ATI RN
Questions for Respiratory System Questions
Question 1 of 5
What is the primary function of carbonic anhydrase in the human body?
Correct Answer: D
Rationale: The correct answer is D: Catalyzing the conversion of carbon dioxide and water to bicarbonate and hydrogen ions. Carbonic anhydrase helps maintain acid-base balance in the body by catalyzing the reversible reaction between carbon dioxide and water to form bicarbonate and hydrogen ions. This process is crucial in regulating pH levels in various bodily fluids. A: Breakdown of carbohydrates - This is not the primary function of carbonic anhydrase. Carbohydrate breakdown is primarily carried out by enzymes like amylase and sucrase. B: Regulation of blood sugar levels - Carbonic anhydrase does not play a direct role in regulating blood sugar levels, which is mainly controlled by insulin and glucagon. C: Facilitation of gas exchange in the lungs - While carbonic anhydrase indirectly affects gas exchange by regulating blood pH, its primary function is not to facilitate gas exchange in the lungs.
Question 2 of 5
A nurse reviews the arterial blood gas results of a client and notes the following: pH 7.45, PCO2 30, HCO3 20. The nurse analyzes these results as indicating which condition?
Correct Answer: B
Rationale: The correct answer is B: Respiratory alkalosis, fully compensated. The pH is elevated (alkalosis) at 7.45. The low PCO2 of 30 indicates respiratory alkalosis. The HCO3 level of 20 is slightly below normal, indicating metabolic compensation. The body has compensated for the respiratory alkalosis by reducing the HCO3 level. Choices A, C, and D are incorrect because they do not align with the given ABG results. A (Metabolic acidosis, compensated) would have low pH and HCO3 levels. C (Metabolic alkalosis, uncompensated) would have high pH and HCO3 levels. D (Respiratory acidosis, uncompensated) would have high PCO2 and low pH.
Question 3 of 5
All of the following shift the oxygen dissociation curve to the right EXCEPT
Correct Answer: C
Rationale: The correct answer is C: Carbon monoxide. Carbon monoxide binds to hemoglobin with a higher affinity than oxygen, shifting the oxygen dissociation curve to the left, not the right. Decreased pH, increased temperature, and increased 2,3 DPG all shift the curve to the right by decreasing hemoglobin's affinity for oxygen. This results in easier unloading of oxygen to tissues.
Question 4 of 5
Before administering ephedrine, Nurse Tony assesses the patient's history. Because of ephedrine's central nervous system (CNS) effects, it is not recommended for:
Correct Answer: D
Rationale: The correct answer is D: Elderly patients. Ephedrine, a sympathomimetic amine, can exacerbate existing CNS conditions in elderly patients, leading to adverse effects like confusion, agitation, and increased risk of falls. Elderly patients are more sensitive to CNS stimulants due to age-related changes in drug metabolism and clearance, making them more susceptible to negative effects. Choices A, B, and C are incorrect because patients with acute asthma attacks may benefit from ephedrine's bronchodilator effects, patients with narcolepsy may benefit from its stimulant properties, and age alone is not a contraindication for ephedrine use.
Question 5 of 5
A nurse instructs a female client to use the pursed-lip method of breathing and the client asks the nurse about the purpose of this type of breathing. The nurse responds, knowing that the primary purpose of pursed-lip breathing is to:
Correct Answer: D
Rationale: The correct answer is D: Promote carbon dioxide elimination. Pursed-lip breathing is a technique used to slow down breathing and help control shortness of breath. By exhaling through pursed lips, it creates back-pressure in the airways, allowing more time for the lungs to empty and facilitating better removal of carbon dioxide. This helps improve oxygenation by optimizing the gas exchange process. Choices A, B, and C are incorrect because pursed-lip breathing primarily focuses on improving ventilation and gas exchange, not specifically on increasing oxygen intake or strengthening specific respiratory muscles.