A patient breathing room air at sea level has the following arterial blood gases: PaO2 = 62 mm Hg; PCO2 = 75 mm Hg. When the FIO2 is raised to 0.28, the PaO2 rises to 95 mm Hg. What is the most likely cause of the hypoxemia?
a. Hypoventilation
b. Impaired diffusion
c. Right-to-left shunt
d. V/Q imbalance
ANS: A
In the case of simple hypoventilation, a rise in the alveolar PCO2 is always accompanied by a proportionate fall in alveolar PO2. The P(A–a)O2 is normal in such cases. The hypoxemia will re-spond readily to O2 therapy.
You might also like to view...
Continuing education for the RMA is available through which of the following publications?
a. Professional Medical Assistant b. Journal of Continuing Education Topics & Issues c. STEP Continuing Education d. CMA Today
Which of the following prefixes means "slow"?
brady- peri- tachy- intra-
Which of the following are indications for arterial blood gas analysis according to the American Association for Respiratory Care (AARC) Clinical Practice Guideline: Blood Gas Analysis and Hemoximeter: 2001 Revision and Update? I. Assess a patient's ventilatory status. II. Assess a patient's acid-base status. III. Assess a patient's oxygenation status. IV. Monitor response to therapeutic
intervention. A) I B) I and II C) I, II, and III D) I, II, III, and IV
A nurse recalls that the most frequent location of a neuroblastoma is the:
a. retroperitoneal region. b. mediastinum. c. cervical ganglion. d. lung.