Oncologic emergencies: structural and treatment-related

Lung cancer, non-small cell and small cell together, accounts for roughly three of every four malignant cases, because central tumors and mediastinal nodes sit right against the SVC.

Mediastinal germ cell tumors can compress the SVC in young men, but they are a small share of cases.

Lymphoma is the second most common malignant cause, which makes it tempting, but it is far less frequent than lung cancer.

Breast cancer causes SVC syndrome mainly through mediastinal node metastases and is an uncommon cause overall.

Metastases can cause headache, but they do not worsen with bending or lying flat the way venous congestion does.

A positional headache with confusion in SVC obstruction means blood cannot drain from the head and the brain is swelling, a sign of severe, emergent SVC syndrome.

Stroke causes sudden focal deficits; a positional headache with diffuse confusion points to venous outflow obstruction.

Steroids can cause agitation or delirium, but they do not explain a headache that changes with head position.

Diuretics do little for edema caused by SVC obstruction and are risky in a patient showing signs of low volume.

Giving fluid and then removing it makes no sense; the order needs to be clarified before either step.

Changing the diuretic does not answer the real problem, which is that this patient should not be diuresed now.

The swelling comes from blocked venous return, not excess body water, and the low pressure, fast pulse, and low urine output suggest the patient is already dry; a diuretic could cause hypotension and kidney injury.

Either arm drains to the SVC through the brachiocephalic veins, so the left side gives no advantage.

Veins below the diaphragm drain to the inferior vena cava, so fluids and drugs reach the heart instead of pooling behind the obstruction.

The jugular veins drain directly into the blocked SVC, so infusions there add to head and neck swelling.

Arm veins feed the obstructed SVC, which slows delivery and raises the risk of thrombosis and extravasation.

With an unstable spine, any twist can push bone or tumor further into the cord, so the patient is turned and moved as one unit with the spine kept straight.

Walking loads an unstable spine and risks sudden, permanent paralysis.

Sharp bed elevation flexes the spine; position changes follow spine precautions.

Dexamethasone reduces cord edema and is continued during radiation; stopping it removes protection.

Steroids usually increase appetite, so this teaching is backward.

Evening doses cause insomnia; the dose is given in the morning or early in the day.

After more than a few days at high dose, steroids are tapered; stopping suddenly risks adrenal crisis and rebound cord edema.

High-dose dexamethasone often raises blood glucose; thirst and frequent urination are early signs that need checking.

The lumbosacral spine is the second most common site, at about a fifth to a quarter of cases.

The cervical spine accounts for only about one case in ten.

About two thirds of cases occur in the thoracic spine, which is the longest segment and has the narrowest canal relative to the cord.

The cord ends near L1 to L2, so lower lesions compress the cauda equina rather than the cord itself.

A change in level of consciousness, even subtle restlessness or confusion, comes before pupil and vital sign changes.

Abnormal breathing patterns reflect brainstem compression and appear late.

These vital sign changes are a late brainstem response, seen when herniation is imminent.

A blown pupil means the third cranial nerve is compressed by herniation, a late and ominous sign.

A held breath during the move closes the airway and builds chest pressure, which backs blood up into the skull and raises ICP.

Pushing hard with the legs is isometric straining that raises abdominal and chest pressure; staff move the patient with a draw sheet instead.

Steady breathing out keeps the airway open, so chest pressure does not climb and blood keeps draining from the head while the patient is moved.

Bending the neck forward kinks the jugular veins, so blood backs up in the skull and pressure climbs.

A blocked inner cannula is the most common cause, and removing it can restore the airway at once; if a catheter still will not pass, the cuff is deflated next.

Cuff deflation is the next step if the airway stays blocked after the inner cannula is out, not the first.

More oxygen cannot reach the lungs through a blocked tube; the block has to be cleared first.

Saline instillation does not clear a plug and can push secretions deeper; it is not recommended.

Stridor comes from narrowing at or below the larynx; mouth suction does not relieve it.

An outpatient scope delays care for an airway emergency.

Stridor with low oxygen saturation means a critical upper airway narrowing; help is called and oxygen given before anything else.

Steroids may reduce swelling over hours, but they do not secure an airway that is closing now.

Blood pressure falls, not rises, as tamponade develops; the compensation is in the pericardium.

Given weeks, the pericardial sac adapts and stretches, so it can hold a liter or more before pressure rises enough to compress the heart.

The heart speeds up to keep output as filling falls; slowing would worsen tamponade.

Pericardial fluid is not cleared through the lungs; it stays in the sac until it is drained.

Hearing loss is a cisplatin toxicity.

Hemorrhagic cystitis comes from ifosfamide and high-dose cyclophosphamide, not mTOR inhibitors.

Pneumonitis is a class effect of mTOR inhibitors; new cough or shortness of breath is reported promptly so the drug can be held and steroids considered.

Neuropathy is typical of taxanes, platinum drugs, vinca alkaloids, and bortezomib.

Both catheters drain the bladder, which is already empty here; neither reaches urine trapped above blocked ureters.

Dialysis treats the uremia but leaves the blockage in place; relieving the obstruction is what can restore kidney function.

Fluids and a diuretic cannot push urine past a mechanical block; they add fluid overload in an anuric patient.

The block sits above the bladder, so urine has to be diverted from the kidneys themselves, by stents passed through the ureters or by tubes placed through the back into each kidney.

Once bile flows again, less conjugated bilirubin spills into the urine within days, while bilirubin already deposited in the skin and eyes takes 1 to 2 weeks or more to fade.

Bilirubin bound in the skin and sclera clears slowly; expecting it gone in a day can make the patient think the drainage failed.

Itching usually eases within days of good drainage; itching that keeps getting worse suggests the duct is blocked again and is reported.

No special diet is required once bile reaches the gut, and cutting fat only lowers calories in a patient who is often already losing weight.