Bone marrow suppression drives most oncology items
Cytotoxic chemotherapy targets rapidly dividing cells, and it cannot distinguish malignant cells from the healthy rapidly dividing populations in bone marrow, gastrointestinal mucosa and hair follicles. That single fact explains the majority of side effects the exam tests and lets you predict complications instead of memorising drug lists.
Marrow suppression produces three consequences in a predictable order. Neutropenia raises infection risk and typically nadirs seven to fourteen days after treatment. Thrombocytopenia raises bleeding risk. Anaemia produces fatigue, pallor, dyspnoea on exertion and tachycardia. Each has its own nursing precautions and its own reporting threshold.
Mucosal injury produces stomatitis and diarrhoea. Teach clients to use a soft toothbrush or foam swab, rinse with saline or a prescribed non-alcohol solution, avoid commercial mouthwashes containing alcohol, and avoid spicy, acidic, rough or extremely hot foods. Meticulous oral care is both a comfort measure and an infection-prevention measure because the mouth is a common portal of entry.
- •Neutropenia: fever is an emergency; avoid crowds, raw foods, fresh flowers and standing water
- •Thrombocytopenia: electric razor, soft brush, no rectal temperatures, no intramuscular injections
- •Anaemia: pace activity, cluster care, monitor for orthostatic changes
- •Stomatitis: soft brush, saline rinses, avoid alcohol-based mouthwash
Neutropenic precautions in practice
Absolute neutrophil count is the number the exam expects you to interpret. Below fifteen hundred is neutropenia, below one thousand is moderate, and below five hundred is severe with a high risk of life-threatening infection. Precautions escalate accordingly and hand hygiene remains the single most effective intervention at every level.
Environmental measures include a private room where available, screening visitors for illness, avoiding fresh flowers and live plants because of soil organisms, avoiding raw or undercooked foods and unwashed produce, and removing standing water such as vases and humidifier reservoirs. Some institutions permit thoroughly washed fruit; the exam usually tests the more conservative position.
Assessment must be deliberate because signs are muted. Check the mouth, perianal area, intravenous sites and skin folds every shift. Avoid rectal temperatures, suppositories and enemas, which can cause mucosal tears that seed bacteraemia. Report any temperature elevation immediately rather than repeating it in an hour.
| Parameter | Threshold | Nursing implication |
|---|---|---|
| Absolute neutrophil count | < 500/mm³ | Severe neutropenia; fever is an emergency |
| Platelets | < 50,000/mm³ | Bleeding precautions; avoid IM injections |
| Platelets | < 20,000/mm³ | Risk of spontaneous bleeding; limit activity |
| Haemoglobin | < 8 g/dL | Symptomatic anaemia; pace activity, anticipate transfusion |
| Temperature | ≥ 38 °C once | Report immediately in neutropenic clients |
The oncologic emergencies worth memorising
Tumour lysis syndrome occurs when large numbers of malignant cells break down rapidly after treatment, releasing intracellular contents. The result is hyperkalaemia, hyperphosphataemia, hyperuricaemia and hypocalcaemia, with a risk of dysrhythmias and acute kidney injury. Prevention centres on aggressive hydration and prescribed uric acid–lowering therapy; monitoring focuses on potassium and renal function.
Superior vena cava syndrome presents with facial and upper body oedema, distended neck and chest veins, dyspnoea and a feeling of fullness in the head, often worse in the morning or when bending forward. Elevate the head of the bed, avoid upper extremity venipuncture and report promptly.
Spinal cord compression usually announces itself as new, persistent back pain, sometimes with weakness, sensory change or new bowel and bladder dysfunction. Because delay causes permanent paralysis, new back pain in a client with known malignancy is never a routine complaint.
Hypercalcaemia of malignancy produces lethargy, confusion, constipation, nausea, polyuria and muscle weakness. Treatment involves hydration with isotonic fluid and prescribed bisphosphonates; safety measures for confusion and fall risk belong in the nursing plan.
Safe handling and client teaching
Chemotherapy agents are hazardous drugs. Nurses wear chemotherapy-rated gloves and gowns when administering them and when handling body fluids for forty-eight hours after a dose. Spills are managed with a designated spill kit, and contaminated linen and waste follow the institution's hazardous protocol rather than routine disposal.
Extravasation of a vesicant agent is a tissue emergency. Stop the infusion immediately, leave the cannula in place to attempt aspiration, notify the provider and follow the agent-specific antidote and temperature protocol. Signs include swelling, burning, loss of blood return and a change in infusion flow.
Discharge teaching should be concrete. Clients need to know their nadir period, the exact temperature that triggers a call, how to avoid infection sources, when to seek help for bleeding, how to manage nausea proactively rather than reactively, and how to maintain nutrition and hydration between cycles. Written instructions with a phone number reinforce recall in clients whose concentration is affected by treatment.