Correct Answer: A

Rationale: The correct answer is A because abruptly stopping steroids can lead to adrenal insufficiency due to suppression of the adrenal glands. This can result in a sudden drop in cortisol levels, which are essential for various physiological functions. Patients on long-term steroid therapy need a gradual taper to allow the adrenal glands to resume cortisol production. Choices B, C, and D are incorrect as they do not directly relate to the physiological effects of stopping steroids abruptly.

Correct Answer: C

Rationale: The correct answer is C: platelets 18,000. A critically low platelet count can lead to life-threatening bleeding in the ICU. Normal platelet count ranges from 150,000 to 450,000. A count of 18,000 indicates severe thrombocytopenia. Immediate reporting is crucial for prompt intervention. Rationale for why other choices are incorrect: A: Hematocrit of 48% is within normal range (male: 42-52%, female: 37-47%). B: paCO2 of 38 mm Hg is within normal range (35-45 mm Hg). D: WBC count of 8000 is within normal range (4000-11000/uL). In critical care settings, it is vital to prioritize and address life-threatening conditions promptly, hence the urgent need to report the critically low platelet count.

Correct Answer: A

Rationale: The correct answer is A: Bacterial meningitis. Bacterial meningitis is the most significant form due to its potential severity and rapid progression, requiring urgent medical intervention with antibiotics. Bacterial meningitis can lead to serious complications such as brain damage or death if left untreated. Septic meningitis (choice B) refers to meningitis caused by a systemic infection spreading to the meninges. Aseptic meningitis (choice C) is typically viral or non-bacterial in origin, usually milder than bacterial meningitis. Viral meningitis (choice D) is less severe than bacterial meningitis and often resolves on its own without specific treatment.

Correct Answer: A

Rationale: Rationale: - Salt tablets are used for mild deficits of serum sodium to help restore electrolyte balance. - Sodium is crucial for fluid balance, nerve function, and muscle contraction. - Severe deficits of serum magnesium, potassium, and calcium require specific electrolyte replacement therapy, not salt tablets. Summary: - Choice A is correct because salt tablets are used for mild deficits of serum sodium. - Choices B, C, and D are incorrect because they involve severe deficits of different electrolytes that require specific replacement therapy.

Correct Answer: C

Rationale: The correct answer is C: Autoantibodies. In Hashimoto's thyroiditis, the immune system mistakenly attacks the thyroid gland by producing autoantibodies against thyroid proteins such as thyroglobulin and thyroid peroxidase. These autoantibodies lead to inflammation and destruction of thyroid tissue. Antigen-antibody complexes (choice A) are not the main mechanism in Hashimoto's thyroiditis. Viral (choice B) and bacterial infections (choice D) do not directly cause autoimmune destruction of the thyroid in this condition. Autoantibodies targeting the thyroid gland are the key pathogenic factor in Hashimoto's thyroiditis.