Correct Answer: D

Rationale: The correct answer is D: Ventricular tachycardia. Ventricular tachycardia is a serious arrhythmia that can lead to palpitations, dizziness, and syncope due to the rapid and abnormal heart rhythm originating in the ventricles. This arrhythmia can be life-threatening if not promptly treated. A: Stable angina is characterized by chest discomfort or pain due to reduced blood flow to the heart muscle, usually during physical exertion or stress. It does not typically present with palpitations, dizziness, or syncope. B: Unstable angina is a more severe form of angina where symptoms occur even at rest. While it can lead to serious complications like heart attack, it does not commonly present with palpitations, dizziness, or syncope. C: Atrial fibrillation is a common arrhythmia originating in the atria, leading to an irregular and often rapid heartbeat. While it can cause palpitations and dizziness,

Correct Answer: A

Rationale: Correct Answer: A - sterile clamps Rationale: 1. **Immediate action**: Sterile clamps are essential to clamp the chest tube to prevent air from entering the pleural space. 2. **Prevent lung collapse**: Clamping the tube will prevent lung collapse and maintain positive pressure in the pleural space. 3. **Buy time**: By clamping the tube, you buy time to properly reattach the tube or secure it with a new connection. 4. **Safety**: Sterile clamps are a quick and effective solution to prevent a potentially life-threatening situation. Summary of other choices: B: Sterile dressing - Not the first priority as the immediate concern is preventing air from entering the pleural space. C: Another chest tube - Not necessary initially as clamping can buy time to reattach the disconnected tube. D: A bottle of sterile water - Not needed for emergency management of a disconnected chest tube.

Correct Answer: C

Rationale: The scenario described in the question is consistent with acute cholecystitis, which is inflammation of the gallbladder usually caused by an impacted gallstone in the cystic duct. The key clinical features of acute cholecystitis include fever, chills, right upper quadrant abdominal pain (which can be localized to the right upper quadrant), tenderness in the right upper abdomen, and a positive Murphy's sign (pain and inspiratory arrest upon palpation of the right upper quadrant). This condition is more common in pregnant women due to hormonal changes that can lead to gallstone formation and subsequent inflammation of the gallbladder. Ectopic pregnancy, pelvic inflammatory disease, and ovarian torsion typically present with different clinical features compared to those described in acute cholecystitis.

Correct Answer: A

Rationale: The correct answer is A: Ceftriaxone and azithromycin. Ceftriaxone covers Streptococcus pneumoniae, the most common pathogen in CAP, while azithromycin covers atypical pathogens like Mycoplasma pneumoniae. Vancomycin and piperacillin/tazobactam (choice B) are not first-line treatments for CAP. Ampicillin-sulbactam and levofloxacin (choice C) cover some pathogens but not as comprehensively as ceftriaxone and azithromycin. Clindamycin and cefepime (choice D) do not provide adequate coverage for typical CAP pathogens.

Correct Answer: B

Rationale: The correct answer is B: Persons who have the disease. Sensitivity measures how well a test correctly identifies individuals who have the disease (true positives). It is essential in determining the test's ability to detect the presence of the disease accurately. Choices A, C, and D are incorrect because sensitivity focuses on correctly identifying individuals who have the disease, not those with symptoms, those without the disease, or those with a diagnosis of the disease.