Histotoxic hypoxia is classically caused by which toxin?

Unlock all questions

This demo includes only 20 questions. Upgrade to access hundreds of questions, flashcards, exam simulations, and disable ads.

Full question bankExam simulationsFlashcards
From $24.99Unlock all

Study for the Mechanical Vent 2 Exam 2. Prepare with flashcards and multiple-choice questions that include detailed explanations and hints. Ace your exam with confidence!

Multiple Choice

Histotoxic hypoxia is classically caused by which toxin?

Explanation:
Histotoxic hypoxia happens when tissues can’t use oxygen because a toxin disrupts cellular respiration. The classic culprit is cyanide, which blocks cytochrome c oxidase in the mitochondria. That stops oxidative phosphorylation, so even though oxygen is delivered to tissues, it can’t be used to produce ATP. Venous oxygen content remains high, and cells shift to anaerobic metabolism, leading to metabolic acidosis. Other options differ in mechanism: carbon monoxide reduces oxygen delivery by forming carboxyhemoglobin; nitrogen dioxide is mainly a pulmonary irritant with different effects; oxygen toxicity involves damage from high oxygen levels, not a failure of cellular oxygen use.

Histotoxic hypoxia happens when tissues can’t use oxygen because a toxin disrupts cellular respiration. The classic culprit is cyanide, which blocks cytochrome c oxidase in the mitochondria. That stops oxidative phosphorylation, so even though oxygen is delivered to tissues, it can’t be used to produce ATP. Venous oxygen content remains high, and cells shift to anaerobic metabolism, leading to metabolic acidosis.

Other options differ in mechanism: carbon monoxide reduces oxygen delivery by forming carboxyhemoglobin; nitrogen dioxide is mainly a pulmonary irritant with different effects; oxygen toxicity involves damage from high oxygen levels, not a failure of cellular oxygen use.

More Multiple Choice Questions
Subscribe

Get the latest from Examzify

You can unsubscribe at any time. Read our privacy policy