You are performing orotracheal intubation on an average-sized, apneic adult. At what depth marking should the airway be properly positioned 2 to 3 cm above the carina?

Correct Answer: C

Rationale: The correct answer is C (19 to 23 centimeters) because the correct depth marking for an adult orotracheal intubation is typically at 21 to 23 centimeters at the teeth or 19 to 21 centimeters at the lips. Placing the tube 2 to 3 cm above the carina ensures adequate ventilation without the risk of the tube being too deep or too shallow. Choices A, B, and D are incorrect because they are outside the recommended depth range for adult orotracheal intubation, which can lead to complications such as inadequate ventilation, aspiration, or trauma to surrounding structures.

Correct Answer: C

Rationale: The correct answer is C because inducing mild hypothermia in a post-arrest patient helps reduce intracranial pressure, cerebral metabolic rate, and the brain's demand for oxygen. This is crucial in preventing secondary brain injury and improving neurological outcomes. Choice A is incorrect because hypothermia does not reduce the body's need for stored energy (sugar), but actually can lead to metabolic changes that may increase the body's energy demand. Choice B is incorrect because while hypothermia may increase blood flow to the brain and heart, it also reduces blood flow to peripheral tissues, potentially causing harm to these areas. Choice D is incorrect because hypothermia does not reduce the amount of oxygen and blood circulation needed to supply the tissues of the periphery, and in fact, can lead to decreased tissue perfusion and oxygen delivery.

Correct Answer: D

Rationale: The correct answer is D: Admit the patient to the intensive care unit. This is the most appropriate management because the 8-year-old boy has suffered a significant fall resulting in a spleen laceration, indicating a severe injury. Admitting the patient to the ICU allows for close monitoring of his condition, ensuring immediate intervention if his condition deteriorates. Option A, Type and crossmatch for blood, is not the priority in this scenario as stabilizing the patient's condition takes precedence. Option B, requesting consultation of a pediatrician, may be necessary but not as urgent as admitting to the ICU. Option C, transferring the patient to a trauma center, may delay critical care that the patient needs immediately.

Correct Answer: D

Rationale: The correct answer is D because elevated central venous pressure is not a criterion for transfer to a burn center. A, B, and C are all valid criteria for transfer based on the severity and location of burns. Criteria A and B indicate the extent of burns in terms of partial-thickness and full-thickness involvement, while C highlights specific anatomical areas that may require specialized care due to the risk of complications. Elevated central venous pressure is not typically used as a criterion for transfer to a burn center as it is not directly related to the severity or management of burns. Hence, choice D is the exception among the given criteria.

Correct Answer: D

Rationale: The correct answer is D: Is not necessary if the CT-scan of the chest is normal. Rationale: 1. The patient presents with signs of possible aortic injury (e.g., widened mediastinum) after a high-speed motor vehicle collision. 2. CT scan of the chest is a sensitive imaging modality for detecting aortic injuries. 3. If the CT scan of the chest is normal, it effectively rules out aortic injury in this scenario. 4. Performing contrast angiography would be unnecessary if the initial CT scan is normal, as it would not provide additional diagnostic value and expose the patient to further risks. Summary: A: "Is not indicated" - Incorrect, as imaging is necessary to assess for aortic injury in this high-risk scenario. B: Should be performed after CT scan of the chest - Incorrect, as contrast angiography is not necessary if the CT scan is normal. C: Is positive for aortic rupture in 80% of similar cases -