Oncologic Emergencies: SVC, Cord Compression, TLS, Hypercalcemia

Medical-Surgical · Hematology / Oncology·Updated 2026-10-28

What it is

Oncologic emergencies arise from the tumor or its treatment. They are obstructive (superior vena cava syndrome, spinal cord compression), metabolic (tumor lysis syndrome, hypercalcemia of malignancy, SIADH) or infiltrative (cardiac tamponade). Each progresses within hours to days to permanent harm or death, so the nurse's role is early recognition of subtle cues, prompt reporting, and prevention in high-risk clients.

What the NCLEX focuses on

Superior vena cava syndrome (lung cancer, lymphoma): facial, neck and periorbital edema, distended neck and chest veins, and dyspnea; stridor and altered mental status are late signs.
Spinal cord compression: new or worsening back pain, often worse lying down, is the first symptom, followed by leg weakness, sensory loss and bowel or bladder dysfunction; high-dose dexamethasone and radiation start promptly.
Tumor lysis syndrome (leukemia, lymphoma, bulky rapidly growing tumors): usually within 24 to 48 hours of chemotherapy; hyperkalemia, hyperphosphatemia, hyperuricemia and hypocalcemia lead to acute kidney injury.
Tumor lysis prevention: IV hydration and allopurinol or rasburicase before the first chemotherapy dose.
Hypercalcemia of malignancy (multiple myeloma, breast and lung cancer): fatigue, weakness, confusion, constipation, nausea, polyuria and a shortened QT; treated with IV 0.9% sodium chloride, a loop diuretic once hydrated, and a bisphosphonate or calcitonin.
SIADH (small cell lung cancer): hyponatremia, weight gain without edema, confusion and seizures; treated with fluid restriction.
Cardiac tamponade: hypotension, muffled heart sounds, jugular venous distention and pulsus paradoxus.

Priority nursing actions

Assess airway, breathing and circulation; with superior vena cava syndrome, raise the head of the bed and give oxygen.
Report new back pain or leg weakness at once, give prescribed dexamethasone, and prepare the client for MRI and radiation.
Before chemotherapy for a high-risk tumor, confirm IV hydration and allopurinol or rasburicase are in place.
Monitor intake and output, potassium, phosphorus, calcium, uric acid and creatinine, with continuous cardiac monitoring for hyperkalemia or hypercalcemia.
Give prescribed IV 0.9% sodium chloride for hypercalcemia and watch for fluid overload; institute seizure precautions for severe hyponatremia.

Numbers to know

Value	Normal	Oncologic emergency pattern
Potassium	3.5 to 5.0 mEq/L (3.5 to 5.0 mmol/L)	High in tumor lysis syndrome
Phosphorus	2.4 to 4.4 mg/dL (0.78 to 1.42 mmol/L)	High in tumor lysis syndrome
Total calcium	8.6 to 10.2 mg/dL (2.15 to 2.55 mmol/L)	Low in tumor lysis; high in hypercalcemia of malignancy
Sodium	136 to 145 mEq/L (136 to 145 mmol/L)	Low in SIADH
Urine output	At least 0.5 mL/kg/hour	A fall signals acute kidney injury in tumor lysis

Common exam traps

Choosing to restrict fluids in hypercalcemia or tumor lysis syndrome: wrong because both need IV hydration to protect the kidneys; fluid restriction belongs to SIADH.
Choosing muscle strain as the cause of new back pain in a client with cancer: wrong because back pain is the earliest sign of spinal cord compression, before weakness appears.
Choosing a potassium chloride infusion before induction chemotherapy: wrong because tumor lysis releases potassium.
Choosing to lay a client with facial swelling and dyspnea flat: wrong because superior vena cava syndrome needs head elevation to ease breathing and venous drainage.

What to teach

Report new or worsening back pain, leg weakness or numbness, or loss of bladder or bowel control immediately.
Report swelling of the face, neck or arms, a collar that feels tight, or shortness of breath.
During chemotherapy, drink the prescribed fluids and report decreased urine, muscle cramps, numbness or palpitations.
Report constipation, increased thirst, confusion or extreme fatigue.

Try 2 NCLEX-style questions on this topic

From the NCLEXPace question bank. Pick your answers, then check them inside NCLEXPace.

Question 1 · QID 11228FB6

A 67-year-old client with newly diagnosed multiple myeloma has a serum calcium of 12.8 mg/dL, reports constipation and confusion, and has a creatinine of 2.1 mg/dL. Which nursing intervention is the priority?

Select the best answer.

A. Administer prescribed IV fluids and monitor urine output closely
B. Increase dietary calcium and vitamin D intake to support bone strength while the client is being treated for multiple myeloma
C. Restrict oral and intravenous fluids to reduce renal workload until the creatinine improves and the calcium level begins to fall
D. Apply a supportive back brace and begin weight-bearing exercise to stimulate bone formation and reduce further skeletal loss

Question 2 · QID 76F7FB52

A 9-year-old client with acute lymphoblastic leukemia and a WBC count of 120,000/mm3 is about to begin induction chemotherapy. Which prescribed intervention should the nurse ensure is in place before the first dose?

Select the best answer.

A. A prophylactic potassium chloride infusion to prevent electrolyte depletion during aggressive IV hydration and chemotherapy
B. A prophylactic platelet transfusion before induction chemotherapy to reduce bleeding risk during rapid marrow suppression
C. IV hydration and allopurinol or rasburicase
D. A high-protein diet with additional phosphate-rich foods to support growth and replace nutrients during intensive chemotherapy

See the answers and full rationales

The correct answers, the reasoning for every option and 3,200+ more NCLEX questions are inside NCLEXPace. Create your account, then choose a plan to open them.

Create Account →

More tips on Medical-Surgical

Acute PancreatitisRecognize acute pancreatitis by pain and lipase, give fluids and pain control first, and catch hypocalcemia, shock and respiratory failure.Bowel Obstruction and NG Tube CareTell small from large bowel obstruction, spot strangulation early, and keep a decompression NG tube placed, patent and safe.Acute Kidney Injury vs Chronic Kidney DiseaseClassify AKI as prerenal, intrarenal or postrenal, follow its phases, and compare it with the staged, irreversible course of CKD.

Sources

Harding MM, Kwong J, Hagler D, Reinisch C. Lewis's Medical-Surgical Nursing: Assessment and Management of Clinical Problems. 12th ed. Elsevier; 2023; Chapter: Cancer.
Coiffier B, Altman A, Pui CH, Younes A, Cairo MS. Guidelines for the management of pediatric and adult tumor lysis syndrome: an evidence-based review. J Clin Oncol. 2008;26(16):2767-2778.

Practice the NCLEX questions on this topic

3,200+ NCLEX questions with think-like-a-nurse rationales, unfolding case studies and adaptive readiness exams. Start with free practice questions, then choose a plan when you are ready.