International Circulation: Do you know what this procedure has not been implemented up until now?
　Dr. Brar: Contrast nephropathy has been around 30 years and we have tried many things. The one effective procedure we keep coming back to is hydration. The challenge is to know for how much and for how long. Those two variables are critical and in some ways very obvious. We have tried many creative procedures but this trials represents a getting back to the basics. It has likely been staring at us for the past decade. I was reading patients based upon their volume status and what they would need， we do that in so many other settings in the hospital: the coronary care unit， the intensive care unit， with other catheters. It is a bit peculiar that in the cathlab were we have so much hemodynamic information at our disposal， we do not avail ourselves of that information.
《国际循环》：为何这种方案至今未能广泛应用？
Dr. Somjot Brar：有关对比剂肾病的讨论已持续30年，我们尝试了各种方法。我们一直沿用的有效手段就是水化。而明确水化的量和持续时间是我们一直面临的挑战，这两个指标至关重要且非常明显。我们尝试了许多创新性的方法，但本试验表明，我们应回到最基础的手段，它好像在过去10年中一直在注视着我们。我们根据患者的输液状态及其需要量进行回顾，实际上我们在医院内的其他许多科室都做过同样的工作：冠状动脉监护室、重症监护室、及其他导管室。这种现象的确有些奇怪：在导管室我们获得了如此多的血流动力学信息，却没有很好的利用。
International Circulation: How was the renal function of the patients in this trial?
Dr. Brar: To be admitted to the trial， the study required a GFR of less than 60. This places at patients CKD Stage III and so they have at least moderate impairment of kidney function. In addition to that， we required one addition risk factor in contrast nephropathy. That was either the patient had diabetes， age greater than 75， hypertension， or history of heart failure. Based on the combination of those criteria， the patients would be deemed at moderate to high risk for contrast nephropathy.
《国际循环》：这些试验中患者的肾功能如何？
Dr. Somjot Brar：这项试验的设计需要患者的GFR≤60，这意味着患者为CKD III期，其至少为中度肾功能受损。此外，我们还要求患者具有对比剂肾病的至少一项危险因素：糖尿病、年龄>75岁、高血压、心力衰竭病史中的一项。基于这些联合标准，入选者是发生对比剂肾病的中-高危患者。