The nurse recognizes that urinary elimination changes may occur even in healthy older adults because of which of the following?
A. The bladder distends and its capacity increases.
B. Older adults ignore the need to void.
C. Urine becomes more concentrated.
D. The amount of urine retained after voiding increases.
Correct Answer: D. The amount of urine retained after voiding increases
The capacity of the bladder may decrease with age but the muscle is weaker and can cause urine to be retained. Muscle changes and changes in the reproductive system can affect bladder control. As the volume of urine held by the bladder increases, so too does the pressure therein. Wall pressure of 5 to 15 mm Hg creates a sensation of bladder fullness while 30 mm Hg and beyond is painful. The sensation of increasing bladder fullness is conveyed to the spinal cord via the pudendal and hypogastric nerves on both A-delta and C nerve fibers.
Option A: The bladder wall changes. The elastic tissue becomes tough and the bladder becomes less stretchy. The bladder cannot hold as much urine as before. The urethra can become blocked. In women, this can be due to weakened muscles that cause the bladder or vagina to fall out of position (prolapse). In men, the urethra can become blocked by an enlarged prostate gland.
Option B: Older adults don’t ignore the urge to void and may have difficulty getting to the toilet in time. Bladder capacity changes throughout one’s life. In children, an approximation of bladder volume can be calculated with the formula: (years of age + 2) x 30 mL. By adulthood, the average volume that a functional bladder can comfortably hold is between 300 and 400 mL.
Option C: The kidney becomes less able to concentrate urine with age. Urination or micturition primarily functions in the excretion of metabolic products and toxic wastes. The urinary tract also serves as a storage vessel of the waste filtered from the kidneys. Urine stored in the bladder is released from the bladder through the urethra upon a complex network of neurological function.