Nursing Elites

1. When educating a client about to undergo a pacemaker insertion, the nurse explains the normal phases of cardiac muscle tissue. During the repolarization phase, the nurse will stress that membranes must be repolarized before they can be re-excited. Within the cell, the nurse understands that:

• A. Potassium channels open while sodium channels close, causing repolarization to the resting state.
• B. The influx of calcium is the primary stimulus for the repolarization of cardiac tissue.
• C. Only the electrical activity within the heart will determine when repolarization occurs.
• D. The cell membranes need to stay calm, resulting in muscle tissue becoming refractory.

Correct answer: A

Rationale: During the repolarization phase of cardiac muscle tissue, potassium channels open while sodium channels close. This process is crucial for the cardiac muscle to return to its resting state after depolarization. Potassium moving out of the cell and sodium staying out helps reset the membrane potential and prepare the cell for the next depolarization phase. The influx of calcium is not the primary stimulus for repolarization in cardiac tissue; it is mainly involved in the depolarization phase. While electrical activity within the heart influences repolarization, the specific ion movements described in choice A are what physiologically drive repolarization. Cell membranes need to be in an active state during repolarization, not calm, to facilitate the necessary ion movements for muscle tissue to properly function.

2. Following a spinal cord injury suffered in a motor vehicle accident, a 22-year-old male has lost fine motor function of his finger and thumb, but is still able to perform gross motor movements of his hand and arm. Which component of his 'white matter' has most likely been damaged?

• A. The inner layer (archilayer)
• B. The middle layer (paleolayer)
• C. The outer layer (neolayer)
• D. The reticular formation

Correct answer: C

Rationale: The correct answer is C: The outer layer (neolayer). The white matter of the spinal cord consists of three layers: the outer layer (neolayer), the middle layer (paleolayer), and the inner layer (archilayer). Damage to the outer layer (neolayer) is likely to affect fine motor skills, explaining the loss of fine motor function in the finger and thumb while gross motor movements remain intact. Choices A, B, and D are incorrect as they do not correspond to the specific layer of the white matter that is typically associated with fine motor control.

3. Rhabdomyolysis can result in serious complications. In addition to muscle pain and weakness, a patient will complain of:

• A. paresthesias.
• B. bone pain.
• C. dark urine.
• D. diarrhea.

Correct answer: C

Rationale: Dark urine is a classic symptom of rhabdomyolysis. When muscle breakdown occurs, myoglobin is released into the bloodstream and filtered by the kidneys, leading to dark urine. Paresthesias (choice A) refer to abnormal sensations like tingling or numbness and are not typically associated with rhabdomyolysis. Bone pain (choice B) is not a prominent symptom of rhabdomyolysis. Diarrhea (choice D) is not a common complaint in rhabdomyolysis cases and is not directly related to muscle breakdown.

4. Which of the following is a clinical manifestation in a patient with renal impairment associated with polycystic kidney disease?

• A. Suprapubic pain
• B. Periorbital edema
• C. Low serum creatinine level
• D. Palpable kidneys

Correct answer: D

Rationale: The correct answer is D: Palpable kidneys. Polycystic kidney disease often leads to the development of multiple fluid-filled cysts within the kidneys, causing them to enlarge. Enlarged kidneys can be palpated during a physical examination. Choices A, B, and C are incorrect. Suprapubic pain is not a typical clinical manifestation of polycystic kidney disease. Periorbital edema is more commonly associated with conditions like nephrotic syndrome or heart failure. Low serum creatinine level is not expected in patients with renal impairment due to polycystic kidney disease; instead, elevated serum creatinine levels are more likely.

5. A patient is prescribed tadalafil (Cialis) for erectile dysfunction. What condition would contraindicate the use of this medication?

• A. History of hypertension
• B. Use of nitrates
• C. Use of antihypertensive medications
• D. History of peptic ulcer disease

Correct answer: B

Rationale: The correct answer is B: 'Use of nitrates.' Tadalafil (Cialis) is contraindicated in patients using nitrates due to the risk of severe hypotension. Nitrates and tadalafil both cause vasodilation, leading to a synergistic effect that can result in a dangerous drop in blood pressure. Choices A, C, and D are incorrect because a history of hypertension, the use of antihypertensive medications, and a history of peptic ulcer disease are not direct contraindications for tadalafil use.

Similar Questions