An arterial-blood gas (ABG) test measures the amounts of arterial gases, such as oxygen and carbon dioxide. An ABG test requires that a small volume of blood. An arterial blood gas test can find ways to help your lungs do their job. Find out when you get it and what the results mean. 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.

Author: Mezijar Shashakar
Country: Liberia
Language: English (Spanish)
Genre: Finance
Published (Last): 7 December 2007
Pages: 30
PDF File Size: 19.29 Mb
ePub File Size: 18.25 Mb
ISBN: 728-8-15320-375-8
Downloads: 18459
Price: Free* [*Free Regsitration Required]
Uploader: Niramar

This causes the HCO 3 -: Measured parameters Partial pressure of oxygen PaO 2 and partial pressure of carbon dioxide PaCO 2 in arterial blood pH Base excess ; and standard bicarbonate Modern blood gas analyzers also measure: Abstract Disorders of atrerial balance can lead to severe complications in many disease states, and occasionally the abnormality may be so severe as to become a life-threatening risk factor.

Nil Conflict of Interest: The most common problems that are encountered include fasometry samples, air bubbles in the sample, inadequate or excessive anticoagulant in the sample, and delayed analysis of a noncooled sample.

Interpretation of arterial blood gas

Principles of Pulmonary Medicine. The hydrogen ion is calculated by subtracting the two digits after the decimal point of pH from 80, e.

Blood gases, arterial ABG – blood. Mixed Disorder—if HCO 3 – and paCO 2 change in opposite direction which they normally should notthen it is a mixed disorder: Yearbook of Intensive Care and Emergency Medicine.

There is no special preparation. Calculate the expected paO 2 generally five times the FiO 2.

Arterial blood gas test – Wikipedia

The sealed syringe is taken to a blood gas analyzer. SaO2 is derived from the measured PO2 and calculated based on the assumption that all measured hemoglobin is normal oxy- or deoxy- hemoglobin. An arterial-blood gas ABG test measures the amounts of arterial gases, such as oxygen and carbon dioxide.


How to Prepare for the Test. This is familiarly known as anion gap AGwhen normal concentration is actually caused by A. Simple and mixed acid-base disorders: A low PaO 2 indicates that the person is not oxygenating properly, and is hypoxemic.

Any air bubble in the sample must be expelled as soon as possible after withdrawing the sample and before mixing with heparin or before any cooling of the sample has been done. This article has been cited by other articles in PMC. Table 3 Description of the species of unmeasured anions, source of origin, and diagnostic adjuncts in case of high anion gap metabolic acidosis.

gasomehry In some cases, blood from a vein may be used. When the needle is inserted to draw blood, some people feel moderate pain. When analysis is expected to be delayed for more than 30 minutes, use of glass syringes and ice slurry is recommended.

In patients with metabolic acidosis, an excess of acid or loss of base is present. Syringes for blood gas analysis can have a wide range of gaspmetry amounts.

The following six-step process helps ensure a complete interpretation of every ABG.

The test is negative and considered pathological if the patient’s hand remains at least partially pale. Tobacco Control Tuberculosis Washington Letter. It is recommended to mix the blood sample thoroughly by inverting the syringe aeterial times and rolling it between the palms as shown in Figure 1.

Selected causes of metabolic alkalosis. Pulse oximetry provides falsely high values in cases of carbon monoxide poisoningas complexes of hemoglobin and carbon monoxide are indistinguishable from oxygen-hemoglobin complexes!


National Committee for Clinical Laboratory Standards. Is the disturbance respiratory or metabolic? Respiratory acidosis would occur in COPD, muscular weakness, postoperative cases, and opioid overdose, and respiratory alkalosis is likely to occur in sepsis, hepatic coma, and pregnancy. Interpretation Hypoxemic respiratory failure type 1 respiratory failure: The blood can also be drawn from an arterial catheter.

Arterial blood gas test

Selected mixed and complex acid-base disturbances. Thus when an arterial blood gas test reveals, for example, an elevated bicarbonate, the problem has been present for a couple of days, and metabolic compensation took place over a blood acedemia problem. Find hundreds of Learning Cards covering all clinical subjects Practice answering thousands of USMLE-formatted multiple choice questions in the Qbank Explore concepts in depth with interactive images, videos and charts Fill knowledge gaps with the help of supportive features and an analysis of your progress.

If the user draws 2 mL of blood, then the resulting gasometrj concentration will be too low and the sample may coagulate.

The provider inserts a small needle through the skin into the artery. High AG versus normal AG metabolic acidosis. Arterial blood gas levels after oxygen therapy.

The usefulness of this diagnostic tool is dependent on being able to correctly interpret the results. Lung Gasommetry Week Contamination of the sample with room air will result in abnormally low carbon dioxide and possibly elevated oxygen levels, and a concurrent elevation in pH.

Retrieved from ” https: Respiratory compensation occurs faster than metabolic compensation. Clinical and Laboratory Standards Institute. How the Test will Feel. Footnotes Source of Support: