CCRN - Review Hematology and Immunology Questions and Answers

Question 1

A patient with severe sepsis begins bleeding from venipuncture sites and around their central line. Laboratory results show a platelet count of 45,000/mm³, prolonged PT and aPTT, a fibrinogen level of 80 mg/dL, and an elevated D-dimer. These findings are most indicative of which hematologic complication?

Accepted Answer

Disseminated Intravascular Coagulation (DIC)

Answer

Disseminated Intravascular Coagulation (DIC) is a complex syndrome characterized by widespread systemic activation of coagulation, leading to the formation of microthrombi and consumption of clotting factors and platelets. This consumptive coagulopathy results in the paradoxical combination of thrombosis and hemorrhage. The lab profile presented—thrombocytopenia, prolonged clotting times, low fibrinogen, and elevated D-dimer (a fibrin degradation product)—is the classic presentation of DIC, especially in the context of sepsis.

Question 2

A patient has been receiving a continuous heparin infusion for five days for a pulmonary embolism. The nurse notes that the patient's platelet count has dropped from 210,000/mm³ on admission to 90,000/mm³. The nurse suspects Heparin-Induced Thrombocytopenia (HIT). What is the priority nursing intervention?

Accepted Answer

Immediately stop the heparin infusion and notify the healthcare provider.

Answer

The priority intervention for suspected HIT is to immediately discontinue all sources of heparin, including the infusion and any heparin-containing flushes. HIT is an immune-mediated reaction that causes a paradoxical prothrombotic state despite the drop in platelets. Continuing heparin would worsen the condition. Notifying the provider is critical, but the nurse's first independent action is to stop the offending agent. Platelet transfusion is generally contraindicated as it can 'add fuel to the fire' and increase the risk of thrombosis.

Question 3

A critical care nurse is caring for a patient with acute lymphoblastic leukemia who recently started an aggressive chemotherapy regimen. Which set of laboratory findings would be most characteristic of Tumor Lysis Syndrome (TLS)?

Accepted Answer

Hyperkalemia, hyperphosphatemia, hyperuricemia, hypocalcemia

Answer

Tumor Lysis Syndrome (TLS) is a metabolic emergency caused by the massive and rapid death of cancer cells, releasing their intracellular contents into the bloodstream. This leads to hyperkalemia (from potassium release), hyperphosphatemia (from nucleic acid breakdown), and hyperuricemia (from nucleic acid breakdown). The high levels of phosphate bind with calcium, leading to secondary hypocalcemia.

Question 4

A patient in the ICU is receiving their first dose of a new intravenous antibiotic. Within minutes, the patient develops stridor, severe dyspnea, and a blood pressure of 70/40 mmHg. Which medication should the nurse prepare for immediate administration?

Accepted Answer

Epinephrine 0.3-0.5 mg IM

Answer

The patient is exhibiting signs of anaphylactic shock, a life-threatening allergic reaction. The first-line and most critical treatment is intramuscular epinephrine. Epinephrine acts rapidly to cause vasoconstriction (increasing blood pressure), reduce mucosal edema (relieving stridor and airway obstruction), and induce bronchodilation. While antihistamines (diphenhydramine), corticosteroids (methylprednisolone), and bronchodilators (albuterol) are also used in managing anaphylaxis, they are considered adjunctive therapies and do not replace the immediate, life-saving effects of epinephrine.

Question 5

Fifteen minutes after the initiation of a packed red blood cell (PRBC) transfusion, the patient develops a fever, chills, severe flank pain, and hypotension. The nurse suspects an acute hemolytic transfusion reaction. What is the nurse's FIRST action?

Accepted Answer

Stop the transfusion immediately.

Answer

The absolute priority and first action for any suspected transfusion reaction is to immediately stop the transfusion. This prevents the patient from receiving any more of the incompatible blood, which is causing the hemolytic reaction. After stopping the blood, the nurse should disconnect the blood tubing (while maintaining IV access with a new normal saline line), notify the provider and blood bank, monitor vital signs, and prepare to send the blood bag and tubing back for analysis.

CCRN Review Practice Test

CCRN Review Practice Test

CCRN - Review Hematology and Immunology Questions and Answers