOOK · 0 OBSERVATIONS
Turn measurements into biomedical engineering insight.
Points are your recorded observations. The solid regression line validates Impedance Pneumography mathematical scaling.
LINEAR REGRESSION FIT · y = mx + b
ΔZ = k_v · V_t = 1.3500 · V_t
| # | Spirometric Tidal Volume V_t (L) | Transthoracic Impedance Amplitude ΔZ (Ω) | Tidal volume V_t (L) | Transthoracic impedance change ΔZ (Ω) | Remove |
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