Elevated carbon dioxide levels in the blood is called:

A. Bradypnea and slow heart rate is incorrect because pulmonary embolism (PE) usually triggers tachypnea and tachycardia, not slow breathing or bradycardia. These responses occur as the body attempts to compensate for hypoxemia and reduced pulmonary blood flow.

B. Bilateral peripheral edema and generalized weakness is incorrect because bilateral leg swelling is more characteristic of heart failure or systemic venous congestion. While a PE may result from deep vein thrombosis (DVT), edema is usually unilateral and not the defining manifestation of an acute PE.

C. Sudden onset of dyspnea and sharp chest pain is correct because a pulmonary embolism occurs when a blood clot obstructs a pulmonary artery, causing abrupt impairment of blood flow to the lung. This leads to sudden shortness of breath, sharp or pleuritic chest pain (worsening with inspiration), tachypnea, and sometimes hemoptysis. Other signs may include anxiety, diaphoresis, and hypoxemia. Rapid recognition is essential, as PE can be life-threatening if untreated.

D. Gradual onset of a productive cough with thick sputum is incorrect because this pattern is more typical of pneumonia or chronic bronchitis, not pulmonary embolism. PE symptoms are typically acute and sudden rather than gradual.

A. Increased capillary permeability is correct because severe burns trigger an inflammatory response that damages the capillary walls. This damage allows plasma, proteins, and fluid to leak into the surrounding interstitial tissue, leading to edema. The combination of fluid shift and protein loss from the intravascular space causes hypovolemia and localized or generalized swelling. This phenomenon, known as burn shock or fluid shift, is a hallmark of major burn injuries.

B. Decreased metabolism of carbohydrates is incorrect because carbohydrate metabolism does not directly cause edema. While burn injuries can affect metabolic rate, the primary cause of fluid accumulation is vascular leakage, not metabolic dysfunction.

C. Decreased hematocrit in the blood is incorrect because hematocrit often increases initially after burns due to plasma loss into the interstitial space. Decreased hematocrit may occur later if fluid resuscitation dilutes the blood, but this is not the cause of edema.

D. Increased circulating blood volume is incorrect because circulating blood volume actually decreases in the acute phase of large burns due to plasma leakage. Edema occurs outside the blood vessels, not from an excess of blood within them.