Which test measures the levels of both oxygen and carbon dioxide in the blood?
|
Show Recommended textbook solutions
The Human Body in Health and Disease7th EditionGary A. Thibodeau, Kevin T. Patton 1,505 solutions
 Pharmacology and the Nursing Process7th EditionJulie S Snyder, Linda Lilley, Shelly Collins 388 solutions
Exercise Physiology: Theory and Application to Fitness and Performance11th EditionEdward Howley, John Quindry, Scott Powers 593 solutions
Administering Medications9th EditionDonna F Gauwitz 1,201 solutions Topic Resources Both arterial blood gas testing and pulse oximetry measure the amount of oxygen in the blood, which helps determine how well the lungs are functioning. Arterial blood gas tests are invasive, requiring a blood sample, and provide information at a specific moment in time. Pulse oximetry is not invasive. It uses a
sensor attached to the person's finger. It can also provide continuous measurements of the amount of oxygen in the blood. Arterial blood gas tests measure the levels of oxygen and carbon dioxide in the arterial blood and determine the acidity (pH) of the blood. Taking a blood sample from an artery using a needle may cause a few minutes of discomfort. Usually the sample is taken from an artery in the wrist (radial artery). Oxygen, carbon dioxide, and acidity levels are
important indicators of lung function because they reflect how well the lungs are getting oxygen into the blood and getting carbon dioxide out of it. There are newer ways of measuring carbon dioxide in exhaled breath that do not require blood samples, but these methods are less accurate and not always available. The amount of oxygen in the blood can be monitored without taking a blood sample by using a sensor placed on a finger or an earlobe—a procedure called
pulse oximetry. However, when a doctor also needs a carbon dioxide or blood acidity measurement (for example, in certain people who are seriously ill), an arterial or venous blood gas measurement is usually needed. An arterial blood gas measurement can also give a more exact measurement than pulse oximetry. Doctors may do pulse oximetry as or after the person walks around or climbs a flight of stairs to see if exertion causes oxygen levels in the blood to decrease. CLICK HERE FOR THE PROFESSIONAL VERSION Copyright © 2022 Merck & Co., Inc., Rahway, NJ, USA and its affiliates. All rights reserved. Test OverviewAn arterial blood gases (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 find out how well your lungs are able to move oxygen into the blood and remove carbon dioxide from the blood. As blood passes through your lungs, oxygen moves into the blood while carbon dioxide moves out of the blood into the lungs. An ABG test uses blood drawn from an artery, where the oxygen and carbon dioxide levels can be measured before they enter body tissues. An ABG measures: Partial pressure of oxygen (PaO2).This measures the pressure of oxygen dissolved in the blood and how well oxygen is able to move from the airspace of the lungs into the blood. Partial pressure of carbon dioxide (PaCO2).This measures the pressure of carbon dioxide dissolved in the blood and how well carbon dioxide is able to move out of the body. pH.The pH measures hydrogen ions (H+) in blood. The pH of blood is usually between 7.35 and 7.45. A pH of less than 7.0 is called acid and a pH greater than 7.0 is called basic (alkaline). So blood is slightly basic. Bicarbonate (HCO3).Bicarbonate is a chemical (buffer) that keeps the pH of blood from becoming too acidic or too basic. Oxygen content (O2CT) and oxygen saturation (O2Sat) values.O2 content measures the amount of oxygen in the blood. Oxygen saturation measures how much of the hemoglobin in the red blood cells is carrying oxygen (O2). Blood for an ABG test is taken from an artery. Most other blood tests are done on a sample of blood taken from a vein, after the blood has already passed through the body's tissues where the oxygen is used up and carbon dioxide is produced. Why It Is DoneAn arterial blood gases (ABG) test is done to:
How To Prepare
How It Is DoneIf you are on oxygen therapy, the oxygen may be turned off for 20 minutes before the blood test. This is called a "room air" test. But if you can't breathe without the oxygen, the oxygen won't be turned off. A sample of blood from an artery is usually taken from the inside of the wrist (radial artery). But it can also be taken from an artery in the groin (femoral artery) or on the inside of the arm above the elbow crease (brachial artery). If blood is taken from the wrist, you will be seated with your arm extended and your wrist resting on a small pillow. The health professional taking the blood may rotate your hand back and forth and feel for a pulse in your wrist. A procedure called the Allen test may be done to make sure that the blood flow to your hand is normal. An ABG test will not be done on an arm used for dialysis or if there is an infection or inflammation in the area of the puncture site. How It FeelsCollecting blood from an artery is more painful than collecting it from a vein. That's because the arteries are deeper and are surrounded by nerves.
RisksThere is little chance of a problem from having a blood sample taken from an artery.
ResultsNormalEach lab has a different range for what's normal. Your lab report should show the range that your lab uses for each test. The normal range is just a guide. Your doctor will also look at your results based on your age, health, and other factors. A value that isn't in the normal range may still be normal for you. Results are usually available right away. The concentration of oxygen being breathed, called the fraction of inhaled oxygen (FiO2), is also usually reported. This is only useful if you are receiving oxygen therapy from a tank or are on a ventilator. Many conditions can change blood gas levels. Your doctor will talk with you about any abnormal results that may be related to your symptoms and past health. CreditsCurrent as of: March 9, 2022 Author: Healthwise Staff Is there a blood test for carbon dioxide?A CO2 blood test is often part of a group of tests called an electrolyte panel. An electrolyte panel may be part of a regular check-up. The test may also help diagnose or monitor conditions related to an electrolyte imbalance. These include high blood pressure and diseases of the kidneys, lungs, or liver.
What does ABG measure?Blood gases are a measurement of how much oxygen and carbon dioxide are in your blood. They also determine the acidity (pH) of your blood. The blood gases test is performed by collecting a sample of blood through a needle from an artery.
What test measures oxygen carbon dioxide and pH levels in the blood quizlet?Arterial Blood Gas (ABG) is defined as: "The measurement of the acidity and the levels of oxygen and carbon dioxide in the blood from an artery." ABG are tests which are used to check how well a patient's respiratory efforts are able to move oxygen into the blood and remove carbon dioxide from the blood..
Why is ABG test done?An arterial blood gas (ABG) test measures oxygen and carbon dioxide levels in your blood. It also measures your body's acid-base (pH) level, which is usually in balance when you're healthy. You may get this test if you're in the hospital or if you have a serious injury or illness.
|
