A client with a history of heart failure arrives at the emergency department describing an onset of fatigue and weakness.

The client has been taking spironolactone 50 mg tablets PO every day.

The nurse receives a report from the lab that the client has a serum potassium level of 6.2 mEq/L (6.2 mmol/L). Which intervention is most important for the nurse to implement?

Choice A rationale
A potassium level of 4.4 mEq/L (4.4 mmol/L) is within the normal range. Potassium is a critical electrolyte in the body, playing key roles in cellular metabolism, protein synthesis, and electrical action potential regulation across cell membranes. Normal potassium levels typically range from 3.5 to 5.1 mmol/L1. Therefore, a potassium level of 4.4 mEq/L indicates that the patient’s potassium level is within the normal range, which is a safe condition for the administration of vancomycin.
Choice B rationale

The use of antibiotics for prophylaxis, or prevention, is a common practice in healthcare, particularly in surgical procedures such as pacemaker insertion. This is done to prevent potential infections that could occur during or after the procedure. Vancomycin is a type of antibiotic that is often used for prophylaxis against infections caused by gram-positive bacteria, including methicillin-resistant Staphylococcus aureus (MRSA)3. Therefore, if the antibiotic is being used for prophylaxis, it would be safe to administer vancomycin.
Choice C rationale
A blood urea nitrogen (BUN) level of 17 mg/dL (6.07 mmol/L) is within the normal range. The BUN test measures the amount of urea nitrogen in the blood, which can provide important information about kidney function. Urea nitrogen is a waste product that is created in the liver when protein is metabolized. It is then transported through the blood to the kidneys, which filter out most of the urea nitrogen, leaving a small amount in the blood. Normal BUN levels typically range from 6 to 20 mg/dL4. Therefore, a BUN level of 17 mg/dL indicates that the patient’s kidney function is within the normal range, which is a safe condition for the administration of vancomycin.
Choice E rationale
The absence of known allergies in a patient is a crucial factor in determining the safety of administering any medication, including vancomycin. Allergic reactions to medications can range from mild symptoms such as rash and itching to severe and life-threatening conditions such as anaphylaxis. Therefore, if a patient has no known allergies, it would be safe to administer vancomycin.
Choice D rationale

While it’s true that the dosage of the antibiotic should be within the safe range, the specific dosage of vancomycin for the patient isn’t provided in the question. Therefore, we cannot definitively say that this condition is met based on the information given.
Choice F rationale
Although vancomycin can be administered via a peripheral IV in a large vein, it’s important to note that vancomycin has a low pH and may cause venous irritation and tissue damage in cases of extravasation. Therefore, while it’s possible to administer vancomycin this way, it’s not necessarily an indicator of safety.

Management of respiratory distress in a long-term smoker requires knowledge of oxygen delivery systems and airway humidification. The nurse must apply principles of respiratory therapy to select equipment that ensures precise flow regulation and moisture addition to prevent mucosal drying during supplemental oxygen administration.

Choice A rationale: Lamb’s wool is occasionally used to protect skin from pressure sores caused by medical tubing. However, it is not a standard or essential component for initiating oxygen therapy, as modern medical-grade foam dressings or specialized tubing protectors are more commonly utilized in clinical practice.

Choice B rationale: Sterile water is essential for the humidification process when oxygen flow rates exceed 4 liters per minute. It serves as the reservoir liquid in the humidifier bottle to ensure the inhaled gas is moist, preventing the drying of sensitive respiratory mucosa and secretions.

Choice C rationale: Tape is generally avoided when securing nasal cannulas because it can cause skin irritation or breakdown on the face. The cannula is designed to be secured using the integrated sliding bolo or by looping the flexible tubing comfortably behind the patient's ears.

Choice D rationale: A suction canister is used for removing secretions from the oropharynx or trachea. While it may be present at the bedside for safety, it is not a functional component of the oxygen delivery system itself, which focuses on gas inhalation rather than extraction.

Choice E rationale: A humidifier bottle is necessary to add water vapor to the dry oxygen gas provided by the wall source. Humidification is vital for patient comfort and to maintain the integrity of the mucociliary escalator, especially for patients with chronic lung irritation from smoking.

Choice F rationale: The nasal cannula is the primary interface for delivering low-to-medium concentrations of oxygen. It consists of two prongs that fit into the nares, allowing the patient to breathe supplemental oxygen while still being able to speak and consume fluids or meals.

Choice G rationale: A flowmeter is a critical device that attaches to the oxygen wall outlet to regulate the liters per minute delivered. It allows the nurse to accurately titrate the oxygen dose according to the healthcare provider's specific orders and the patient's oxygenation needs.