256 to the crystalloid mixing junction 280 the crystalloid control pump 286 moves crystalloid solution at a relatively high concentration from the second source of crystalloid solution 276 to the crystalloid mixing junction 280 where a blended crystalloid solution is produced the blended crystalloid solution is conveyed through the blended crystalloid tubing 260 by the action of the crystalloid pump 258 driven by the crystalloid pump motor 259 and delivered to the cardioplegia blending junction 262 where it is blended with the diverted arterial blood from the cardioplegia mixture mixing junction 262 the cardioplegia mixture comprising the diverted arterial blood and the blended crystalloid solution is delivered through the cardioplegia tubing 264 to the patient 39 s heart 14 the total rate volume of cardioplegia solution delivered to the heart 14 can be set by the perfusionist or a control device 251 by adjusting the speed of the pump motor 254 and cardioplegia pump 252 to adjust the amount of diverted arterial blood delivered into the cardioplegia mixture and by adjusting the speed of the crystalloid pump 258 and crystalloid pump motor 259 to control the total amount of blended crystalloid delivered to the mixing junction 262 the total flow of cardioplegia mixture to the heart 14 will be the sum of the diverted arterial blood flow and the flow of blended crystalloid solution the dilution factor of the cardioplegia mixture will be determined by the ratio of the speeds and therefore the flow rates of the crystalloid pump 258 and cardioplegia pump 252 to adjust the concentration of crystalloid in the.