A nurse is planning to teach a group of newly licensed nurses about hypermagnesemia. Which of the following manifestations should the nurse include in the teaching?

Choice A reason: Personality changes are not a typical manifestation of hypermagnesemia. Altered mental status can occur with severe electrolyte imbalances, but magnesium excess primarily affects neuromuscular and cardiovascular function rather than causing personality changes. Choice B reason: Elevated hematocrit is not associated with hypermagnesemia. Hematocrit reflects the proportion of red blood cells in blood and is influenced by hydration status, bleeding, or polycythemia, not magnesium levels. Choice C reason: Bradypnea is a hallmark manifestation of hypermagnesemia. Excess magnesium depresses neuromuscular transmission and the central nervous system, leading to decreased respiratory rate. Severe hypermagnesemia can progress to respiratory failure, making this a critical finding. Choice D reason: Peaked T waves are associated with hyperkalemia, not hypermagnesemia. Potassium excess alters cardiac conduction, while magnesium excess more commonly causes hypotension, bradycardia, and respiratory depression.