What hypersensitivity reaction occurs when a person has a skin reaction to poison ivy?

Choice A reason: Overinflated alveoli and air trapping occur in emphysema or COPD, not atelectasis. Atelectasis involves alveolar collapse, reducing lung volume and gas exchange, not overinflation, making this choice incorrect for the pathophysiology of atelectasis.

Choice B reason: Atelectasis is the collapse of alveoli, often due to obstruction, compression, or surfactant deficiency, impairing ventilation and perfusion. This reduces gas exchange, causing hypoxia, and matches the pathophysiological process, making this the correct choice for atelectasis.

Choice C reason: Inflammation of the bronchi (bronchitis) involves airway inflammation, not alveolar collapse. Atelectasis results from physical collapse of alveoli, not primarily inflammatory processes, making this choice incorrect for atelectasis’s pathophysiology.

Choice D reason: Inflammatory congestion in alveoli describes pneumonia or pulmonary edema, not atelectasis. Atelectasis involves alveolar collapse, reducing ventilation without primary inflammation or fluid accumulation, making this choice incorrect for the described process.

Choice A reason: Red warm skin is not typical of pulmonary embolism. It may occur in infections or inflammation. Pulmonary embolism causes reduced lung perfusion, leading to hypoxia and systemic symptoms, not localized skin changes, making this choice incorrect.

Choice B reason: Dizziness occurs in pulmonary embolism due to reduced oxygen delivery to the brain from blocked pulmonary arteries, causing hypoxia. Decreased cardiac output from right heart strain also contributes, making this a correct manifestation of pulmonary embolism.

Choice C reason: Bradycardia is not typical; pulmonary embolism usually causes tachycardia as the heart compensates for hypoxia and increased pulmonary vascular resistance. Slow heart rate does not align with the body’s response to acute obstruction, making this incorrect.

Choice D reason: Hypoxia is a hallmark of pulmonary embolism, as blocked pulmonary arteries impair gas exchange, reducing oxygen in the blood. This leads to tissue oxygen deficiency, causing symptoms like shortness of breath, making this a correct manifestation.

Choice E reason: Chest pain in pulmonary embolism results from pleural irritation or ischemia due to blocked pulmonary arteries. The pain is often sharp and worsens with breathing, reflecting lung tissue stress, making this a correct manifestation.

Choice F reason: Tachypnea, or rapid breathing, occurs as the body attempts to compensate for hypoxia in pulmonary embolism. The respiratory system increases rate to improve oxygenation, a common response to impaired gas exchange, making this correct.