Neurological Emergencies practice questions

Answer: D) Thiamine

• AIncorrect. Thiamine is needed.
• BIncorrect. Thiamine should come first or with glucose.
• CIncorrect. It doesn't treat Wernicke's.
• DCorrect. This is Wernicke encephalopathy.

Answer: A) A subdural hematoma

• ACorrect. Anticoagulants raise bleeding risk.
• BIncorrect. The change is new.
• CIncorrect. The history suggests bleeding.
• DIncorrect. Check glucose, but suspect bleeding.

Answer: A) Loss of diaphragm function from phrenic nerve involvement, causing hypoventilation or apnea

The phrenic nerve (C3 to C5) supplies the diaphragm, so a cord injury at these levels can quickly cause hypoventilation or apnea. Airway and breathing are the priority.

• ACorrect. The phrenic nerve arises from C3 to C5 and supplies the diaphragm. An injury at or above C5 can impair diaphragmatic function and cause hypoventilation, apnea or respiratory failure, so ventilatory support may be needed.
• BIncorrect. A cervical cord injury disrupts sympathetic outflow, which leads to hypotension (and often bradycardia) from unopposed parasympathetic tone, not a hypertensive tachycardic state.
• CIncorrect. Bladder dysfunction is common after spinal cord injury and needs management, but it is not the most immediate threat to life compared with loss of ventilation.
• DIncorrect. The intrinsic hand muscles are supplied mainly by C8 to T1. Losing hand function is disabling but not immediately life-threatening, unlike compromised breathing at C3 to C5.

Answer: C) Hypertensive encephalopathy

Severe hypertension with headache, confusion and visual changes, after stroke, hemorrhage, hypoglycemia and infection are excluded, indicates hypertensive encephalopathy. Lower BP in a controlled way: no more than 25% in the first hour.

• AIncorrect. A migraine aura is usually a temporary visual disturbance. It does not explain the severely elevated BP and progressive confusion, which point to brain dysfunction caused by the hypertension.
• BIncorrect. Ischemic stroke usually starts abruptly with focal neurologic deficits. This patient has a gradual, global picture with no focal deficits.
• CCorrect. Severe headache, altered mental status and visual changes developing over hours to days with markedly elevated BP is the classic presentation. Treatment is IV antihypertensives (for example, nicardipine), lowering systolic BP by no more than 25% in the first hour, then gradually toward 160/100 mm Hg over the next 2 to 6 hours.
• DIncorrect. CNS infection is in the differential, but the patient is afebrile and the main feature is severe hypertension. That makes hypertensive encephalopathy much more likely.

Answer: B) Inability to walk, with other neurologic signs

• AIncorrect. That suggests BPPV.
• BCorrect. Central causes include stroke.
• CIncorrect. That suggests peripheral causes.
• DIncorrect. That suggests an inner ear cause.

Answer: C) Multilayer retinal hemorrhages and a subdural hematoma in a 4-month-old said to have rolled off a couch

Retinal hemorrhages with subdural hematoma in an infant, together with a history (such as a short fall) that cannot explain them, strongly suggest abusive head trauma and must be reported. Birthmarks and injuries that match a child's developmental stage are expected findings.

• AIncorrect. These describe congenital dermal melanocytosis (Mongolian spots), a common birthmark that can be mistaken for bruising. It is not a sign of abuse.
• BIncorrect. A single forehead injury in a newly walking toddler, with a history that matches the mechanism, fits an accidental injury.
• CCorrect. Retinal hemorrhages and subdural hematoma are hallmark features of abusive head trauma. A short fall cannot explain these injuries in an infant. Suspected abuse must be reported to child protective services.
• DIncorrect. Bruises over bony prominences such as the shins are typical in mobile toddlers. Bruising in non-mobile infants, or in the TEN-4-FACESp areas, is what raises concern.

Answer: C) Diffuse axonal injury

• AIncorrect. The history is traumatic.
• BIncorrect. Prolonged coma suggests more injury.
• CCorrect. It may not show on early CT.
• DIncorrect. Check glucose, but suspect DAI.

Answer: A) Systematically inspect the scalp, hairline, behind the ears, neck, and skin folds

Acute ascending flaccid paralysis without fever or sensory loss after exposure to a wooded area suggests tick paralysis, which is often confused with Guillain-Barré syndrome. A careful search of the scalp, neck and skin folds, followed by complete removal of the tick, usually reverses symptoms within 24 hours.

• ACorrect. This picture suggests tick paralysis: acute ataxia, then ascending flaccid weakness, no fever, no sensory loss, and recent exposure to a wooded area. The tick is often hidden in the hair, especially on the scalp behind the ears. Removing it usually reverses the paralysis within about 24 hours, so a thorough search is essential.
• BIncorrect. Tick paralysis is often misdiagnosed as Guillain-Barré syndrome. Moving straight to a GBS workup without searching for a tick can delay the curative step. In tick paralysis, CSF protein is not elevated the way it typically is in GBS.
• CIncorrect. Tick paralysis is caused by a neurotoxin, not an infection, so antibiotics do not reverse it. The treatment is removing the tick, plus supportive care.
• DIncorrect. IVIG is a treatment for GBS. Giving it on a presumed GBS diagnosis misses tick paralysis, which resolves once the embedded tick is found and removed.

Answer: A) Negative inspiratory force of -15 cm H2O

In myasthenic crisis, serial negative inspiratory force and vital capacity measurements detect respiratory muscle failure before oxygen saturation falls. A NIF weaker than -20 cm H2O signals the need for airway support.

• ACorrect. A negative inspiratory force weaker than about -20 cm H2O (or vital capacity under about 20 mL/kg) shows serious respiratory muscle weakness, a sign of impending respiratory failure in myasthenic crisis.
• BIncorrect. Oxygen saturation can stay normal until respiratory muscle failure is far advanced, so a normal reading does not rule out impending failure.
• CIncorrect. Eye-muscle weakness is common in myasthenia gravis, but it does not measure how well the patient can ventilate.
• DIncorrect. A fast heart rate has many causes, including infection, and does not specifically measure respiratory muscle strength.

Answer: A) An overly tight collar can compress the neck veins, impede venous outflow from the head and raise intracranial pressure

A cervical collar must be correctly sized and keep the neck neutral without compressing it. A collar that is too tight can impede jugular venous outflow and raise ICP, which is especially dangerous after a head injury.

• ACorrect. Rigid cervical collars have been shown to raise intracranial pressure, which is especially harmful in head injury. A collar that is too small or too tight makes venous compression worse. The collar should be correctly sized and keep the neck neutral without compressing the neck or blocking the airway.
• BIncorrect. Collars do not lower intracranial pressure. Rigid collars are associated with raised ICP, so a collar that is too tight should be corrected right away rather than left in place.
• CIncorrect. The vertebral arteries run within bony foramina and are not compressed by an external collar. The fit concern is pressure on the neck veins and soft tissue, plus effects on the airway.
• DIncorrect. Rigid collars alone do not fully immobilize the spine and need lateral support. A poorly fitting collar also carries safety risks, including raised ICP, a harder airway or intubation, and pressure injury.