You are on-scene with a 40-year-old patient with an extensive cardiac history for his age. Today, he is complaining of chest pain that radiates to his jaw and left arm. His vital signs are stable; however, once on the cardiac monitor, he exhibits ST elevation in leads II, III, and aVf. With the EKG finding, which of the following should you suspect?

Correct Answer: B

Rationale: The correct answer is B: An inferior wall myocardial infarction. The EKG findings of ST elevation in leads II, III, and aVf indicate an inferior wall MI. Leads II, III, and aVf correspond to the inferior wall of the heart supplied by the right coronary artery. This pattern of ST elevation is indicative of myocardial ischemia or infarction in this region. The symptoms of chest pain radiating to the jaw and left arm are also classic for a heart attack. A: A possible aortic dissection is unlikely in this case as the EKG findings specifically point towards a myocardial infarction rather than aortic pathology. C: A possible pulmonary embolus is less likely as the EKG findings are more consistent with a myocardial infarction, and pulmonary embolism typically presents with symptoms such as shortness of breath and chest pain. D: A septal wall myocardial infarction is not supported by the

Correct Answer: B

Rationale: The correct answer is B: To prevent atelectasis from occurring at the end of exhalation. Pursed lips and sighing-type respirations help create positive pressure in the airways, preventing collapse of small airways and maintaining lung inflation. Pursed lips prolong exhalation, which helps keep airways open, reducing the risk of atelectasis. Choices A, C, and D are incorrect because pursed lips and sighing-type respirations do not directly relate to expelling foreign bodies, preventing pleural friction rub, or increasing the size of air sacs in the lungs.

Correct Answer: D

Rationale: The correct answer is D because performing diagnostic peritoneal lavage or a FAST exam is crucial in evaluating for intra-abdominal injuries after blunt trauma. This will help determine if there is internal bleeding or organ damage requiring immediate intervention. A: Performing external fixation of the pelvis is not the immediate priority in this scenario as internal injuries need to be ruled out first. B: Obtaining abdominal and pelvic CT-scans may provide detailed information, but they are time-consuming and not the immediate priority for a potentially unstable patient. C: Performing arterial embolization of the pelvic vessel is not the initial priority as the patient's internal injuries need to be evaluated first.

Correct Answer: D

Rationale: The correct answer is D: Urinary output. Urinary output is the most reliable guide to volume replacement during resuscitation because it directly reflects the perfusion of vital organs and the body's ability to eliminate excess fluid. Adequate urinary output indicates effective fluid resuscitation, while decreased urinary output may indicate inadequate perfusion and the need for further volume replacement. Monitoring urinary output helps ensure appropriate fluid balance and prevents complications such as fluid overload or organ damage. Other choices are not as reliable for volume replacement guidance: A: Heart rate can be influenced by various factors such as pain, stress, medications, and underlying medical conditions. B: Hematocrit reflects the concentration of red blood cells in the blood, which may not accurately reflect volume status during resuscitation. C: Blood pressure can be affected by many factors such as medications, pain, and underlying conditions, making it less reliable as a sole guide for volume replacement.

Correct Answer: B

Rationale: The correct answer is B: Rewarm. The priority for a burn victim with a core temperature of 34°C is to rewarm the body to prevent hypothermia, which can worsen the patient's condition. Escharotomy is a surgical procedure to relieve pressure from burns, not related to temperature. Oxygen mask may be needed but warming is the immediate concern. IV narcotics are not indicated for hypothermia.