You are treating a 50-year-old male with a cardiac history currently complaining of chest pain. He is breathing at 20 times a minute, has an irregular heart rate of 136 beats per minute, and a blood pressure of 120/60. His twelve-lead-tracing indicates the presence of an ST-elevation myocardial infarction (STEMI). What makes the ST-elevation infarction treatment different from a non-STEMI patient's treatment?

Correct Answer: B

Rationale: The correct answer is B because in ST-elevation myocardial infarction (STEMI), prompt reperfusion therapy is crucial to minimize cardiac damage. As the patient has ST-elevation on the ECG, this indicates complete occlusion of a coronary artery, necessitating urgent treatment. Fibrinolytics can help dissolve the clot and restore blood flow, but timing is critical. Time is muscle in STEMI, so the door-to-balloon time or door-to-needle time should be minimized. Destination is also important as the patient needs to be transferred to a facility capable of performing percutaneous coronary intervention (PCI) if fibrinolytics are not available. Therefore, choice B is correct. Choices A and D are incorrect because non-ST elevation infarctions do not typically require fibrinolytics, and choice C is incorrect as fluid bolus is not a standard treatment for STEMI.

Correct Answer: C

Rationale: The correct answer is C: Lidocaine. Lidocaine is a Class IB antiarrhythmic drug commonly used for ventricular arrhythmias. In cardiac arrest due to ventricular fibrillation, lidocaine can be a suitable alternative to amiodarone. It works by stabilizing the cardiac cell membrane and reducing electrical activity. Epinephrine (A) is used for its vasopressor effects, not as a first-line antiarrhythmic. Cardizem (B) is a calcium channel blocker used for rate control in certain arrhythmias, not for ventricular fibrillation. Procainamide (D) is a Class IA antiarrhythmic, also used for certain arrhythmias but not typically a first-line choice for ventricular fibrillation in cardiac arrest.

Correct Answer: A

Rationale: Correct Answer: A - Transcutaneous pacing (TCP) Rationale: 1. Atropine failed to increase heart rate, indicating the need for immediate intervention. 2. Transcutaneous pacing is the next step to externally pace the heart and increase heart rate. 3. Synchronized cardioversion (B) is for unstable patients with specific arrhythmias, not for bradycardia. 4. Repeating atropine (C) may not be effective and delays necessary intervention. 5. Epinephrine (D) is typically used in cardiac arrest, not first-line for symptomatic bradycardia.

Correct Answer: D

Rationale: The correct answer is D because in a trauma situation involving a bicycle rider hit by a truck, airway management is crucial. Endotracheal intubation and ventilation ensure adequate oxygenation and ventilation, which is essential for the patient's survival. This step takes priority over other interventions like obtaining a cervical spine x-ray (A), inserting a central venous pressure line (B), or administering crystalloid solution (C). These interventions may be necessary later in the management of the patient but ensuring a secure airway and adequate breathing is the immediate priority to prevent further deterioration and improve outcomes.

Correct Answer: C

Rationale: The Rule of Nines is a method used to estimate the extent of burns on the body. For infants, the head is proportionally larger compared to adults, making up a greater percentage of the total body surface area. Therefore, when applying the Rule of Nines to infants, a larger proportion of the total body surface area is assigned to the head. This is crucial for accurate assessment and treatment of burns in infants. Choice A is incorrect as the Rule of Nines is a standard method for estimating burns. Choice B is incorrect as it is not specific to the Rule of Nines application in infants. Choice D is incorrect as the legs are not proportionally larger in infants compared to adults.