Arterial Blood Gases. Test Overview. An arterial blood gas (ABG) test measures the acidity (pH) and the levels of oxygen and carbon dioxide in the blood from an artery. This test is used to check how well your lungs are able to move oxygen into the blood and remove carbon dioxide from the blood.
How Often the Test Is Done During Your Pregnancy. Your doctor may use the Doppler often to listen to your baby's heartbeat during routine checkups, starting at about 8 to 10 weeks. Handheld Dopplers will not work quite this early.
Arrhythmia monitoring refers to tests physicians use to identify the type and the cause of irregular heart rhythms. Many arrhythmias occur infrequently, so to record the heart's electrical activity under real-world conditions, physicians use continuous monitor recording, also called ambulatory electrocardiography.