護理師準備給予心房顫動病人華法林，病人目前的 INR 為 4.5。護理師應採取什麼行動？
A nurse is preparing to administer warfarin to a client with atrial fibrillation. The client's INR is 4.5. Which action should the nurse take?
- AHold the dose and notify the provider✓ 正解暫停劑量並通知醫師
- BIncrease the dose to reverse the INR增加劑量以逆轉INR
- CAdminister the dose as scheduled按排程給予劑量
- DAdminister Vitamin K intramuscularly肌肉注射維生素K
華法林（Warfarin）治療範圍通常為 INR 2.0-3.0（心房顫動建議範圍）。若 INR 超過 4.0，代表抗凝血效果過強，出血風險大幅增加。此時應暫停給藥並通知醫師評估，切勿自行增加劑量（會加重風險）或自行投藥。護理師需透過嚴密監測 INR 值，確保病人維持在安全治療範圍內，並衛教病人警覺出血跡象。
The therapeutic range for warfarin is typically INR 2.0-3.0 (the recommended range for atrial fibrillation). An INR above 4.0 indicates excessive anticoagulant effect and a markedly increased bleeding risk. In this situation, the dose should be held and the provider notified for evaluation; the nurse must not independently increase the dose (which would worsen the risk) or administer additional medication. The nurse should closely monitor INR values to ensure the client remains within the safe therapeutic range and educate the client to watch for bleeding signs.