INTRAOPERATIVE DATA-ACQUISITION FOR THE STUDY OF CEREBRAL-DYSFUNCTIONFOLLOWING CARDIOPULMONARY BYPASS

As a first step in our study to document postoperative cerebral dysfun ction, and to determine whether global cerebral blood flow can be impl icated in the etiology of this postoperative change, we have assembled a flexible data acquisition system to acquire and record data from fo ur independent sources, three in digital form and one analog. Each of the monitors that we use has a different requirement: One has eight ch annels of analog output; the other three have RS-232 digital outputs, each with a data stream with different characteristics. The central el ement of our data collection is a personal computer running the data a cquisition and analysis program, Lab VIEW for Windows (National Instru ments, Austin, TX). All data are processed through separate Lab VIEW g lobal variables; the data strings are concatenated and stored on the h ard disk in a spreadsheet format for further analysis. We illustrate a n intraoperative recording made during cardiopulmonary bypass (CPB) by showing a graph of the mean arterial pressure (MAP), mixed venous oxy hemoglobin saturation recorded from the jugular bulb (JVO(2)Sat), and temperature measured from the nasopharynx. A decrease in the MAP after unclamping the aorta is accompanied by a decrease in JVO(2)Sat.