You are transporting a 20-year-old pregnant female from a local hospital to a medical facility that specializes in high-risk pregnancies when you note the patient is experiencing unexplained hypotension and bradycardia. The patient has a patent IV and is being administered magnesium that was initiated by hospital staff. On the cardiac monitor, the patient presents with a lengthening PR interval and signs of an impending high-degree nodal block. Which of the following interventions would be most appropriate in this case?

Correct Answer: B

Rationale: The correct answer is B: Stop the magnesium sulfate infusion immediately, and administer the appropriate dose of calcium chloride to correct the adverse effects of magnesium toxicity. Rationale: 1. **Stop magnesium infusion**: Magnesium toxicity can cause hypotension, bradycardia, and high-degree nodal block, hence stopping the infusion is crucial. 2. **Administer calcium chloride**: Calcium is the antidote for magnesium toxicity as it competes with magnesium for binding sites, reversing its effects. 3. **Corrects adverse effects**: Calcium chloride helps in counteracting the negative effects of magnesium on the cardiovascular system. Summary: - **Option A**: Increasing magnesium and giving saline won't address magnesium toxicity. - **Option C**: Potassium won't counteract magnesium toxicity. - **Option D**: Reducing infusion and giving dextrose won't correct magnesium toxicity.

Correct Answer: A

Rationale: The correct answer is A because a critical burn is determined by the percentage of total body surface area (TBSA) affected. In this case, a 10-year-old patient with superficial burns over 60% of the body meets the criteria for a critical burn due to the extensive TBSA involvement. Superficial burns over 60% of the body can lead to significant fluid loss, infection risk, and systemic complications. Choice B is incorrect because full-thickness burns on a specific area of the arm, even if full-thickness, are not as extensive as 60% TBSA involvement. Choice C is incorrect as partial-thickness burns across 25% of the body, not involving critical areas, do not meet the criteria for a critical burn based on TBSA. Choice D is also incorrect as partial-thickness burns on 25% of the body, not involving critical areas, do not meet the criteria for a critical burn based on TBSA.

Correct Answer: C

Rationale: The correct answer is C: An advanced directive. An advanced directive is a legal document that allows an individual to specify their medical treatment preferences in case they are unable to make decisions. It includes instructions on the use of life-sustaining treatments. A: A do not resuscitate order (DNR) specifically addresses whether or not to perform cardiopulmonary resuscitation in case of cardiac arrest, but it does not cover overall medical treatment preferences. B: A will is a legal document that specifies how a person's assets and properties should be distributed after their death, not their medical treatment preferences. D: A personal directive is a general term that may refer to various legal documents but does not specifically address medical treatment preferences.

Correct Answer: C

Rationale: The correct answer is C: Control internal hemorrhage operatively. In managing a gunshot wound to the abdomen, the priority is to control internal bleeding, usually through surgical intervention. Administering O-negative blood (A) is important for resuscitation but does not address the primary issue. External warming devices (B) are not the priority in this scenario. Applying a pneumatic antishock garment (PASG) (D) is not recommended as it could delay necessary surgical intervention to control hemorrhage. Operating to control internal hemorrhage is crucial to prevent further blood loss and stabilize the patient's condition.

Correct Answer: D

Rationale: The correct answer is D because in a patient with flail chest, which is a serious condition involving multiple rib fractures leading to paradoxical chest wall movement, mechanical ventilation is essential to support adequate ventilation and oxygenation. Endotracheal intubation helps secure the airway and allows for positive pressure ventilation to improve gas exchange. This is crucial in preventing respiratory failure and ensuring adequate oxygen delivery to tissues. Choice A is incorrect as confusion is not an indication for Ringers lactate solution. Choice B, cyanosis, does not address the need for ventilatory support in flail chest. Choice C, tachypnea, is a symptom of respiratory distress but does not address the need for mechanical ventilation, which is the definitive management for flail chest.