An oxygen delivery system is prescribed for a client with chronic obstructive pulmonary disease to deliver a precise oxygen concentration. Which of the following types of oxygen delivery systems would the nurse anticipate to be prescribed?

Correct Answer: B

Rationale: The correct answer is B: Venturi mask. The Venturi mask delivers a precise oxygen concentration by mixing oxygen with room air through different sized ports, allowing for accurate oxygen delivery. This is important for patients with COPD who require specific oxygen levels to prevent oxygen toxicity or hypoxemia. A: Face mask delivers a less precise oxygen concentration and may not be suitable for patients who require exact oxygen levels. C: Aerosol mask is used for delivering medications or humidified air, not for precise oxygen concentration. D: Tracheostomy collar is used for patients with a tracheostomy and is not typically used for delivering precise oxygen concentration in COPD.

Correct Answer: C

Rationale: The correct answer is C: larynx. When you swallow, the epiglottis covers the opening to the larynx to prevent food or liquid from entering the airway and instead directs it towards the esophagus. The epiglottis acts as a protective mechanism to ensure that food goes down the correct pathway. Choices A (pharynx), B (esophagus), and D (bronchus) are incorrect because the epiglottis does not directly cover the opening to these structures during swallowing. The epiglottis specifically functions to protect the larynx and the airway during the swallowing process.

Correct Answer: A

Rationale: The correct answer is A because oxygen moves from alveoli to the bloodstream by simple diffusion. This is due to the concentration gradient of oxygen being higher in the alveoli (where oxygen is inhaled) compared to the blood vessels surrounding the alveoli. Oxygen molecules move from an area of high concentration (alveoli) to an area of low concentration (bloodstream) to reach equilibrium. Choices B, C, and D are incorrect because the movement of oxygen in this context is primarily driven by passive diffusion, not by the activity of carbonic anhydrase, carbaminohemoglobin, or active transport.

Correct Answer: B

Rationale: The correct answer is B: as oxyhemoglobin. Oxygen is primarily carried in the blood by binding to hemoglobin in red blood cells to form oxyhemoglobin. This allows for efficient transport of oxygen to tissues. Choice A is incorrect because only a small amount of oxygen is dissolved in plasma. Choice C is incorrect as carboxyhemoglobin refers to carbon monoxide binding to hemoglobin, not oxygen. Choice D is incorrect as the majority of carbon dioxide is transported as bicarbonate, not oxygen.

Correct Answer: B

Rationale: The correct answer is B: Residual volume. After maximum forceful expiration, residual volume is the volume of air left in the lungs to prevent lung collapse. Total lung capacity (A) is the maximum amount of air the lungs can hold. Vital capacity (C) is the maximum amount of air that can be exhaled after a maximum inhalation. Tidal volume (D) is the volume of air moved in and out of the lungs during normal breathing, not after a forceful expiration.