We constructed an on-line data management system and linked it to the communication protocol of a portable blood analyzer (i-STAT) in each operating room of our institution. We developed a new program that integrates circulatory dynamics data from a monitor with laboratory data from the i-STAT. Our new program permits the results to be viewed through an intranet using a novel prototype communication device for the i-STAT 300F. We verified that this system can improve the quality of patient care both bedside and in the monitoring room and compared the costs of blood testing using a conventional desktop blood-gas analyzer and using the i-STAT. We found that the novel integration of circulatory dynamics with laboratory data enhanced the quality of intraoperative patient monitoring and reduced the cost and work load of doctors working in the operating room.