Free Environmental & Toxicology Practice Questions

1. A severely hypothermic patient (estimated core temp below 86°F) is pulseless and apneic. You check for a pulse for 60 seconds and confirm no pulse. You begin CPR. The AED advises "No shock advised." What special considerations apply to CPR in severe hypothermia?

• Continue CPR, limit defibrillation attempts, avoid rough handling, and actively rewarm during transport; do not pronounce dead until the patient is warm and still unresponsive to resuscitation
• Stop CPR since the AED found no shockable rhythm and the patient is hypothermic
• Perform CPR at a slower rate due to the hypothermia
• Withhold CPR because chest compressions may trigger arrhythmias in hypothermia

2. Multiple patients from the same household present with headache, nausea, dizziness, and confusion. All were using a gas-powered generator inside their garage during a power outage. SpO2 readings show 98% on all patients. What is the MOST likely exposure and why are the SpO2 readings unreliable?

• Carbon monoxide poisoning; pulse oximeters cannot differentiate carboxyhemoglobin from oxyhemoglobin, producing falsely normal readings
• Natural gas leak; SpO2 readings confirm adequate oxygenation
• Food poisoning from a shared meal
• Viral illness since multiple household members are affected

3. You respond to a patient who was stung by a bee. He has no known allergies. Over the next 10 minutes, he develops generalized urticaria, throat tightness, and his blood pressure drops to 80/50. He does not have a prescribed epinephrine auto-injector. What should the EMT do?

• Contact medical direction for authorization to use a unit-dose epinephrine auto-injector (where available per protocol) or request ALS intercept; apply oxygen and transport immediately
• You cannot administer epinephrine because the patient does not have a prescription
• Administer oral glucose to raise the blood pressure
• Apply a tourniquet above the sting site

4. A patient has intentionally ingested a bottle of acetaminophen (Tylenol) approximately 2 hours ago. She is currently asymptomatic and wants to refuse transport, stating she "feels fine." What is your MOST important action?

• Strongly encourage transport; acetaminophen overdose has a delayed presentation and can cause fatal liver failure 24-72 hours later if untreated
• Since she is asymptomatic, there is no emergency; allow her to refuse
• Administer activated charcoal to bind the acetaminophen
• Have her drink water to dilute the medication and allow refusal

5. A patient was found in a closed garage with a running car. He is unresponsive with cherry-red skin. His SpO2 reads 99%. What should you know about the SpO2 reading in this scenario?

• The SpO2 is falsely elevated because pulse oximeters cannot distinguish carboxyhemoglobin from oxyhemoglobin
• The SpO2 confirms the patient has adequate oxygenation
• Cherry-red skin always indicates a normal SpO2
• The SpO2 reading proves carbon monoxide poisoning is not present