Are you looking for an ABG Calculator that can make Acid-Base Balance analysis easy? If so, you’re in the right place because we built one just for you. Our ABG Calculator is designed to help make the learning process for ABG Interpretation much easier.

Keep in mind, this calculator was built only for practice problems. It should never be used in the clinical setting. Please read the medical disclaimer before proceeding. 

Medical Disclaimer: This calculator is not intended to be used for professional medical advice, diagnosis, or treatment. The authors make no claims of the accuracy of the information contained herein. Please consult with a physician with any questions that you may have regarding a medical condition. This calculator is for educational purposes only — not for medical use. All calculations must be confirmed before use.

ABG Interpretation Calculator:

ABG Calculator

(Arterial Blood Gas Values)
pH
mm Hg
mEq/L

ABG Calculator

(Arterial Blood Gas Values)
pH
mm Hg
mEq/L

ABG Normal Values:

  • pH: 7.35-7.45
  • Partial Pressure of Oxygen (PaO2): 75-100 mmHg
  • Partial Pressure of Carbon Dioxide (PaCO2): 35-45 mmHg
  • Bicarbonate (HCO3-): 22-26 mEq/L
  • Oxygen Saturation (SpO2): 94-100%

What is an Arterial Blood Gas?

An Arterial Blood Gas, or ABG for short, is a test that measures the blood levels of oxygen (PaO2), carbon dioxide (PaCO2), and acid-base balance (pH) in the body. The test results are used by medical professionals to assess how well oxygen is being distributed throughout the body and how well carbon dioxide is being removed.

This is why ABG Interpretation is so important. You can use the ABG Calculator above as a shortcut to make the learning process much easier.

What is an Arterial Blood Gas Calculator?

An ABG Calculator, like the one above, is a piece of software that can be used to quickly calculate the interpretation of a sample set of ABG results. It’s designed to help students master ABG Interpretation. 

Just a reminder, it should be used for learning and practicing only and is not intended to be used in a real-life clinical setting.

Steps for Performing and ABG Analysis:

  • Step 1 – Obtain and Run the ABG Sample 
  • Step 2 – Determine if the pH is Alkalosis or Acidosis
  • Step 3 – Determine if the Issue is Respiratory or Metabolic
  • Step 4 – Determine if it’s Compensated or Uncompensated

The ABG Calculator can help you with this process but it’s best if you learn to perform an ABG Analysis on your own. This will get easier the more you practice. Be sure to read our complete guide on Arterial Blood Gases.

What is Acid-Base Balance?

Acid-Base Balance refers to the degree of acidity or alkalinity in the human body which is measured by the pH scale. The pH scale ranges from 0, which is very acidic, to 14, which is very alkaline.

Human blood is typically slightly more alkaline than acidic and a normal pH ranges from 7.35 to 7.45. Our body strives to maintain the blood pH as close to 7.40 as possible.

Respiratory Therapists, doctors, and medical professionals can evaluate a patient’s acid-base balance by measuring the levels of carbon dioxide and bicarbonate in arterial blood.

This test is called an Arterial Blood Gas (ABG).

Acid-Base Balance is controlled by the lungs, kidneys, and buffer systems. The lungs help with ventilation and oxygenation by providing the blood with oxygen and removing carbon dioxide on exhalation.

The kidneys help to regulate blood pH by excreting acids or bases in order to maintain a proper balance. Buffer systems help maintain proper pH balance by guarding against sudden swings in acidity and alkalinity.

Types of Acid-Base Disorders:

There are two types of abnormalities when it comes to maintaining Acid-Base Balance:

  1. Acidosis
  2. Alkalosis

Acidosis means that the blood has either too much acid, or too little bases, which results in a decreased pH. Alkalosis means that the blood has too much base, or too little acid, which results in a decreased pH.

There are also two types of Acid-Base Disorders:

  1. Respiratory
  2. Metabolic

Metabolic acidosis or alkalosis occurs when there is an imbalance in the production of acids or bases that results from a lack of excretion by the kidneys.

Respiratory acidosis or alkalosis occurs when the lungs are removing too much or too little carbon dioxide due to breathing disorders.

Respiratory Acidosis:

 pHPaCO2HCO3
Acute (Uncompensated)< 7.35> 45Normal
Partially Compensated< 7.35> 45> 26
Chronic (Fully Compensated)Normal> 45> 26

Respiratory Alkalosis:

 

pH

PaCO2

HCO3

Acute (Uncompensated)

> 7.45

< 35

Normal

Partially Compensated

> 7.45

< 35

< 22

Chronic (Fully Compensated)

Normal

< 35

< 22

Metabolic Acidosis:

 

pH

PaCO2

HCO3

Acute (Uncompensated)

< 7.35

Normal

< 22

Partially Compensated

< 7.35

< 35

< 22

Chronic (Fully Compensated)

Normal

< 35

< 22

Metabolic Alkalosis:

 

pH

PaCO2

HCO3

Acute (Uncompensated)

> 7.45

Normal

> 26

Partially Compensated

> 7.45

> 45

> 26

Chronic (Fully Compensated)

Normal

> 45

> 26

Final Thoughts

So there you have it. Now you should have a better understanding of Acid-Base Balance and hopefully our ABG Interpretation Calculator was helpful for you.

Just a reminder, it should be used for practice problems only. Never rely on an ABG Calculator in a real-life clinical setting. Thank you so much for reading and as always, breathe easy my friend.

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References

The following are the sources that were used while doing research for this article:

  • “Interpretation of Arterial Blood Gas.” PubMed Central (PMC), Apr. 2010, www.ncbi.nlm.nih.gov/pmc/articles/PMC2936733.
  • “Diagnosing Metabolic Acidosis in the Critically Ill: Bridging the Anion Gap, Stewart, and Base Excess Methods.” PubMed, 1 Mar. 2009, pubmed.ncbi.nlm.nih.gov/19247746.
  • Rose, Burton, and Theodore Post. Clinical Physiology of Acid-Base and Electrolyte Disorders (Clinical Physiology of Acid Base & Electrolyte Disorders). 5th ed., McGraw-Hill Education / Medical, 2001. [Link]
  • Faarc, Kacmarek Robert PhD Rrt, et al. Egan’s Fundamentals of Respiratory Care. 11th ed., Mosby, 2016. [Link]

Disclosure: The links to the textbooks are affiliate links which means, at no additional cost to you, we will earn a commission if you click through and make a purchase.