Final answer:
The correct nursing measures when administering intravenous aminoglycosides after gastrointestinal surgery are to monitor serum creatinine levels and instruct the patient to report any dizziness or feeling of fullness in the ears.
Step-by-step explanation:
When administering an intravenous aminoglycoside to a patient who has had gastrointestinal surgery, the nursing measures that are appropriate include monitoring serum creatinine levels to assess kidney function, as aminoglycosides can cause nephrotoxicity. Additionally, instructing the patient to report any dizziness or a feeling of fullness in the ears is essential since these drugs can have ototoxic effects. However, reporting a trough drug level of 0.8 mcg/mL does not automatically warrant holding the drug without a physician's directive, as this level may be within the therapeutic range for some aminoglycosides. Enforcing strict fluid restriction is not typically associated with aminoglycoside therapy, and should be based on the patient's condition and physician advice. Warning the patient about urine color changes is also not a standard precaution with aminoglycosides, as they do not commonly cause significant changes in urine color. Therefore, c. Monitor serum creatinine levels and d. Instruct the patient to report dizziness or a feeling of fullness in the ears are the correct nursing measures to select.