ATI RN
Foundations and Adult Health Nursing Study Guide Answers Questions
Question 1 of 5
Which of the following mechanisms is responsible for the generation of diversity in the antigen-binding sites of immunoglobulins?
Correct Answer: A
Rationale: Somatic hypermutation is the mechanism responsible for generating diversity in the antigen-binding sites of immunoglobulins. During somatic hypermutation, point mutations are introduced into the variable regions of immunoglobulin genes in B cells. These mutations occur randomly and lead to a wide range of amino acid changes in the antigen-binding sites of antibodies. As a result, a diverse repertoire of antibodies with varying specificities for different antigens is created. Gene rearrangement and isotype switching are other mechanisms that contribute to antibody diversity but do not specifically target the antigen-binding sites. Clonal expansion, on the other hand, refers to the proliferation of specific B cell clones after activation by antigens, which amplifies the immune response but does not directly impact the diversity of antigen-binding sites.
Question 2 of 5
A patient with obstructive sleep apnea (OSA) presents with excessive daytime sleepiness, loud snoring, and witnessed apneic episodes during sleep. Which of the following interventions is most appropriate for managing OSA and improving symptoms?
Correct Answer: B
Rationale: CPAP therapy is considered the gold standard treatment for obstructive sleep apnea (OSA) and is the most appropriate intervention for managing OSA and improving symptoms. CPAP therapy involves using a machine that delivers a continuous flow of air through a mask worn over the nose or mouth during sleep. This air pressure helps keep the airway open, preventing the collapse that causes apneas and snoring during sleep.
Question 3 of 5
A patient with chronic obstructive pulmonary disease (COPD) is admitted to the hospital with acute exacerbation and respiratory failure requiring mechanical ventilation. Which of the following ventilator settings is most appropriate for minimizing the risk of ventilator-induced lung injury (VILI) in this patient?
Correct Answer: A
Rationale: Patients with COPD are at increased risk for developing ventilator-induced lung injury (VILI) due to their underlying lung pathology. Using a low tidal volume strategy (6-8 ml/kg predicted body weight) has been shown to reduce the risk of VILI in these patients. Additionally, applying high positive end-expiratory pressure (PEEP) helps to recruit collapsed alveoli, improve oxygenation, and decrease the risk of barotrauma by keeping the alveoli open throughout the respiratory cycle. Therefore, the most appropriate ventilator settings to minimize the risk of VILI in a COPD patient with acute exacerbation and respiratory failure requiring mechanical ventilation would be low tidal volume and high PEEP.
Question 4 of 5
A patient presents with bone pain, fatigue, and frequent infections. Laboratory tests reveal pancytopenia, hypocellular bone marrow, and absence of reticulocytes. Which of the following conditions is most likely to cause these findings?
Correct Answer: A
Rationale: Aplastic anemia is a condition characterized by a reduction in the number of all three blood cell types: red blood cells, white blood cells, and platelets. The patient's presentation of bone pain, fatigue, frequent infections, pancytopenia (decreased counts of all blood cell types), hypocellular bone marrow (reduced cellularity in the bone marrow), and absence of reticulocytes is indicative of aplastic anemia.
Question 5 of 5
A patient with a history of sickle cell disease presents with severe abdominal pain, fever, and jaundice. Laboratory tests reveal anemia, reticulocytosis, elevated indirect bilirubin, and presence of Howell-Jolly bodies on peripheral blood smear. Which of the following conditions is most likely to cause these findings?
Correct Answer: A
Rationale: Acute splenic sequestration crisis is a complication seen in patients with sickle cell disease characterized by the sudden pooling of sickled red blood cells in the spleen, leading to splenic enlargement, severe anemia, and hypovolemic shock. This pooling results in a rapid drop in hemoglobin levels, causing anemia. The spleen's sequestration of large numbers of red blood cells can cause a sudden rise in the number of immature red blood cells (reticulocytes) in the blood (reticulocytosis). The destruction of these trapped red blood cells in the spleen leads to hemolysis, evidenced by elevated indirect bilirubin levels and the presence of Howell-Jolly bodies (nuclear remnants of erythrocytes) on peripheral blood smear. Patients may present with severe abdominal pain, fever, jaundice, and signs of hemodynamic instability, which