You are on-scene with a patient suspected of taking a large amount of meperidine hydrochloride. Which of the following interventions may be effective in reversing the adverse effects of the ingested medication?

Correct Answer: D

Rationale: The correct answer is D: Naloxone. Meperidine hydrochloride is an opioid analgesic, and naloxone is an opioid antagonist that can reverse opioid overdose effects by competing for opioid receptor sites. Step 1: Identify the medication ingested (meperidine). Step 2: Recognize that meperidine is an opioid. Step 3: Understand that naloxone is an opioid antagonist that can reverse opioid effects. Step 4: Administer naloxone to competitively block opioid receptors and reverse the adverse effects. Activated charcoal (A) is used for certain poisonings, not opioids. Atropine (B) is a medication used for bradycardia and not effective for opioid overdose. Romazicon (C) is a benzodiazepine receptor antagonist, not indicated for opioid overdose.

Correct Answer: C

Rationale: Step 1: Establishing a diagnosis of shock involves assessing for clinical evidence of inadequate organ perfusion, such as altered mental status, tachycardia, and cool clammy skin. Step 2: This clinical evidence is crucial as it indicates the body's organs are not receiving enough oxygen and nutrients due to poor perfusion. Step 3: Identifying inadequate organ perfusion helps differentiate shock from other conditions with similar symptoms. Step 4: The other choices are incorrect because systolic blood pressure alone is not sufficient for diagnosing shock (A), closed head injury is not a defining feature of shock (B), and response to fluid infusion is important but not the sole criterion (D). Summary: Choice C is correct as it focuses on the key clinical feature of inadequate organ perfusion, while the other choices either focus on single parameters or unrelated conditions.

Correct Answer: C

Rationale: The correct answer is C: Breath sounds. In cardiac tamponade, there may be muffled or distant heart sounds due to the accumulation of fluid around the heart, impacting its ability to pump effectively. In tension pneumothorax, breath sounds may be absent or decreased on the affected side due to lung collapse. This differentiation is important as cardiac tamponade requires emergent pericardiocentesis, while tension pneumothorax necessitates needle decompression. Choices A, B, and D are not as useful in differentiating between the two conditions. Tachycardia may be present in both conditions, pulse volume may be decreased in both, and pulse pressure may be narrowed in both due to decreased cardiac output. Breath sounds are a key differentiating factor in this scenario.

Correct Answer: D

Rationale: The correct answer is D: Performing lower extremity fasciotomies. In this scenario, the man's leg was trapped under the car for a prolonged period, leading to potential compartment syndrome. Fasciotomies can release pressure in the compartments, improving blood flow and potentially salvaging the limb. A: Applying skeletal traction may help stabilize the leg, but it does not address the underlying compartment syndrome. B: Administering anticoagulant drugs is not indicated for compartment syndrome and may increase the risk of bleeding. C: Administering thrombolytic therapy is not appropriate for compartment syndrome and may lead to further complications. In summary, lower extremity fasciotomies are the most appropriate intervention to improve chances for limb salvage in this case.

Correct Answer: D

Rationale: The correct answer is D: Presence of hemotympanum. Hemotympanum is indicative of a basilar skull fracture, which can lead to intracranial bleeding and brain injury. CT scan is necessary to evaluate for intracranial injuries in this case. A: Blood alcohol concentration is not an indication for CT in this scenario. B: A scalp laceration alone does not warrant a CT scan for traumatic brain injury. C: Mandibular fracture does not directly indicate traumatic brain injury and is not a reason for CT in this case.