42. A nurse should know that the oxygen flow rate set for clients with emphysema is usually low because:
42. A nurse should know that the oxygen flow rate set for clients with emphysema is usually low because:
. Low flow rates enhance ventilation-perfusion (V/Q) ratios.
. Higher flow rates can depress the hypoxic drive.
. Low flow rates are palliative and relieve anxiety.
. O2 prevents compensatory respiratory alkalosis.
Test-Taking Tip
Selecting the correct answer requires knowing the stimulus to breathe in emphysema. Focus on the one option that states an undesirable effect ("depress the hypoxic drive").
Content Area: Adult Health, Respiratory; Integrated Process: Nursing Process, Planning; Cognitive Level: Application; Client Need/Subneed: Physiological Integrity/Reduction of Risk Potential/Therapeutic Procedures
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Answer 1 is incorrect because the V/Q abnormality is related to the disease process and cannot be corrected with O2. Answer 2 is correct because clients with emphysema suffer from chronically high CO2 levels, so the normal CO2 stimulus is ineffective. The stimulus is the low O2—a hypoxic drive. Answer 3 is incorrect because it does not answer the question. Supplemental O2 is not curative; it does make the client feel better, which may be palliative, but the choice of a flow rate is purposeful. Answer 4 is incorrect because the compensation that occurs in response to respiratory acidosis is a metabolic alkalosis.