一位高血壓病史並因妊娠毒血症接受靜脈輸注硫酸鎂的病人，下列哪項評估結果需要立即採取介入措施？
A nurse is assessing a client with a history of hypertension who is receiving an IV infusion of magnesium sulfate for preeclampsia. Which assessment finding requires immediate intervention?
- AAbsent patellar deep tendon reflexes✓ 正解膝腱反射消失
- BUrine output of 40 mL/hr尿液輸出量 40 mL/hr
- CRespiratory rate of 14 breaths/min呼吸頻率 14 次/分
- DSerum magnesium level of 6 mg/dL血清鎂濃度 6 mg/dL
硫酸鎂中毒的首要臨床徵象為深層肌腱反射消失（Patellar reflex absent），這通常發生在呼吸抑制之前。正常治療範圍內血鎂約在 4-8 mg/dL，反射消失暗示血鎂濃度過高，可能即將進入心臟與呼吸抑制階段，必須立即停止輸注並備妥鈣離子拮抗劑。
Absent patellar deep tendon reflexes are an early sign of magnesium sulfate toxicity and require immediate intervention, typically stopping the infusion and preparing calcium gluconate. While a respiratory rate of 14 and urine output of 40 mL/hr are within acceptable limits, loss of reflexes indicates dangerously high serum levels that can progress to respiratory depression.
美台對硫酸鎂的使用監測均非常嚴謹，美國護理師常需依據監測結果自主暫停給藥並回報，台灣則多遵循醫師口頭或書面醫囑進行調整。