Nokea
The oxygen content of air is approximately
- A. 21 percent.
- B. 78 percent.
- C. 0.04 percent
- D. 0.96 percent.
Correct Answer: A
Rationale: The correct answer is A: 21 percent. Air is composed of about 21% oxygen, 78% nitrogen, and small amounts of other gases. This composition is crucial for sustaining life on Earth. Choice B is incorrect as it represents the percentage of nitrogen in the air. Choices C and D are also incorrect as they are the approximate percentages of carbon dioxide and argon in the air, respectively. Therefore, the correct answer is A as it accurately reflects the oxygen content in the air.
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Which of the following is an important preventive factor that the nurse should teach a client with rhinitis?
- A. Not to blow the nose
- B. Consume small doses of ice chips
- C. Not to lift objects weighing more than 5 to 10 lbs
- D. Wash hands frequently
Correct Answer: D
Rationale: The correct answer is D. Washing hands frequently is crucial to prevent the spread of infections that can exacerbate rhinitis. A (not to blow the nose) is impractical and unnecessary. B (consuming ice chips) has no preventive value. C (not lifting heavy objects) is unrelated to rhinitis prevention.
A client is wearing a Venturi mask to deliver oxygen and the dinner tray has arrived. What action by the nurse is best?
- A. Assess the client's oxygen saturation and, if normal, turn off the oxygen.
- B. Determine if the client can switch to a nasal cannula during the meal.
- C. Have the client lift the mask off the face when taking bites of food.
- D. Turn the oxygen off while the client eats the meal and then restart it.
Correct Answer: B
Rationale: The correct answer is B. Switching to a nasal cannula during meals allows the client to eat comfortably while still receiving oxygen. This ensures proper oxygenation during meals without compromising nutrition. Option A is incorrect because oxygen should not be turned off without a healthcare provider's order. Option C is incorrect as lifting the mask can reduce oxygen delivery. Option D is incorrect as oxygen should not be turned off abruptly. Switching to a nasal cannula is the safest and most appropriate option for clients using a Venturi mask during meals.
The nurse teaches the client that sublingual nitroglycerin should be taken
- A. Every two to three hours during the day
- B. At the first indication of chest pain
- C. Before every meal and at bedtime
- D. Only after 911 is called first
Correct Answer: B
Rationale: The correct answer is B - "At the first indication of chest pain." This is because sublingual nitroglycerin is a rapid-acting medication used to relieve chest pain related to angina by dilating blood vessels. Taking it at the first sign of chest pain ensures prompt relief. Choice A is incorrect as frequent dosing can lead to tolerance. Choice C is unnecessary and not evidence-based. Choice D delays treatment and can be dangerous in an emergency.
In human beings, CO2 concentration in the inspired and expired air is respectively
- A. 0.03 % and 5.3 %
- B. 0.4 % and 5.0 %
- C. 0.04 % and 3.0 %
- D. 0.03 % and 4.0 %
Correct Answer: D
Rationale: The correct answer is D (0.03% and 4.0%). The inspired air contains approximately 0.03% CO2, as the atmosphere has a low CO2 concentration. During expiration, the CO2 concentration in the air increases due to the removal of oxygen and the addition of CO2 from cellular respiration, resulting in an average of around 4.0% CO2 in expired air. Choices A, B, and C are incorrect because they do not accurately reflect the typical CO2 concentrations in inspired and expired air in human beings.
A pulmonary embolus is suspected in a patient with a deep vein thrombosis who develops hemoptysis, tachycardia, and chest pain. Diagnostic testing is scheduled. Which test should the nurse plan to teach the patient about?
- A. Chest x-rays
- B. Spiral (helical) CT scan
- C. Take the patient’s pulse and blood pressure.
- D. Ventilation-perfusion lung scan
Correct Answer: B
Rationale: A Spiral (helical) CT scan is the most appropriate diagnostic test for suspected pulmonary embolism as it provides detailed imaging of the pulmonary arteries, allowing for visualization of blood clots.