10 free Paramedic practice questions: Advanced Differential Diagnosis

Correct answer · The thyroid surgery 4 days ago

Sepsis and thyroid storm share almost everything on this call: fever, a fast rhythm, altered mentation, and a patient who is clearly sick. Reach for the finding only one of them can claim. Surgery is a recognized precipitant of thyroid storm, and thyroid surgery most of all, so that one line in the history does double duty: it tells you this patient had thyroid disease worth operating on, and it hands you the stressor that set the storm off. The rest of the findings sit on both sides of the differential, which makes them useless for telling the two apart even though they are what makes the patient sick. That is the move worth keeping. When two conditions predict the same findings, the shared findings cannot decide between them, so you go looking for the one thing only one candidate explains.

Correct answer · Giving diltiazem to slow the ventricular response

Calcium channel blockers and other AV nodal blocking agents are meant for a narrow complex tachycardia that is genuinely supraventricular. This patient has a prior infarction and a QRS that is not clearly narrow, which puts ventricular tachycardia squarely on the list. If the rhythm is ventricular, an AV nodal blocker does nothing to the ventricular focus, and diltiazem still vasodilates and weakens the contraction that is holding this pressure up, which can drop this patient into profound refractory hypotension. That is why these agents are held whenever the origin of the rhythm is uncertain rather than given by default to any fast rhythm that looks close to narrow.

Correct answer · Crackles at both lung bases with distended neck veins

Cardiogenic pulmonary edema is fluid backing up into the alveoli behind a failing left ventricle, so the auscultatory signature is crackles that start at the bases and move upward. Distended neck veins add the systemic-venous half of the picture, showing that the right side of the heart is also facing elevated pressure. Each of the other option sets points somewhere else in the respiratory-distress differential: airflow obstruction, a pleural-space problem, and a metabolic problem. Sorting difficulty breathing by which compartment the findings come from is the first step in a paramedic differential.

Correct answer · Opioid toxicity

Slow, shallow respirations, constricted pupils, and depressed responsiveness together form the pattern of opioid toxicity, and the low SpO₂ with an adequate blood glucose level points to a ventilation problem rather than a metabolic one. Cause-hunting in altered mental status works by running a structured list of causes and letting measured findings remove candidates: a blood glucose level of 96 mg/dL removes hypoglycemia, and neither a postictal state nor an ischemic stroke produces symmetric miosis with a respiratory rate of 6. Naming the cause changes management immediately, because the first priority is supporting ventilation and oxygenation, with naloxone titrated to restore adequate breathing rather than full arousal.

Correct answer · Carbon monoxide poisoning

Three people in one dwelling with the same nonspecific symptoms during heating season, in a home warmed by a fuel-burning appliance, is the presentation that defines carbon monoxide poisoning until proven otherwise. The reassuring SpO₂ of 99% is the trap: a standard pulse oximeter cannot distinguish carboxyhemoglobin from oxyhemoglobin, so it reports a normal saturation while oxygen delivery to the tissues is severely impaired. A shared exposure pattern is a cue about the environment rather than about any one patient, and it outweighs a single reassuring number. Children decompensate sooner than adults at the same exposure because of their higher metabolic rate and minute ventilation.

Correct answer · Inability to raise the affected eyebrow

The forehead receives motor input from both cerebral hemispheres, so a lesion above the facial nerve nucleus (a cortical stroke) weakens the lower face while forehead movement stays intact. A lesion of the facial nerve itself, as in Bell palsy, paralyzes the entire half of the face, including eyebrow elevation and eyelid closure. Inability to raise the eyebrow on the weak side therefore localizes the problem to the nerve rather than the brain. Isolated facial weakness with normal speech and limb strength supports the same conclusion, but forehead involvement is the single discriminating finding.

Correct answer · Steady improvement in strength over 30 minutes

Todd paralysis is a transient focal deficit that follows a seizure, produced by temporary exhaustion of the cortex that generated the seizure. Its defining behavior is recovery: strength returns over minutes to hours, so serial neurologic examinations showing measurable improvement point to a postictal cause. Acute ischemic stroke behaves the opposite way, with deficits that are abrupt and maximal at onset and do not steadily improve in the field. Because a stroke can itself provoke a seizure, Todd paralysis remains a working impression the paramedic reassesses, not a reason to slow the evaluation.

Correct answer · Posterior circulation stroke

Strokes in the vertebrobasilar territory present with balance, eye movement, and coordination findings rather than the face, arm, and speech findings the classic screen looks for. Abrupt vertigo combined with gait ataxia and double vision localizes to the brain stem or cerebellum, and abrupt onset is the vascular signature. Balance and eye findings were added to stroke recognition teaching precisely because the face-arm-speech screen misses these patients. Treating this presentation as an inner ear problem costs the patient a treatment window.

Correct answer · Delirium from an acute medical illness

Delirium is an acute, fluctuating disturbance of attention and awareness produced by an underlying medical problem: infection, a medication effect, hypoxia, or a metabolic derangement. The distinguishing feature is the time course: a change from the patient's own baseline over hours to days, often with hallucinations and a drifting level of consciousness. Dementia, by contrast, declines gradually over months to years and does not worsen overnight. Recognizing the acute change as delirium is what drives the paramedic to search for the treatable cause instead of accepting that the patient is "confused at baseline."

Correct answer · Widespread vasodilation lowering vascular resistance

An infection that reaches the bloodstream releases mediators that relax arterioles everywhere, so vascular resistance falls and blood pressure falls with it while the heart speeds up to compensate. Because the peripheral vessels stay open rather than clamping down, the skin remains warm, dry, and flushed and the pulse pressure widens: the opposite of what compensation for lost volume or a failing pump looks like. Flat neck veins and clear lungs say nothing is backing up behind the heart, which removes pump failure and obstruction from consideration. Recognizing the resistance problem matters because these patients need volume first and vasoconstriction second.