一位病人診斷為低血容性休克。護理師應預期會出現哪種補償機制？

低血容性休克（Hypovolemic shock）是由於循環血容量不足，導致組織灌流（tissue perfusion）不足，細胞缺氧。身體會啟動一系列代償機制以維持生命重要器官的血液供應。其中最直接且快速的反應是交感神經系統的活化，釋放腎上腺素（epinephrine）和正腎上腺素（norepinephrine），導致心跳加快（tachycardia）和周邊血管收縮（peripheral vasoconstriction）。這些反應旨在增加心輸出量（cardiac output）並將血液重新分配至心臟、大腦等關鍵器官，以暫時維持血壓和灌流。護理師應預期病人會出現這些代償性生理變化。 正確答案 B 指出心跳加快，這是低血容性休克最常見且重要的代償機制之一，目的是在血容量減少的情況下，透過增加每分鐘心搏次數來維持心輸出量，確保器官灌流。理解這些代償機制對於早期識別休克和評估治療效果至關重要。

Hypovolemic shock results from inadequate circulating blood volume, leading to insufficient tissue perfusion and cellular hypoxia. The body activates a series of compensatory mechanisms to maintain blood supply to vital organs. The most direct and rapid response is activation of the sympathetic nervous system, with release of epinephrine and norepinephrine, leading to tachycardia and peripheral vasoconstriction. These responses are intended to increase cardiac output and redistribute blood to critical organs such as the heart and brain, temporarily maintaining blood pressure and perfusion. The nurse should expect to see these compensatory physiologic changes. The correct answer B, increased heart rate, is one of the most common and important compensatory mechanisms in hypovolemic shock, designed to maintain cardiac output and ensure organ perfusion despite reduced blood volume by increasing the number of beats per minute. Understanding these compensatory mechanisms is critical for early recognition of shock and for evaluating the effectiveness of treatment.