Patients with respiratory failure commonly experience a rise in what level in arterial blood?

In cases of respiratory failure, patients typically have a compromised ability to either take in oxygen or eliminate carbon dioxide effectively. This leads to a retention of carbon dioxide in the bloodstream, causing its levels to rise. Elevated carbon dioxide levels, known as hypercapnia, occur when the respiratory system cannot remove carbon dioxide efficiently, which can result in respiratory acidosis and various physiological effects.

In contrast, the other options are not relevant to the conditions typically associated with respiratory failure. For instance, oxygen levels would often be low in respiratory failure rather than high. Hemoglobin levels can vary but are not directly affected in the same way by respiratory failure. Cholesterol levels are unrelated to the immediate effects of respiratory failure. Thus, the rise in carbon dioxide is a hallmark of respiratory failure, highlighting the importance of monitoring arterial blood gases in affected patients.