Final answer:
The nurse anticipates that diagnostic tests for a patient with dark tarry stools and occasional blood on the toilet paper would include (A) upper gastrointestinal endoscopy, (B) stool guaiac test, (C) CBC, and (D) colonoscopy to diagnose potential causes of gastrointestinal bleeding.
Step-by-step explanation:
A patient reporting a 2-month history of dark tarry stools, occasional blood on toilet paper, generalized weakness, and fatigue, who denies a history of taking iron pills or consuming foods that could discolor stool, is likely experiencing clinical signs of gastrointestinal bleeding.
Diagnostic tests that the nurse anticipates will be prescribed to determine the cause of the blood include: A. Upper gastrointestinal endoscopy, which is used to visualize and diagnose upper GI tract issues; B. Stool guaiac test to detect the presence of occult blood in the stool; C. Complete blood count (CBC) to assess for anemia that can result from chronic blood loss; and D. Colonoscopy for direct visualization of the colon and rectum to identify potential sources of bleeding, such as colorectal cancer or polyps.
Patients with bloody stools might need all these diagnostic tests to ensure a thorough evaluation, especially considering the risk of colorectal polyps or cancer.