An arterial blood gas, or ABG, test is a diagnostic tool for uncovering a variety of potential medical conditions. A blood sample from the patient’s body is analyzed for two important health indicators:

• Oxygen and carbon dioxide levels, and
• Degree of acidity (the pH scale).

Blood gas levels or pH readings outside of normal, healthy ranges can be medical red flags, spurring further testing and investigation. Respiratory ailments, such as asthma and chronic obstructive pulmonary disorder (COPD), are among those identified by ABG tests.

Respiratory care is a major focus at Baptist Health. Our physicians, therapists, and other providers stay up-to-date with the latest advances in treating pulmonary conditions and diseases. You’ll receive the best that medicine has to offer, always with a human touch.

Why Would I Receive an Arterial Blood Gas Test?

ABG tests are often used to diagnose the medical condition of patients suffering from respiratory symptoms or discomfort. Blood gas imbalances can point to the presence of:

• Asthma
• Bronchitis
• COPD
• Cystic fibrosis
• Emphysema.

These tests have other uses as well. They can measure the effectiveness of medications in treating respiratory conditions, help prepare patients for surgery, and document the need for supplemental oxygen. Blood acidity data plays a role in the diagnosis of non-respiratory illnesses and conditions, including infections, kidney failure, diabetes, and drug overdoses.

How Will Arterial Blood Gas Testing Help My Condition?

An ABG test can provide your physician with the information he or she needs to formulate a diagnosis for the symptoms you’re experiencing. You’ll have more and better treatment options when the underlying cause is known. ABG tests can also document a medical condition’s progress, enabling your medical team to adjust medications and therapies and step up your care.

What Should I Expect from Arterial Blood Gas Testing?

You’ll go to your doctor’s office or the hospital for an ABG test. Your physician’s first step might be to check arterial blood flow in your wrist, using what’s known as a modified Allen test. If blood flow appears normal, he or she will draw blood from your arm using a needle. You’ll need to be free of any supplemental oxygen use for at least 20 minutes before the draw.

Blood gas levels and pH balances are derived from the following measures:

• Arterial blood pH: Blood pH records the volume of hydrogen ions, which is a variable for determining the blood’s degree of acidity. A healthy reading hovers around 7.4 pH, which is slightly base. Lower readings mean the blood is more acid, possibly indicating higher-than-normal carbon dioxide levels.
• Bicarbonate: Bicarbonate plays a critical role of maintaining blood pH inside a narrow interval of readings. A healthy bicarbonate value is 22 to 28 milliequivalents per liter.
• Partial oxygen pressure: Oxygen is critical to cellular respiration and other biological functions. Partial oxygen pressure measures the lung’s effectiveness at delivering oxygen to the bloodstream. A healthy reading is 75 to 100 mmHg (millimeters of mercury).
• Partial carbon dioxide (CO₂) pressure: Carbon dioxide is the waste gas left over from cellular respiration. Partial CO₂ pressure measures the lung’s effectiveness at extracting carbon dioxide from the blood, which is then eliminated from the body by exhalation. Healthy readings fall between 38 to 42 mmHg.
• Oxygen saturation: Oxygen saturation measures the volume of oxygen in the red blood cells. A healthy reading is 94 to 100 percent.

What Are the Possible Side Effects?

The primary side effects of an ABG test are those associated with the blood draw. Needle penetration is sometimes painful, and bruising is a possibility. 

What Is My Prognosis with Arterial Blood Gas Testing?

ABG tests are diagnostic tools for identifying the nature and severity of respiratory and other problems. Having good medical data will assist your physician in making appropriate determinations about your care, which is a key to managing your condition and improving long-term outlook.

When It Comes to Respiratory Health, We’re a Breath of Fresh Air

If you’re dealing with a respiratory ailment or condition, see your Baptist Health physician. He or she will be able to assess your condition and determine which medical treatments, if any, are most appropriate for you.