Which of the following is an important parameter to monitor while administering magnesium sulfate?

Monitoring respiratory rate and reflexes is crucial when administering magnesium sulfate because this medication can lead to respiratory depression and affect neurological function. Magnesium acts as a muscle relaxant, which can impair the respiratory muscles if levels become too high. Therefore, it is essential to keep an eye on the patient's respiratory rate to ensure they are breathing adequately.

Additionally, deep tendon reflexes are indicators of neurological status, and a decrease in these reflexes can signal magnesium toxicity. If reflexes diminish significantly, it may indicate that the magnesium sulfate level is approaching toxic levels, necessitating immediate action to protect the patient.

The other parameters mentioned, such as skin color and texture, urine output, and heart rhythm, while important in their own right, are not as directly related to the specific risks associated with magnesium sulfate administration. Skin changes could indicate allergic reactions or other issues but do not specifically signify magnesium toxicity. Monitoring urine output is important, as magnesium can affect renal function, but it is not as pressing as respiratory status and reflexes in this context. Heart rhythm monitoring is important but secondary compared to the immediate concerns of respiratory depression and loss of reflexes.