ATI LPN
Questions for the Respiratory System Questions
Question 1 of 5
The nurse is caring for a client diagnosed with Pneumocystis jiroveci. Which intervention should the nurse include in the plan of care to help decrease the client's metabolic demands?
Correct Answer: B
Rationale: Frequent, small meals (B) decrease metabolic demand in Pneumocystis jiroveci pneumonia small portions (e.g., 200 kcal) reduce Oâ‚‚ use versus large meals (500 kcal). Active ROM (A) increases demand. Family support (C) aids stress, not metabolism directly. Splinting (D) eases cough, not demand. The implied answer (B) aligns P. jiroveci's hypoxia (PaOâ‚‚ <70 mmHg) taxes reserves, and B conserves energy, distinguishing it from A's exertion.
Question 2 of 5
Which of the following terms identifies the anatomical region found between the lungs that extends from the sternum to the vertebral column and from the first rib to the diaphragm?
Correct Answer: D
Rationale: The mediastinum is the anatomical region between the lungs, stretching from the sternum to the vertebral column and first rib to diaphragm, containing the heart, trachea, esophagus, and major vessels. The epicardium is the heart's outer layer, not a region. The abdominal cavity lies below the diaphragm, unrelated. The pericardium encases the heart within the mediastinum, not the broader space. This central compartment's role in housing vital structures makes it a critical anatomical landmark, key in thoracic surgery and understanding mediastinal pathology like tumors or infections.
Question 3 of 5
Blood leaving the left ventricle passes through which of the following structures?
Correct Answer: D
Rationale: Blood exits the left ventricle through the aortic semilunar valve, opening during systole to release oxygenated blood into the aorta, closing to prevent backflow. The right atrium receives deoxygenated blood, unrelated. The interventricular septum divides ventricles, not a passage. The bicuspid (mitral) valve admits blood into the ventricle, not out. This valve's half-moon shape optimizes ejection, a critical step in systemic circulation, essential in understanding cardiac output and conditions like aortic stenosis narrowing this exit.
Question 4 of 5
In comparison to skeletal muscle fibers, the contractile fibers of the heart are depolarized for _____ period of time.
Correct Answer: B
Rationale: Cardiac muscle fibers depolarize longer than skeletal muscle due to a prolonged plateau phase in their action potential, driven by calcium influx through L-type channels, lasting ~200-300 ms versus skeletal's ~2-5 ms. This extended depolarization ensures sustained contraction, preventing tetanus and allowing complete ventricular ejection per beat. Skeletal muscle's brief depolarization suits rapid, repeated motions. 'Same' ignores this distinction; cardiac's unique refractory period matches its continuous duty. This longer phase, key to heart rhythm, is critical in ECG interpretation and antiarrhythmic drug effects targeting calcium channels.
Question 5 of 5
Cardiac output is the volume of blood ejected from the _____ ventricle into the _____ each minute.
Correct Answer: C
Rationale: Cardiac output (CO) is the blood volume ejected from either ventricle left into the aorta (systemic), right into the pulmonary trunk (lungs) per minute, ~5 L total. 'Left, aorta' or 'right, pulmonary' alone is half; 'right, aorta' is wrong. This dual definition reflects parallel circuits, key in measuring heart efficiency, critical in failure where CO drops, a broad metric in physiology.