Physical assessment of a client with cardiac dysrhythmia reveals hypoactive bowel sounds, muscle weakness, dizziness, postural hypotension, shallow respirations, increased fatigue, and decreased tendon reflexes

Question

The laboratory result consistent with these findings is a. serum calcium level of 4.3 mEq/L.
b. serum magnesium level of 1.3 mEq/L.
c. serum phosphorus level of 1.1 mEq/L.
d. serum potassium level of 3.0 mEq/L.

Answer 1

D
Hypokalemia will cause slowed smooth and skeletal muscle contraction. Hypokalemia is present when serum potassium level is less than 3.5 mEq/L. Hypocalcemia (option a) would cause manifestations such as a positive Chvostek's sign and positive Trousseau's sign due to neuronal excitability and irritability in the motor and sensory nerves. Hypomagnesemia (option b) can cause myocardial irritability, psychological manifestations, and decreased contractility in the GI tract leading to nausea, anorexia, and abdominal distention. Severe hypomagnesemia can also cause positive Chvostek's and Trousseau's signs. Option c, hypophosphatemia, leads to manifestations that result from impaired ATP production: decreased cardiac and respiratory function, weakness, fatigue, brittle bones, bone pain, confusion, and seizures.