A patient with heart failure is prescribed digoxin. Which electrolyte imbalance increases the risk of digoxin toxicity?

Correct Answer: C

Rationale: Hypokalemia (low levels of potassium) increases the risk of digoxin toxicity. This is because digoxin competes with potassium for binding sites on the sodium-potassium ATPase pump in the cell membrane. When potassium levels are low, there is an increased binding of digoxin to these pumps, leading to enhanced entry of calcium into the cells. This can result in an increased intracellular calcium concentration, leading to digoxin toxicity and potential cardiac arrhythmias. Therefore, monitoring and correcting potassium levels is crucial in patients prescribed digoxin to reduce the risk of toxicity.

Correct Answer: C

Rationale: The presentation described in the question (sensation of fullness and pressure in the left ear, hearing loss, occasional tinnitus, retracted tympanic membrane with decreased mobility on pneumatic otoscopy) is suggestive of serous otitis media, also known as otitis media with effusion. Serous otitis media occurs when fluid accumulates in the middle ear without signs of infection. This buildup of fluid in the middle ear space can cause the tympanic membrane to retract and reduce its mobility on pneumatic otoscopy.

Correct Answer: D

Rationale: Filipinos have generally low awareness about osteoporosis. Despite the increasing number of cases in the country, many Filipinos still lack knowledge about the disease and its risk factors. Osteoporosis is a significant health concern in the Philippines, especially among the elderly population, but there is still a need for more education and awareness campaigns to improve prevention and management strategies.

Correct Answer: C

Rationale: Hypokalemia (low levels of potassium) increases the risk of digoxin toxicity. This is because digoxin competes with potassium for binding sites on the sodium-potassium ATPase pump in the cell membrane. When potassium levels are low, there is an increased binding of digoxin to these pumps, leading to enhanced entry of calcium into the cells. This can result in an increased intracellular calcium concentration, leading to digoxin toxicity and potential cardiac arrhythmias. Therefore, monitoring and correcting potassium levels is crucial in patients prescribed digoxin to reduce the risk of toxicity.

Correct Answer: D

Rationale: The presentation of sudden-onset severe headache, vomiting, and altered mental status, along with the presence of a berry-shaped aneurysm on imaging, point towards a diagnosis of subarachnoid hemorrhage. The most common cause of a subarachnoid hemorrhage is the rupture of a saccular (berry) aneurysm, which commonly occurs at the junction of the anterior communicating artery and anterior cerebral artery. The sudden headache is often described as the "worst headache of my life" and is typically associated with nausea and vomiting. Altered mental status may be present due to the effects of increased intracranial pressure and possible associated brain injury. It is important to promptly diagnose and manage subarachnoid hemorrhage to prevent complications such as vasospasm, rebleeding, and ischemic deficits.