Core Nursing Explanation
Key Concept Analysis: This question tests the priority nursing intervention for a patient undergoing chemotherapy for lung cancer. The core theme is
Chemotherapy-Induced Myelosuppression. Chemotherapy drugs target rapidly dividing cells, which includes not only cancer cells but also healthy cells in the bone marrow. This leads to a decrease in the production of blood cells:
Neutropenia (low neutrophils),
Thrombocytopenia (low platelets), and
Anemia (low red blood cells). These conditions are life-threatening complications that require immediate detection and intervention.
Answer Rationale:
Key Point! Monitoring the
Complete Blood Count (CBC) daily is the priority because it is the primary tool for detecting myelosuppression early. A low absolute neutrophil count (
< 1,500/mm³, with severe neutropenia being
< 500/mm³) puts the patient at high risk for fatal infections. A low platelet count (
< 50,000/mm³) increases the risk of spontaneous bleeding. Identifying these trends allows for timely interventions like administering colony-stimulating factors (e.g., filgrastim), holding chemotherapy, or initiating protective isolation.
Distractor Analysis:
•
Watch out for confusion! Option 1 (Monitor blood glucose): While some chemotherapies (e.g., corticosteroids used as pre-medication) can cause hyperglycemia, this is not the most common or immediately life-threatening complication for most lung cancer chemotherapy regimens. It is important but not the
priority.
• Option 2 (Encourage deep breathing): This is an excellent intervention for a patient with lung cancer to prevent atelectasis and pneumonia, especially if they are sedentary. However, it is a preventive measure for a potential respiratory complication, whereas myelosuppression is a
direct, predictable, and imminent effect of the chemotherapy itself.
• Option 3 (Assess skin integrity): Chemotherapy can cause skin toxicities, and immobility from fatigue can increase pressure ulcer risk. However, like deep breathing exercises, this addresses a potential issue, not the most urgent systemic toxicity.
Related Concepts: The nursing priority is always guided by the
ABCs (Airway, Breathing, Circulation) and the principle of
Maslow's Hierarchy of Needs. A compromised bone marrow directly threatens physiological safety needs (infection, hemorrhage, hypoxia from anemia), making it a higher priority than other important but less acute concerns.
Concept Summary
•
Chemotherapy Side Effect: Myelosuppression (Bone marrow suppression).
•
Key Lab Test: Daily Complete Blood Count (CBC).
•
Critical Values to Monitor:
- Neutrophils/Absolute Neutrophil Count (ANC): Risk of infection.
- Platelets: Risk of bleeding.
- Hemoglobin/Hematocrit: Symptoms of anemia (fatigue, dyspnea).
•
Nursing Priority: Early detection of life-threatening complications over managing other side effects.
Side-by-Side Comparison!
| Complication | Primary Cause | Key Nursing Assessment | Priority Intervention |
|---|
| Myelosuppression | Chemotherapy effect on bone marrow | Daily CBC, monitor for fever, bruising, fatigue | Monitor labs, administer growth factors, implement neutropenic precautions |
| Chemotherapy-Induced Nausea/Vomiting (CINV) | Stimulation of chemoreceptor trigger zone | Assess nausea, vomiting, hydration status | Administer prophylactic antiemetics (e.g., ondansetron, aprepitant) |
| Mucositis | Effect on rapidly dividing mucosal cells | Inspect oral cavity, assess pain, ability to eat/drink | Provide frequent oral care with saline/sodium bicarbonate rinses, manage pain |
Anatomy, Physiology & Pharmacology Points
•
Physiology: The bone marrow is the site of hematopoiesis (production of RBCs, WBCs, and platelets). Chemotherapy disrupts this process.
•
Pharmacology: Common drugs for non-small cell lung cancer (e.g., cisplatin, carboplatin, pemetrexed, paclitaxel) are highly myelosuppressive.
•
Lab Values:
- Normal ANC:
1,500–8,000/mm³
- Neutropenia: ANC
< 1,500/mm³
- Severe Neutropenia: ANC
< 500/mm³ (High infection risk)
- Normal Platelets:
150,000–400,000/mm³
- Thrombocytopenia:
< 150,000/mm³
Memory Tips
•
Acronym: "CBC is KEY for CHEMO" – Chemotherapy Hurts Everything, Monitor Often.
•
Association: Think of the bone marrow as a "factory" for blood cells. Chemotherapy is like a power outage in the factory. The CBC is the "production report" you check daily to see if the factory is still running.
High-Frequency NCLEX Topics
NCLEX frequently tests on
prioritization and
management of chemotherapy side effects. You must know that monitoring for infection (neutropenia) and bleeding (thrombocytopenia) via CBC takes precedence over other supportive care measures. Questions often ask, "Which client should the nurse see first?" and the answer is typically the one with neutropenic fever or low platelet count.
Watch Out for Question Variations!
• Instead of asking for the priority intervention, the question might present a lab result (e.g., "ANC 400/mm³") and ask for the
priority nursing action (initiate neutropenic precautions/place on protective isolation).
• It could shift to
patient education: "Which instruction is most important for the nurse to give a client receiving chemotherapy?" (Answer: Report a temperature of
100.4°F (38°C) or higher immediately).
• It might combine concepts: "A client on chemotherapy has a platelet count of
18,000/mm³. Which activity should the nurse restrict?" (Answer: Shaving with a razor, due to bleeding risk).