Impedance cardiography

Impedance cardiography (ICG) is a noninvasive healthcare technology used to measure the total electrical conductivity of the thorax and the changes in this conductivity during the cardiac cycle. The technique is used for non-invasive cardiac output monitoring and detecting cardiovascular conditions.

Overview

Impedance cardiography is based on the principle that the electrical conductivity of the thorax changes with the volume of blood in the aorta. The technique involves passing a small electrical current through the thorax and measuring the resulting voltage drop, which provides a measure of thoracic impedance. Changes in this impedance can be used to calculate cardiac output and other parameters of cardiovascular function.

Clinical Applications

Impedance cardiography has a wide range of clinical applications. It is used in the diagnosis and management of various cardiovascular conditions, including heart failure, hypertension, and cardiomyopathy. It is also used in the monitoring of patients undergoing cardiac surgery or receiving intensive care.

Advantages and Limitations

The main advantage of impedance cardiography is that it is non-invasive and can be performed at the bedside. It provides continuous, real-time monitoring of cardiac output and other cardiovascular parameters. However, the technique has some limitations. It requires careful electrode placement and calibration, and its accuracy can be affected by factors such as patient movement and changes in thoracic composition.

See Also

• Cardiac output
• Cardiovascular system
• Heart failure
• Hypertension
• Cardiomyopathy

References

<references />

Impedance cardiography

• 
  Relationship between Aortic Blood Pressure and Aortic Blood Flow
• 
  Frank-Starling Law and Inotropy
• 
  Timing considerations of hemodynamic modulation