Factors Modifying the Accuracy of ABG Results
Arterial blood gases (ABGs) are necessary for the investigation, monitoring and clarification of mechanisms of gas exchange, and of acid–base disorders. The design of the electrodes in the blood gas analyser is based on the model of the electro-chemical cell. Two half-cells are immersed in an electrolyte solution. An external connection which includes an ammeter completes the circuit. Chemical reactions that consume electrons occur at each half-cell in solution. The half-cell at which the stronger of the two reactions occurs, becomes the cathode; the other half cell (which is therefore negative relative to the first half-cell) becomes the anode.