Certified Pulmonary Function Technologist (CPFT) Practice Exam

A blood gas analyzer that employs Mylar is primarily used for measuring what?

1. The partial pressure of carbon dioxide (PCO2)

2. The partial pressure of oxygen (PO2)

3. Acid-base balance (pH)

4. Carbon monoxide levels

The correct answer is: The partial pressure of oxygen (PO2)

A blood gas analyzer that employs Mylar is primarily utilized for measuring the partial pressure of oxygen (PO2). Mylar is a type of polyester film that is commonly used in the construction of certain sensors within blood gas analyzers. These sensors are designed to measure oxygen levels in arterial blood since accurate measurement of oxygen is crucial for assessing a patient’s respiratory status and overall metabolic function. When blood passes over the sensor coated with Mylar, its unique properties allow for precise detection of the amount of oxygen dissolved in the blood. This information is vital for diagnosing conditions such as hypoxemia, where there is an abnormally low level of oxygen in the blood, and it helps guide treatment decisions in critical care settings. Differentiating characteristics of the other measurement goals are that while PCO2 and pH are also critical for evaluating blood gas status, they do not typically involve Mylar-based technology in the same way PO2 measurement does. Similarly, carbon monoxide levels are measured using different methodologies, often involving co-oximeters rather than the typical blood gas analyzer setup. Thus, the correct answer specifically highlights the method and context in which Mylar is applied in blood gas analysis.