Which of the following neurological controls of ventilation responds to changes in the pH and levels of oxygen and CO2 in the blood?
- A. Central chemoreceptors in the medulla
- B. Peripheral chemoreceptors in the aortic arch and carotid arteries
- C. Respiratory centers in the medulla oblongata and pons
- D. Central chemoreceptors in the spinal cord
Correct Answer: A
Rationale: The correct answer is A. Central chemoreceptors in the medulla are highly sensitive to changes in pH and CO2 levels, influencing respiratory rate and depth. B is incorrect because peripheral chemoreceptors respond mainly to O2 levels. C refers to general respiratory control centers, not specific chemoreceptor function. D is incorrect as the spinal cord lacks central chemoreceptors.
You may also like to solve these questions
The partial pressure of oxygen in atmospheric air at sea level is
- A. greater than the partial pressure of oxygen in atmospheric air at the top of Mt. Everest
- B. less than the partial pressure of oxygen in atmospheric air at the top of Mt. Everest
- C. equal to the partial pressure of oxygen in atmospheric air at the top of Mt. Everest
- D. equal to the sum of partial pressures from carbon dioxide and nitrogen
Correct Answer: A
Rationale: The correct answer is A because the partial pressure of oxygen decreases with increasing altitude due to the decrease in atmospheric pressure. At sea level, the atmospheric pressure is higher, resulting in a higher partial pressure of oxygen compared to the top of Mt. Everest. Choice B is incorrect because the partial pressure of oxygen is not higher at higher altitudes. Choice C is incorrect because the partial pressure of oxygen is not equal at sea level and Mt. Everest. Choice D is incorrect because the question specifically asks about the partial pressure of oxygen only, not the sum of partial pressures from other gases.
The ED nurse is assessing a patient complaining of dyspnea. The nurse auscultates the patient's chest and hears wheezing throughout the lung fields. What might this indicate?
- A. The patient has a narrowed airway.
- B. The patient has pneumonia.
- C. The patient needs physiotherapy.
- D. The patient has a hemothorax.
Correct Answer: A
Rationale: The correct answer is A: The patient has a narrowed airway. Wheezing throughout the lung fields indicates the presence of narrowed airways, often due to conditions like asthma or chronic obstructive pulmonary disease (COPD). Wheezing is caused by turbulent airflow through narrowed airways, leading to a high-pitched whistling sound during expiration. This is a characteristic finding in patients with obstructive airway diseases.
Summary of other choices:
B: The patient having pneumonia would typically present with symptoms like fever, cough, and consolidation on auscultation, not wheezing.
C: The patient needing physiotherapy may have respiratory muscle weakness or secretion clearance issues but would not typically present with wheezing throughout lung fields.
D: The presence of a hemothorax (blood in the pleural space) would manifest as decreased breath sounds and signs of respiratory distress but not wheezing.
Before administering ephedrine, Nurse Tony assesses the patient's history. Because of ephedrine's central nervous system (CNS) effects, it is not recommended for:
- A. Patients with an acute asthma attack.
- B. Patients with narcolepsy.
- C. Patients under age
- D. Elderly patients.
Correct Answer: D
Rationale: The correct answer is D: Elderly patients. Ephedrine, a sympathomimetic amine, can exacerbate existing CNS conditions in elderly patients, leading to adverse effects like confusion, agitation, and increased risk of falls. Elderly patients are more sensitive to CNS stimulants due to age-related changes in drug metabolism and clearance, making them more susceptible to negative effects. Choices A, B, and C are incorrect because patients with acute asthma attacks may benefit from ephedrine's bronchodilator effects, patients with narcolepsy may benefit from its stimulant properties, and age alone is not a contraindication for ephedrine use.
Which statement made by a client with coronary artery disease after the nurse has completed teaching about the therapeutic lifestyle changes (TLC) diet indicates that further teaching is needed?
- A. I enjoy eating 1/4 cup of walnuts every day.
- B. I will switch from whole milk to skim milk.
- C. I can have a glass of wine with dinner every night.
- D. I like red meat and I will plan to eat it more often.
Correct Answer: D
Rationale: The correct answer is D because red meat is high in saturated fat which can worsen coronary artery disease. Eating it more often contradicts the TLC diet's aim to reduce saturated fat intake. Choice A is correct as walnuts are heart-healthy. Choice B is correct as switching to skim milk reduces saturated fat. Choice C is incorrect as alcohol should be consumed in moderation, not daily.
A nurse instructs a female client to use the pursed-lip method of breathing and the client asks the nurse about the purpose of this type of breathing. The nurse responds, knowing that the primary purpose of pursed-lip breathing is to:
- A. Promote oxygen intake.
- B. Strengthen the diaphragm.
- C. Strengthen the intercostal muscles.
- D. Promote carbon dioxide elimination.
Correct Answer: D
Rationale: The correct answer is D: Promote carbon dioxide elimination. Pursed-lip breathing is a technique used to slow down breathing and help control shortness of breath. By exhaling through pursed lips, it creates back-pressure in the airways, allowing more time for the lungs to empty and facilitating better removal of carbon dioxide. This helps improve oxygenation by optimizing the gas exchange process. Choices A, B, and C are incorrect because pursed-lip breathing primarily focuses on improving ventilation and gas exchange, not specifically on increasing oxygen intake or strengthening specific respiratory muscles.