A nurse is caring for a client in a cardiac telemetry unit and notes the image above on the client's EKG strip. Which electrolyte value should the nurse be concerned about?

Correct Answer: A

Rationale: The EKG shows inverted T-waves, a hallmark of hypokalemia (low potassium, A), which affects repolarization. Calcium (B) impacts rate/contractility, not T-waves, and chloride (C) and sodium (D) abnormalities don’t typically cause this pattern. (Source: Document, p. 10-11; assumes image context)

Correct Answer: B

Rationale: The first heart sound (S₁, ‘lub’) occurs when AV valves (tricuspid, mitral) close at the start of ventricular systole (B). Semilunar valve closure (A) is S₂ (‘dub’), and atrial contraction (C) precedes S₁, not causing it.

Correct Answer: C

Rationale: Fibrillation (C) is rapid, uncoordinated beating (e.g., atrial or ventricular). Heart block (A) is conduction failure, tachycardia (B) is fast but coordinated, and bradycardia (D) is slow.

Correct Answer: B

Rationale: Blood flows from the left ventricle through: artery (aorta), arteriole, capillary, venule, vein (B). A reverses artery-arteriole, C misorders, D starts with veins.

Correct Answer: B

Rationale: Blood flows fastest in arteries (B, ~300-500 mm/s) due to high pressure and large diameter. Capillaries (C, ~0.3 mm/s), venules (A), and arterioles (D) are slower due to smaller size or lower pressure.