微控制器控制低温系统.pdfVIP

C Journal of Medical Systems, Vol. 29, No. 5, October 2005 ( 2005) DOI: 10.1007/s10916-005-6101-9 A New Microcontroller Supervised Thermoelectric Renal Hypothermia System Hakan Is¸ik1 In the present study, a thermoelectric system controlled by a microcontroller is devel- oped to induce renal hypothermia. Temperature value was managed by 8-byte micro- controller, PIC16F877, and was programmed using microcontroller MPASM pack- age. In order to ensure hypothermia in the kidney 1–4 modules and sensors perceiving temperature of the area can be selected. Temperature values are arranged proportion- ately for the selected area and the determined temperature values can be monitored from an Liquid Crystal Display (LCD) screen. The temperature range of the system is between −50 and +50◦ C. Renal hypothermia system was tried under in vivo condi- tions on the kidney of a dog. KEY WORDS: renal hypothermia; microcontroller; thermoelectric module. INTRODUCTION Recent studies about renal surgery are in search of a bloodless and long-lasting method that does not cause renal dysfunction. This can be achieved by working in a hypothermic setting. In a hypothermic setting, cells slow down their metabolism by consuming less energy and oxygen. Thus, the cells are protected and resume their functions after ischemia. The most important issues in long-lasting parenchymatous renal surgery are to provide an operation medium free of blood and to prevent renal dysfunction in the postoperative period. The method most easily used for this purpose is clamping the renal artery. The disadvantage of the concerned method is that it is limited to a period of 30 min in order to avoid loss of function in the kidney. It was found that warm ischemia for over 30 min leads to renal dysfunction.(1)