The nurse discovers that an older client with no history of cardiac or renal disease has an elevated serum magnesium level. To further investigate the cause of this electrolyte imbalance, what information is most important for the nurse to obtain from the client's medical history?

The property of the drugs that, if shared by both, indicates a need to closely monitor the client for drug toxicity is:

Highly protein bound.

When a drug is highly protein bound, it means that a significant portion of the drug molecules bind to proteins in the bloodstream. This binding can affect the availability and distribution of the drug in the body. If two drugs are highly protein bound and administered together, they may compete for binding sites on the proteins, leading to increased levels of unbound (free) drug in the bloodstream. This can result in higher drug concentrations and an increased risk of drug toxicity.

Closely monitoring the client for drug toxicity is necessary when drugs are highly protein bound because there is a potential for increased drug levels and associated adverse effects. Monitoring for signs and symptoms of drug toxicity, as well as routine laboratory tests to assess liver and kidney function, may be necessary in these cases.

The other properties listed do not necessarily indicate a need for closer monitoring for drug toxicity:

• Low bioavailability refers to the fraction of an administered dose that reaches the systemic circulation in an active form. While low bioavailability can affect the effectiveness of a drug, it does not directly imply a need for closer monitoring for drug toxicity.
• Short half-life refers to the time it takes for half of the drug concentration in the body to be eliminated. While drugs with short half-lives may require more frequent dosing, this property does not inherently suggest a need for closer monitoring for drug toxicity.
• High therapeutic index indicates a wide margin of safety for a drug, meaning that the effective dose is significantly lower than the toxic dose. A high therapeutic index implies that the drug has a wide safety margin and is less likely to cause drug toxicity.

The client's serum potassium level is elevated at 6.0 mEq/L (6.0 mmol/L), which is above the normal reference range of 3.5 to 5.0 mEq/L (3.5 to 5.0 mmol/L).

Hyperkalemia can have significant cardiac implications, including the potential for life-threatening dysrhythmias. Therefore, close monitoring of the serum potassium level is crucial to assess the effectiveness of interventions and ensure that potassium levels are within a safe range.

While monitoring glucose levels before and after meals is important for clients receiving insulin therapy, in this scenario, the primary concern is the elevated potassium level.

The nurse should prioritize frequent assessment of the serum potassium level to guide appropriate management and prevent complications associated with hyperkalemia.

Monitoring and documenting strict intake and output are important for assessing fluid balance and renal function, but in this case, the elevated potassium level takes precedence as it poses a more immediate risk to the client's well-being.

Obtaining a 12-lead electrocardiogram (ECG) daily may be indicated in some cases of hyperkalemia, as certain ECG changes can be associated with elevated potassium levels. However, the more critical aspect is monitoring the potassium level itself, as ECG changes can occur rapidly and may not always be detectable on a daily basis.