In addition to heart rate, blood pressure, respiratory rate, and temperature, the nurse needs to assess a patient's arterial oxygen saturation (SaO2). What procedure will best accomplish this?

Correct Answer: D

Rationale: Step 1: Pulse oximetry is a non-invasive method of measuring SaO2 by using a sensor attached to a patient's fingertip, earlobe, or toe. Step 2: It provides immediate and continuous monitoring of oxygen saturation levels in the blood, making it an efficient and reliable method. Step 3: Pulse oximetry is widely used in clinical settings due to its accuracy and convenience. Step 4: In contrast, the other options are not direct methods for assessing SaO2. Incentive spirometry helps improve lung function, ABG measures blood pH and gases, and peak flow measures airflow in the lungs.

Correct Answer: D

Rationale: During hyperpnea, which is increased rate and depth of breathing, both inspiration and expiration require muscular contractions. Inspiration involves the diaphragm contracting and external intercostal muscles expanding the rib cage, while expiration involves the internal intercostal muscles contracting to decrease the thoracic cavity volume. This increased muscular effort is necessary to meet the increased oxygen demand of the body during hyperpnea. Options A and C are incorrect as they incorrectly describe either inspiration or expiration as passive. Option B is incorrect as it inaccurately states that expiration is passive, which is not the case during hyperpnea.

Correct Answer: C

Rationale: The correct answer is C: emphysema. Emphysema is a condition characterized by the destruction of alveolar walls, leading to a decrease in alveolar surface area for gas exchange. This reduction in surface area impairs the exchange of oxygen and carbon dioxide in the lungs. In contrast, lung cancer (A) primarily affects lung tissue but may not directly reduce alveolar surface area. Atelectasis (B) refers to the collapse of lung tissue, which can impact ventilation but not necessarily alveolar surface area. Pneumothorax (D) is the presence of air in the pleural space and does not directly affect alveolar surface area.

Correct Answer: A

Rationale: The correct answer is A: olfactory epithelium. The olfactory epithelium is responsible for detecting smells, not providing chemoreceptor input to the respiratory centers in the medulla oblongata. Medullary chemoreceptors, aortic body, and carotid body are all involved in sensing oxygen, carbon dioxide, and pH levels in the blood, providing crucial input to regulate breathing. The olfactory epithelium is not directly involved in respiratory regulation, making it the exception in this context.

Correct Answer: A

Rationale: 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.