Cardiac Output Testing

What is the purpose of cardiac output testing?

The purpose of this test is to assess how much blood the hear can pump (cardiac output) by measuring pulmonary blood flow.

How is the test performed?

During this test, a clamp will be placed on the nose so that the patient will breathe through his/her mouth. The patient will then be instructed to breathe through a device. This device, in addition to containing oxygen, also contains two inert gases. One of these gases is soluble in blood and disappears over time at a rate proportional to pulmonary blood flow as the patient breathes. The other gas does not enter the bloodstream and allows lung volume to be measured.