A patient has been admitted to the postsurgical nursing unit after surgery. The health care provider has ordered the patient to have an IV of 0.9 sodium chloride. The nurse who is caring for the patient recognizes this as what type of solution?

B. One of the significant changes that occur with aging is a decline in kidney function. This includes a decrease in renal blood flow, glomerular filtration rate (GFR), and the ability of the kidneys to concentrate urine. These changes can impair the body's ability to conserve water and maintain electrolyte balance, increasing the risk of dehydration.

A. As individuals age, there is actually a decrease in the percentage of body water relative to lean body mass. This is because aging is associated with an increase in adipose tissue and a decrease in muscle mass, which affects the overall body composition.

C Saliva production typically decreases with age, rather than increases. Reduced saliva production can contribute to dry mouth and may affect hydration status indirectly, but it is not a primary factor in increasing dehydration risk in older adults.

D. While changes in blood pressure can occur with aging, such as an increase in systolic blood pressure due to arterial stiffening, this does not directly contribute to an increased risk of dehydration. Blood pressure changes are more related to cardiovascular health rather than fluid balance.

To calculate the flow rate in gtt/min, the total volume (400 mL) should be divided by the total time in minutes (8 hours x 60 minutes/hour = 480 minutes). This gives the mL/min.

Then, multiply the mL/min by the drop factor (60 gtt/mL) to get the gtt/min. So, the calculation would be (400 mL / 480 min) x 60 gtt/mL = 50 gtt/min.

Therefore, the nurse should set the manual IV infusion to deliver 50 gtt/min.