BIOPAC® Systems, Inc. Logo

Stroke volume

Models designed to infer stroke volumes based on changes in thoracic impedance rely on many simplifying assumptions. These assumptions are not universally valid. Consequently the relationship between measured impedances and the absolute amount of blood moving into and out of the heart is not adequately characterized. For more background, see references cited in “What types of electrode should I use?”. AcqKnowledge offers different models via “Analysis > Impedance Cardiography > Preferences…”. The “Stroke Volume methods” are not proprietary; they have been taken from the ICG literature. If you would like to utilize a different model, please contact support to suggest that model be incorporated as an alternative, or, if needed, ask for help implementing it in current software.

There is also some debate as to the best placement of electrodes for measuring impedance through the thorax. See “Where do I place electrodes/sensors/transducers?” for additional discussion.

Page last modified 19Jan2015

Spotlight On
Cardiac Output amplifier

NICO Smart Amplifier

The NICO Smart Amplifier is specifically designed to measure thoracic impedance for performing noninvasive cardiac output measurements. The amplifier terminates in two connectors for impedance (Z) and its derivative (dZ), and has a 3 m cable that connects directly to an AMI100D Amplifier Input Module. Use with EL500 series disposable electrodes and LEAD131 for a four-spot […]

View All
Latest News

New Citations | BIOPAC in NIBP Studies

NIRS and CNAP—Pairing great tools for great data Cerebral hemoglobin concentration (blood mass in the brain) is frequently measured in the prefrontal cortex, and systemic arterial blood pressure is known to be a variable factor based on the hemoglobin concentration. A leg pressure cuff was used to constrict and release blood flow to create a […]

Electrocardiography Guide Now Available

BIOPAC’s just released Introductory ECG Guide addresses fundamental to advanced concerns to optimize electrocardiography data recording and analysis. Topics include: ECG Complex; Electrical and Mechanical Sequence of a Heartbeat; Systole and Diastole; Configurations for Lead I, Lead II, Lead III, 6-lead ECG, 12-lead ECG, precordial leads; Ventricular Late Potentials (VLPs); ECG Measurement Tools; Automated Analysis Routines […]

Read All
Request a Demonstration
Request a Demonstration