Arterial Blood Gas with Oxygen Saturation and Blood Pressure (via invasive catheter)

Why This Test Is Done

Doctors may order this test if you have trouble breathing, chest pain, severe infections, or other conditions that affect how your body uses oxygen. It’s also used during surgeries, heart procedures, or if you’re in the hospital needing close monitoring of your blood’s oxygen and pressure levels.

What to Expect Before the Test

You’ll likely have an IV started and a small tube (catheter) inserted into an artery, usually in your arm or wrist. The doctor will attach sensors to monitor your heart rate and blood pressure. You may feel a brief pinch when the needle is inserted, but it’s usually over quickly.

What Happens During the Test

Blood samples are taken at intervals to measure oxygen levels (oxygen saturation), carbon dioxide levels, pH balance, and blood pressure. The catheter helps continuously monitor your blood pressure while the test runs.

What the Results Mean

Results help doctors determine if your lungs are working properly, if your blood is getting enough oxygen, and if your blood pressure is stable. Abnormal results may signal conditions like low oxygen, high carbon dioxide, or blood pressure issues that need treatment.