A nurse is to administer a hypotonic solution to a patient with a critically high sodium. Which solution is hypotonic?

Choice A reason: H2-receptor antagonist and two antibiotics is not the correct combination for the "triple therapy" regimen. H2-receptor antagonists are drugs that block the action of histamine on the stomach cells, reducing the production of acid. They are used to treat peptic ulcers, but they are not effective against H. pylori bacteria. The "triple therapy" regimen requires an antibiotic to kill the bacteria, and a proton-pump inhibitor to reduce the acid secretion and promote healing.

Choice B reason: Two proton-pump inhibitors and an antibiotic is not the correct combination for the "triple therapy" regimen. Proton-pump inhibitors are drugs that block the enzyme that produces acid in the stomach, lowering the acidity and allowing the ulcer to heal. They are used to treat peptic ulcers, but they are not enough to eradicate H. pylori bacteria. The "triple therapy" regimen requires two antibiotics to kill the bacteria, and one proton-pump inhibitor to reduce the acid secretion and promote healing.

Choice C reason: H2-receptor antagonist, proton pump inhibitor, and an antibiotic is not the correct combination for the "triple therapy" regimen. H2-receptor antagonists and proton-pump inhibitors have similar effects on the stomach acid, but they work in different ways. They are both used to treat peptic ulcers, but they are not necessary to use together. The "triple therapy" regimen requires two antibiotics to kill the bacteria, and one proton-pump inhibitor to reduce the acid secretion and promote healing.

Choice D reason: Proton-pump inhibitor and two antibiotics is the correct combination for the "triple therapy" regimen. Proton-pump inhibitors are drugs that block the enzyme that produces acid in the stomach, lowering the acidity and allowing the ulcer to heal. They are used to treat peptic ulcers, and they also enhance the effectiveness of the antibiotics. The "triple therapy" regimen requires two antibiotics to kill the H. pylori bacteria, and one proton-pump inhibitor to reduce the acid secretion and promote healing. The most common antibiotics used are amoxicillin, clarithromycin, and metronidazole.

Choice A reason: This is not a correct answer because 0.9% Sodium Chloride is an isotonic solution, which means it has the same osmolarity as the blood plasma. It does not cause any fluid shifts between the intracellular and extracellular compartments.

Choice B reason: This is not a correct answer because Lactated Ringer's is an isotonic solution, which means it has the same osmolarity as the blood plasma. It does not cause any fluid shifts between the intracellular and extracellular compartments.

Choice C reason: This is not a correct answer because D5W (5% Dextrose in Water) is an isotonic solution when it is in the IV bag, but it becomes hypotonic once it enters the body, as the dextrose is rapidly metabolized and only water remains. However, it is not a preferred solution for a patient with critically high sodium, as it can cause cerebral edema and worsen the neurological status.

Choice D reason: This is a correct answer because 0.45% Sodium Chloride is a hypotonic solution, which means it has a lower osmolarity than the blood plasma. It causes fluid to shift from the extracellular to the intracellular compartment, which can help lower the sodium level and correct the fluid imbalance.