Certified Respiratory Therapist Practice Exam

When obtaining an arterial sample for analysis using a point-of-care analyzer, it is essential to ensure the accuracy and integrity of the sample prior to analysis. Placing the sample in an ice slush is critical because it preserves the metabolic state of the blood. This is particularly important for arterial blood gas (ABG) analysis, as temperature influences the metabolism of the blood cells and can lead to altered results if the sample is left at room temperature.

By cooling the sample in an ice slush, you minimize cellular metabolism and maintain the sample’s pH, carbon dioxide, and oxygen levels closer to their physiological states at the time of collection. This is essential for obtaining reliable results that accurately reflect the patient’s respiratory and metabolic status.

In contrast, leaving the sample at room temperature could allow for changes in the gas composition and acid-base balance, which would compromise the test's validity. Analyzing the sample immediately without storage does indeed provide accurate results, but for practical purposes, especially in cases where immediate analysis isn't feasible, using ice slush serves as a more reliable method to maintain the sample’s integrity until it can be assessed. Storing in a sealed bag might protect the sample from contamination, but it does not address the critical issue of temperature control