The nurse cares for a woman with pregnancy-induced hypertension (PIH) treated with magnesium sulfate. The nurse is MOST concerned if which of the following is observed?
1. Urine output decreased from 70 to 30 ml/hour.
2. Respiratory rate increased from 14 to 18/minute.
3. Hypertonic patellar reflexes.
4. Blood pressure increased from 150/90 to 170/100.