Final answer:
The most important additional information a nurse should consider when reviewing a patient's total calcium level is if the serum albumin level is low, because it can affect the interpretation of calcium levels.
Step-by-step explanation:
When reviewing the laboratory results for a patient's total calcium level, the additional information a nurse needs to consider that is pertinent is c. The serum albumin level is low. Calcium in the blood exists in two forms: bound to proteins like albumin and in a free, ionized form which is biologically active. When serum albumin is low, total calcium may appear lower than its physiological active form. Since about 40% of calcium is bound to albumin, hypoalbuminemia can lead to hypocalcemia, or abnormally low blood levels of calcium. However, it is the ionized calcium level that is clinically significant, so adjustments based on albumin levels may be necessary to accurately interpret total calcium levels.
Other factors, such as hyperphosphatemia, indicated by increased serum phosphate levels, can also impact calcium levels by causing a reciprocal decrease in serum calcium. Additionally, factors like parathyroid hormone play a critical role in calcium regulation.