The arterial blood gases test are used like other blood gas measurements are used: to evaluate the functioning of a person’s lungs and their acid-base balance.
These blood tests are ordered usually when someone is having symptoms that are worsening when there is a respiratory issue present. The feeling of being short of breath or having breathing issues, such as with asthma or COPD, will often trigger a medical provider to order this test. It may also be used to monitor the treatment plan instituted for certain lung diseases or oxygen therapies.
When these blood tests are used to detect acid-base imbalances, the results can help to determine if someone is suffering from a severe infection, diabetes, or an acute issues like a drug overdose.
Other Instances When Arterial Blood Gases Tests Are Ordered
This blood test may be ordered when a medical provider suspects that someone has been experiencing a carbon dioxide or pH imbalance. Nausea and vomiting may be present instead of a difficulty breathing or feeling short of breath. Any time respiratory distress is being experienced, especially when there is a metabolic disease or kidney disease present, will often be a cause for the arterial blood gases test being ordered.
Certain injuries will also cause a medical provider to order this test, even if bothersome signs and symptoms are not being experienced. This is particularly true for people who have suffered an injury to their neck or head, which could affect their breathing.
Surgeons often order this blood test if prolonged anesthesia is expected to correct a health issue, such as a brain surgery or a cardiac bypass surgery. This will help to monitor health conditions, before, during, and after the procedure takes place.
Some newborns may also benefit from having this test done on blood from the umbilical cord to uncover respiratory problems. This is usually done only if a newborn is struggling to breathe normally after birth.
What Do the Arterial Blood Gases Test Results Mean?
It is important to note that with this particular test, the normal results can vary widely between testing laboratories. The geographic location of where the test takes place will also affect results. People who live at high levels above sea level will have lower levels of blood oxygen levels than someone who lives at a low elevation. A patient in Denver, for example, will have different baseline “normal” levels than someone living in Seattle.
It is also important to note that the results of an arterial blood gas test are not considered to be a diagnostic finding. This blood test is used in combination with other results, tests, and exams to determine the exact status of patient health.
If abnormal results are being reported, then this generally means the individual being tested is not getting enough oxygen. It can also mean that they are not getting rid of enough carbon dioxide. In some patients, it may indicate an issue with kidney function.
If acid-base testing is being performed, then the pH result can indicate some common health issues when combined with bicarbonate and PaCO2 testing. A pH result less than 7.35 may indicate kidney failure, shock, diabetic ketoacidosis, intoxication, a drug overdose, asthma, or COPD.
If the pH result is higher than 7.45, then this may indicate heart failure, low blood potassium, cirrhosis, hyperventilation, chronic pain, chronic anxiety, pneumonia, or a trauma that has occurred to the brain.
Here’s What You Need To Know
The blood draw for the arterial blood gases tests is usually more painful than other blood draws. A compress may be required to stop bleeding at the collection site and moderate discomfort may be felt for 24-48 hours after the sample collection.
Sometimes this test will be performed on mixed blood taken from a vein, especially in hospital settings. This may produce different results than mentioned in this guide.
Because this test must be administered immediately after collection, the sample will not usually be taken at a doctor’s office. Patients will be referred to a hospital, surgical center, or other large laboratory setting for accurate results.
For those suffering from chronic asthma or pneumonia symptoms, physical exams are usually what are ordered to determine current health status. This blood test will be ordered for most only if there are severe or acute breathing problems which have an immediate impact on the quality of life being experienced.
If you have any questions about your arterial blood gases test or that of a loved one, then speak with the attending doctor who ordered the test in the first place. They will be able to compare results to a personal medical history so that the best chance of an accurate diagnosis, with other tests, can be achieved.