<International Circulation>: There is some evidence that patients who continue to bleed in the brain have higher blood pressures. Is there an explanation for this phenomenon?
 
   《 国际循环》：  有证据表明，持续脑出血患者往往血压较高，如何解释这一现象?

    Prof Carmelo Graffagnino: The initial studies that associated intracerebral rebleeding with hypertension were observational. At first the thought was that perhaps with the increase in blood volume in your brain you were getting an autonomic reflex making you more hypertensive. But studies such as the INTERACT study from Australia has shown that the higher the blood pressure the more likelihood that it causes rebleeding rather than being the result of rebleeding. And so aggressive management of hypertension acutely in the initial stages of the INTERACT study and in a smaller study called the ACCELERATE trial showed that if you rapidly and aggressively reduce blood pressure you can actually prevent hematoma expansion and hematoma volume is the number one predictor of outcome.

    卡梅洛教授：颅内出血与高血压的相关性最初是在观察性研究中被发现。早先认为颅内出血容积的增加通过植物神经反射使血压升高，但澳大利亚INTERACT等研究表明，血压越高、颅内再出血可能性越大，而不是再出血引起高血压。INTERACT试验初期及另一项小规模的ACCELERATE试验都表明，采取积极的降压策略快速有效地降低血压可预防血肿扩大，而血肿体积是预后的第一预测因子。

    <International Circulation>:Are there any special factors you need to pay attention to when you aggressively lower their blood pressure?   
   《 国际循环》：在积极降压的过程中，我们应注意哪些特殊因素？

    Prof Carmelo Graffagnino:  The issues which surface is understanding what levels you lower the blood pressure to and so if for example a person has a chronic existing history of hypertension and they come to you with a mean arterial pressure of a 120 or 130mm/Hg and if you drop it very dramatically say down to 60 or 70mm/Hg you may cause end organ problems because that patient’s brain was used to higher blood pressure. With somebody who has had no history of hypertension you can probably much more safely reduce it. One of the factors we look at is that if there is someone with pre-existing hypertension or if it is someone who has a new bleed for other reasons. Other factors which are important include volume of hematoma in their brain because if there is increasing intracerebral pressure and you reduce the systemic pressure too much theoretically you may reduce perfusion to the good brain. So you have to strike a balance  so the patient does not rebleed by lowering it with over lowering pressure causing organ failure and poor perfusion to the brain.
     卡梅洛教授：首先应该清楚要将患者血压降至什么水平。例如，1例既往有高血病史、就诊时平均动脉压120~130 mmHg的患者，如将其平均动脉压骤降到60~70 mmHg，可能会引起靶器官损伤，因为患者脑组织已适应较高的血压水平。对于没有高血压病史的患者，积极降压相对比较安全。因此我们需要关注的因素之一是患者既往有高血压病史、还是其他原因导致新发出血。其他重要因素还包括颅内血肿体积，因为颅内压升高理论上需要将血压降得更低，而这同时可能降低正常脑组织的血流灌注。我们必须在降低血压防止再出血和过度降压导致器官衰竭及脑灌注不足之间寻求平衡。