A nurse is caring for a client who is receiving oxygen at 2 L/min via a nasal cannula. The nurse recognizes the client is receiving which of the following inspired oxygen concentration?

A) An older adult who is confused and has urinary frequency:
This client is at the greatest risk for a fall due to several factors. Confusion increases the likelihood of disorientation and impaired judgment, leading to accidents. Urinary frequency may necessitate frequent trips to the bathroom, increasing the chances of falls, especially if the client is disoriented or unsteady on their feet.

B) An older adult with hearing impairment:
While hearing impairment can contribute to a fall risk by limiting the client's ability to hear warnings or instructions, it may not pose as immediate a risk as confusion and urinary frequency, which directly affect mobility and judgment.

C) A client who has a dressing on his foot due to a pressure ulcer:
While having a dressing on the foot due to a pressure ulcer increases the risk of falls by potentially affecting the client's gait and balance, it may not be as significant a risk factor as confusion and urinary frequency, which directly impact the client's ability to safely navigate their environment.

D) A client who has osteoarthritis and uses a walker:
Although osteoarthritis and the use of a walker can contribute to mobility issues and an increased risk of falls, they may not present as immediate a risk as confusion and urinary frequency, which can lead to more unpredictable and hazardous situations.

A) Lactated Ringer's:
Lactated Ringer's solution is an isotonic crystalloid solution that contains electrolytes similar to those found in plasma. It is commonly used for fluid resuscitation and maintenance therapy but is not typically used for treating hypernatremia, as it contains sodium chloride and could exacerbate the client's condition.

B) Dextrose 10% in water:
Dextrose 10% in water is a hypertonic solution primarily used to provide calories and treat hypoglycemia. It does not address the underlying electrolyte imbalance in hypernatremia.

C) 0.45% sodium chloride:
0.45% sodium chloride, also known as half-normal saline, is a hypotonic solution used to treat hypernatremia by diluting the excess sodium in the bloodstream. It provides free water to rehydrate cells without adding excessive sodium. This solution is appropriate for clients with hypernatremia who require IV fluid therapy.

D) Dextrose 5% in 0.9% sodium chloride:
Dextrose 5% in 0.9% sodium chloride, also known as D5NS, is a hypertonic solution containing both dextrose and sodium chloride. While it provides water and calories, the sodium content may exacerbate hypernatremia rather than correct it. Therefore, it is not the most appropriate choice for a client with hypernatremia.