LPN exams respiratory practice questions set 11

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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,

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The correct answer is D: diffusion. Oxygen and carbon dioxide move in and out of cells through simple diffusion, which is the passive movement of molecules from an area of high concentration to an area of low concentration. This process occurs due to the concentration gradient of these gases. Osmosis (Choice C) is the movement of water across a selectively permeable membrane, not gases like oxygen and carbon dioxide. Exocytosis and endocytosis (Choice A) involve the transport of larger molecules and particles in and out of cells, not gases. Bulk flow (Choice B) involves the movement of fluids in response to pressure differences, not the specific movement of oxygen and carbon dioxide molecules. Therefore, diffusion is the correct mechanism for the movement of oxygen and carbon dioxide in the body due to their small molecular size and the concentration gradient present.

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Per Fick's law (Rate = A × D × ΔP / d), diffusion decreases if surface area (A) drops (e.g., emphysema destroys alveoli, halving A halves rate), diffusion distance (d) increases (e.g., pulmonary edema doubles d from 0.5 to 1 μm, halving rate), or partial pressure gradient (ΔP) falls (e.g., hypoventilation lowers alveolar PO2). Decreased pressure coefficient' likely means ΔP; reducing it (e.g., from 60 to 30 mmHg) slows diffusion. Increased lung fluid thickens the barrier, adding resistance beyond distance (e.g., protein debris). All factors reduced A, increased d, lowered ΔP independently and collectively cut diffusion, as seen in hypoxemia from edema or fibrosis. Diffusion coefficient (D) is unchanged here. Each aligns with clinical scenarios impairing O2 transfer, making all the above' correct, reflecting multiple pathways to reduced gas exchange efficiency.

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Correct Answer: A - Increase in volume of thoracic cavity and fall in lung pressure Rationale: 1. During inspiration, the diaphragm contracts and moves downward, increasing the volume of the thoracic cavity. 2. The external intercostal muscles also contract, lifting the ribcage and further expanding the thoracic cavity. 3. As thoracic cavity volume increases, lung pressure decreases, creating a pressure gradient that allows air to flow into the lungs. Summary: B: Fall in pressure inside the lungs - This is a consequence of the increase in thoracic cavity volume, not the cause of air entering the lungs. C: Increased volume of thoracic cavity - This is correct but does not explain how air enters the lungs. D: Muscular expansion of lungs - Lungs do not expand on their own; it is the thoracic cavity that expands to create the pressure gradient for air entry.

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The correct answer is B: Chronic obstructive pulmonary disease (COPD). The patient's smoking history, dyspnea, anxiety, chronic cough with sputum production, and barrel-shaped chest are indicative of COPD. Smoking is the primary cause of COPD, leading to airway inflammation and airflow limitation. The dyspnea, cough, and sputum production are common symptoms of COPD due to air trapping and mucus hypersecretion. The barrel-shaped chest is a sign of hyperinflation of the lungs seen in COPD patients. Pneumonia (A) typically presents with symptoms like fever and productive cough, not necessarily dyspnea and barrel chest. Tuberculosis (C) commonly presents with weight loss, night sweats, and hemoptysis, not the symptoms described. Asthma (D) often presents with wheezing, chest tightness, and reversible airflow obstruction, not the chronic symptoms described in this case.

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A sore muscle at the injection site is a common adverse reaction to the influenza vaccine, occurring due to local inflammation from the needle and immune response activation. It's typically mild, lasting a day or two, and aligns with expected side effects reported by the CDC. Rhinorrhea and low-grade fever are more associated with the live attenuated nasal spray vaccine, not the inactivated injectable form most adults receive. Hives and numbness suggest an allergic reaction, which is rare and requires immediate attention, not routine teaching. Malaise and myalgia can occur but are less frequent and specific than injection-site soreness. The nurse includes this reaction in teaching to prepare the client for a normal, self-limiting response, reducing anxiety and ensuring they distinguish it from severe symptoms needing medical follow-up, promoting vaccine acceptance.

Correct answer:

A sore muscle at the injection site is a common adverse reaction to the influenza vaccine, occurring due to local inflammation from the needle and immune response activation. It's typically mild, lasting a day or two, and aligns with expected side effects reported by the CDC. Rhinorrhea and low-grade fever are more associated with the live attenuated nasal spray vaccine, not the inactivated injectable form most adults receive. Hives and numbness suggest an allergic reaction, which is rare and requires immediate attention, not routine teaching. Malaise and myalgia can occur but are less frequent and specific than injection-site soreness. The nurse includes this reaction in teaching to prepare the client for a normal, self-limiting response, reducing anxiety and ensuring they distinguish it from severe symptoms needing medical follow-up, promoting vaccine acceptance.

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The correct answer is D: Contralateral side in hemothorax. In a hemothorax, blood collects in the pleural cavity on one side of the chest, causing a mass effect that displaces the trachea away from the affected side towards the opposite side. This occurs due to the pressure created by the accumulated blood pushing the trachea away. In the other choices, tracheal deviation would occur towards the affected side rather than away from it. For example, in a tension pneumothorax (Choice C), air accumulates under pressure in the pleural space, causing the lung to collapse and pushing the trachea towards the affected side. Similarly, in a simple pneumothorax (Choice A), where there is air in the pleural space but not under pressure, the trachea may deviate towards the affected side. In a hemothorax (Choice B), the trachea would not deviate towards the affected side as

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The inspiratory capacity is the maximum volume of air that can be inhaled after a normal exhalation. It is the sum of tidal volume and inspiratory reserve volume. Tidal volume is the volume of air inhaled and exhaled during normal breathing, while inspiratory reserve volume is the additional air that can be inhaled after a normal inhalation. Therefore, the correct answer is A. Summary of why other choices are incorrect: B: Vital capacity is the maximum volume of air that can be exhaled after a maximum inhalation. It does not include tidal volume, so this choice is incorrect. C: Vital capacity includes inspiratory reserve volume, not tidal volume, so this choice is incorrect. D: Residual volume is the volume of air remaining in the lungs after maximal exhalation, not part of inspiratory capacity. Tidal volume is the only correct component in this choice.

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In a severe asthma attack, bronchoconstriction obstructs airways, reducing airflow, especially on expiration, causing wheezing. FEV1/FVC decreases (<80%) as FEV1 drops more than FVC due to obstruction, not increases. The ventilation/perfusion (V/Q) ratio in affected areas falls, as ventilation is blocked while perfusion persists, causing hypoxemia (PaO2 60 mmHg vs. 75-100 mmHg normal). Arterial PCO2 (30 mmHg vs. 35-45 mmHg) is lower, not higher, because hypoxemia stimulates hyperventilation via peripheral chemoreceptors, expelling CO2 faster than it builds up, a compensatory response in acute asthma. Inadequate gas exchange lowers PaO2, not PCO2, here. Option D correctly ties low PCO2 to hyperventilation driven by hypoxia, aligning with asthma's physiology where obstruction impairs oxygen uptake but CO2 clearance accelerates with increased respiratory effort.