A nurse is preparing to administer 4,000 units of heparin subcutaneously to a client who has deep-vein thrombosis. Available in heparin 10,000 units/mL. How many mL of heparin should the nurse administer?
(Round the answer to the nearest tenth. Use a leading zero if it applies. Do not use a trailing zero.)

A. Hypomagnesemia:
Correct Answer: This electrolyte imbalance is the one the nurse should assess the client for.
Explanation: Lithium is primarily excreted by the kidneys, and its excretion can be influenced by factors that affect renal function, including electrolyte imbalances. Hypomagnesemia (low magnesium levels) can potentially reduce the excretion of lithium, leading to increased lithium levels in the blood. This can increase the risk of lithium toxicity, which can be dangerous. Therefore, monitoring magnesium levels is important in clients taking lithium.
B. Hyponatremia:
Incorrect Explanation: While hyponatremia (low sodium levels) is a potential concern, it is not as directly linked to lithium interaction as hypomagnesemia.
Explanation: Lithium can cause diabetes insipidus, which leads to excessive urination and subsequent loss of water and electrolytes, including sodium. However, hyponatremia is not the immediate electrolyte imbalance that arises due to the interaction with lithium.
C. Hypocalcemia:
Incorrect Explanation: Hypocalcemia (low calcium levels) is not a primary concern in the context of lithium use.
Explanation: Lithium does not have a direct interaction with calcium levels. Hypocalcemia is typically not a result of lithium use or its interaction with other factors.
D. Hypokalemia:
Incorrect Explanation: While electrolyte imbalances like hypokalemia (low potassium levels) can have health implications, it is not the primary electrolyte imbalance to be concerned about with lithium use.
Explanation: Hypokalemia is not a direct consequence of lithium interaction. Monitoring potassium levels is important for overall health, but it's not the primary electrolyte imbalance associated with lithium use and its potential interactions.

A. Bradycardia:
Incorrect Explanation: Bradycardia (slow heart rate) is not a common adverse effect of phenytoin.
Explanation: Phenytoin primarily affects the central nervous system and is not known to cause significant cardiovascular effects like bradycardia.
B. Red man syndrome:
Incorrect Explanation: Red man syndrome is associated with some antibiotics, not phenytoin.
Explanation: Red man syndrome, characterized by redness and flushing of the skin, is primarily associated with certain antibiotics like vancomycin and is not a recognized adverse effect of phenytoin.
C. Hypoglycemia:
Incorrect Explanation: Hypoglycemia is not a common adverse effect of phenytoin.
Explanation: Phenytoin does not have a direct impact on blood glucose levels, so hypoglycemia is not a typical adverse effect.
D. Hypotension:
Correct Answer: Hypotension (low blood pressure) is an adverse effect that the nurse should identify as a potential concern with phenytoin administration.
Explanation: Phenytoin, especially when administered rapidly as an IV bolus, can lead to hypotension as one of its adverse effects. Monitoring blood pressure during and after administration is important.