Abgs provide the following information. The p f ratio ratio between the pao 2 and the inspired oxygen concentration expressed as a fraction is a useful guide to the presence and severity of impaired.
Interpreting an abg is a crucial skill for health care professionals and it is especially important in critically ill patients.
Abg results uk. It provides a near immediate reflection of the physiology of your patient allowing you to recognise and treat pathology more rapidly. A base excess more than 2 meq l indicates a metabolic alkalosis. This guide will focus on a commonly used seven step process which helps ensure a complete interpretation of every abg.
An abg is a blood test that measures the acidity or ph and the levels of oxygen o2 and carbon dioxide co2 from an artery the test is used to check the function of the patient s lungs and how well they are able to move oxygen into the blood and remove carbon dioxide. Arterial blood gases abgs are an important routine investigation to monitor the acid base balance of patients. The first value is the ph which measures how many hydrogen ions h are in the sample.
14 11 13 kpa 105 mmhg 82 5 97 5 mmhg ph. An arterial blood gas test commonly known as an abg is performed on blood that is drawn from an artery it is used to see how well the lungs are functioning and to determine the effectiveness of respiratory therapies such as the use of a ventilator cpap bipap or oxygen a blood gas may also reveal the presence of kidney problems but is not typically performed to diagnose problems with the. From this baseline you can then begin to recognise significant variations in a patient s results which could indicate clinical deterioration.
7 49 7 35 7 45. What is an arterial blood gas abg. Arterial blood gas abg analysis is an essential part of diagnosing and managing a patient s gas exchange and acid base balance status and can also be useful in providing immediate information about electrolyte status.
An abg is performed and reveals the following. When interpreting abg results it is essential to know what abg values are considered normal. Interpretation of arterial blood gases requires a systematic assessment of oxygenation ph standard bicarbonate shco 3 and base excess partial pressure of carbon dioxide paco 2 and additional analytes.
Buffering system is the method by which the body controls ph and is crucial to understand arterial and venous blood gas results. In addition provided is a list of commonly encountered acid base disorders. An abg is performed on the patient who is not currently receiving any oxygen therapy.
They may help make a diagnosis indicate the severity of a condition and help to assess treatment. Many guides exist to aid the interpretation of the abg some may. Arterial blood gas interpretation can be a daunting and difficult skill for any medical student or junior doctor.
In terms of basic interpretation. A base excess less than 2 meq l indicates a metabolic acidosis. They have no significant past medical history and are not on any regular medication.
A value outside of the normal range 2 to 2 meq l suggests a metabolic cause for the acidosis or alkalosis.