Nokea
The greatest quantity of air that can be expired after a maximum inspiratory effort is its
- A. Residual volume
- B. Tidal volume
- C. Vital capacity
- D. Lung volume
Correct Answer: C
Rationale: The correct answer is C: Vital capacity. Vital capacity is the maximum amount of air a person can expel from the lungs after a maximum inhalation. It is the sum of tidal volume, inspiratory reserve volume, and expiratory reserve volume. Residual volume (A) is the air left in the lungs after maximum exhalation. Tidal volume (B) is the amount of air inhaled and exhaled during normal breathing. Lung volume (D) is a general term and not a specific measure of air quantity. Thus, vital capacity is the best choice as it accounts for the maximum air that can be expired after a deep inhalation.
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A medical nurse has admitted a patient to the unit with a diagnosis of failure to thrive. The patient has developed a fever and cough, so a sputum specimen has been obtained. The nurse notes that the sputum is greenish and that there is a large quantity of it. The nurse notifies the patient's physician because these symptoms are suggestive of what?
- A. Pneumothorax
- B. Lung tumors
- C. Infection
- D. Pulmonary edema
Correct Answer: C
Rationale: The correct answer is C: Infection. The greenish color and large quantity of sputum suggest an infection in the lungs, typically caused by bacteria. Greenish sputum is often a sign of bacterial pneumonia. Fever and cough are common symptoms of a lung infection, along with increased sputum production. Pneumothorax (A) is characterized by a collapsed lung and does not typically present with greenish sputum. Lung tumors (B) may cause cough and sputum production, but the color of the sputum is not specific to tumors. Pulmonary edema (D) is a condition where fluid accumulates in the lungs, leading to shortness of breath and pink, frothy sputum, not greenish sputum.
After using a nasal cannula delivery system at 3 L/min, a patient with chronic airflow
limitation (CAL) changes to a simple face mask. The nasal equipment oxygen was set at 3
L/min. How should the nurse adjust the oxygen flow for the new delivery system?
- A. Decrease it to 2 L.
- B. Keep it the same.
- C. Increase it to 4 L.
- D. Increase it to 6 L.
Correct Answer: D
Rationale: To determine the correct oxygen flow for a simple face mask, you should increase it from the previous nasal cannula rate. As simple face masks deliver oxygen less efficiently, a higher flow rate is needed to maintain the same oxygen concentration. Moving from 3 L/min nasal cannula to a simple face mask, you should increase the flow to 6 L/min to ensure adequate oxygen delivery to the patient with chronic airflow limitation. Choices A and B are incorrect as decreasing or keeping the flow the same would not provide sufficient oxygen. Choice C is also incorrect as increasing it to 4 L/min may not be enough to compensate for the decreased efficiency of the simple face mask.
You are supervising a nursing student who is providing care for a thoracotomy client with a chest tube. What finding will you clearly instruct the nursing student to notify you about immediately?
- A. Chest tube drainage of 10-15 mL per hour
- B. Continuous bubbling in the water seal chamber
- C. Complaints of pain at the chest tube site
- D. Chest tube dressing dated yesterday.
Correct Answer: B
Rationale: The correct answer is B. Continuous bubbling in the water seal chamber indicates an air leak and potential complications. Drainage of 10-15 mL/hour (A) is normal. Pain complaints (C) and outdated dressing (D) are less urgent.
What is the role of alveolar macrophages?
- A. to secrete pulmonary surfactant
- B. to secrete antimicrobial proteins
- C. to remove pathogens and debris
- D. to facilitate gas exchange
Correct Answer: C
Rationale: The correct answer is C: to remove pathogens and debris. Alveolar macrophages are specialized immune cells located in the lungs responsible for engulfing and clearing pathogens, debris, and foreign particles. This function helps maintain lung health and prevents infections.
Rationale:
1. Alveolar macrophages are part of the immune system and act as the first line of defense in the lungs.
2. Their primary role is phagocytosis, engulfing and destroying pathogens and debris to protect the respiratory system.
3. Secreting pulmonary surfactant (choice A) is the function of type II alveolar cells, not alveolar macrophages.
4. While alveolar macrophages can secrete some antimicrobial proteins (choice B), their main function is phagocytosis.
5. Facilitating gas exchange (choice D) is the role of the alveoli and not specifically of alveolar macrophages.
In summary,
Partial pressure of O2 in the inspired air is 156 mm Hg and that of CO2 is
- A. 0.3 mm Hg
- B. 0.5 mm Hg
- C. 140 mm Hg
- D. 46 mmHg
Correct Answer: A
Rationale: Step-by-step rationale:
1. Inspired air has O2 partial pressure of 156 mm Hg.
2. In alveoli, O2 is exchanged with CO2.
3. CO2 partial pressure in alveoli is lower than in inspired air.
4. Therefore, CO2 partial pressure in inspired air must be much lower.
5. Choice A (0.3 mm Hg) is the only option significantly lower than O2 pressure, making it the correct answer.
Summary:
- Choice A is correct as it reflects the lower CO2 partial pressure compared to O2.
- Choices B, C, and D are incorrect as they do not show a significant difference in partial pressure compared to O2.