Answer
Almost normal blood pressure, after blood loss, does that necessarily mean that the patient's tissues are being adequately supplied with blood. In a case where there is accompanying significant increase in systemic vascular resistance (SVR), tissue perfusion may be inadequate.
Work Step by Step
Blood loss may cause the circulatory system to respond in two ways. First arterioles will constrict with resultant increase in systemic vascular resistance(SVR). In addition, veins will also constrict and this will decrease venous return. These two responses will tend to boost the falling blood pressure to near normal levels. Sympathetic stimulation will not only cause vascular smooth muscle contraction but it will induce secretion of catecholamines from the adrenal medulla. The increase in SVR will decrease blood flow to the tissues and cause impaired tissue perfusion, which will deprives cells of adequate supplies oxygen and nutrients.
