When planning care for a client who is diagnosed with a large abdominal aortic aneurysm (AAA), the nurse should carefully monitor for which signs and symptoms?

A) Flank pain and profound hypotension:

Correct. Flank pain, often described as a deep, constant, gnawing, or throbbing sensation in the abdomen or back, can be a sign of impending rupture or dissection of an abdominal aortic aneurysm (AAA). Profound hypotension may occur if the AAA ruptures, leading to massive internal bleeding and shock. Prompt recognition of these signs is crucial for early intervention and surgical repair to prevent catastrophic consequences.

B) Acute shortness of breath and chest pain:

Acute shortness of breath and chest pain are more indicative of cardiovascular or pulmonary conditions such as myocardial infarction, pulmonary embolism, or acute coronary syndrome rather than an abdominal aortic aneurysm. While aortic dissection can present with chest pain, it is typically described as severe, tearing, or ripping pain that radiates to the back, not as acute shortness of breath.

C) Absent pedal pulses and darkened toes:

Absent pedal pulses and darkened toes may indicate peripheral vascular disease or critical limb ischemia but are not specific signs of an abdominal aortic aneurysm. While AAA can lead to peripheral ischemia in advanced cases, it is not typically associated with acute changes in pedal pulses or toe discoloration.

D) Tea-colored urine and decreased output:

Tea-colored urine and decreased urine output may indicate acute kidney injury or rhabdomyolysis but are not specific signs of an abdominal aortic aneurysm. While a ruptured AAA can lead to renal ischemia and acute kidney injury due to hypoperfusion, these symptoms are not the primary manifestations of AAA

The loop of Henle, a critical structure within the nephron of the kidney, plays a key role in the concentration of urine through the process of countercurrent multiplication. Here's why option D is the correct choice:

A) Calyx:

The calyx is a structure in the kidney that collects urine from the renal papillae and channels it into the renal pelvis. It does not directly participate in the concentration of urine.

B) Proximal convoluted tubule:

The proximal convoluted tubule primarily reabsorbs water, electrolytes, and nutrients from the glomerular filtrate, but it does not contribute significantly to the concentration of urine.

C) Renal pelvis:

The renal pelvis is a funnel-shaped structure that collects urine from the calyces and funnels it into the ureter. It is not directly involved in the concentration of urine.

D) The loop of Henle:

Correct. The loop of Henle is the nephron segment responsible for generating a hypertonic medullary interstitium, which creates the osmotic gradient necessary for urine concentration. The loop of Henle achieves this through countercurrent multiplication, where the descending limb allows passive reabsorption of water, while the ascending limb actively pumps out sodium and chloride ions. This creates an osmotic gradient that allows for further water reabsorption in the collecting ducts, leading to concentrated urine.