Final answer:
The most critical lab values for a nurse to monitor in a client with Tetany are ionized calcium and serum phosphate levels, as these are directly related to the condition.
Step-by-step explanation:
The nurse caring for a client admitted with Tetany should primarily monitor the client's ionized calcium levels. Tetany is often caused by a decrease in ionized calcium in the serum which can result from various conditions such as an increase in blood pH, poor calcium absorption, decreased dietary intake, or increased renal excretion. Therefore, checking the serum phosphate levels is also important since a reciprocal relationship exists between the concentrations of calcium and phosphate ions in plasma, and a significant increase in serum phosphate can lead to a fall in serum calcium concentration.
While total protein and blood glucose levels might also be relevant to the patient's overall health, they are not directly related to Tetany which is primarily associated with calcium and phosphate levels. Nevertheless, in the assessment of hypocalcemia, blood glucose estimation might be necessary because insulin release can be impaired in the absence of calcium, potentially leading to hyperglycemia.