The Design of an Automatic Temperature Compensation System through Smart Heat Comparison/Judgment and Control for Stable Thermal Treatment in Hyperthermic Intraperitoneal Chemotherapy (HIPEC) Surgery.

After surgery for ovarian cancer or colorectal cancer, residual tumors are left around. A practical way to treat residual tumors is to destroy them with heat by injecting high-temperature drugs into the abdominal cavity. The injected medicinal substances are induced to flow out of the abdominal cavity; then, the spilled drug flows back into the abdominal cavity through feedback. During this process, the heat starts to decrease; thus, the treatment performance reduces. To overcome this problem, this study compares and assesses the temperature needed to maintain the heat for treatment and transmits a command signal to the heat exchanger through a look-up table (LUT). When the temperature decreases during the circulation of medications leaking out of the abdominal cavity, the LUT transmits a control signal ( T p ) to the heat exchanger, which increases or vice versa. However, if the temperature ( T o ) is within the treatment range, the LUT sends a T s signal to the heat exchanger. This principle generates a pulse signal for the temperature difference ( T dif ) in TC by comparing and determining the temperature ( T o ) of the substance flowing out of the abdominal cavity with the reference temperature ( T ref ) through the temperature comparator (TC). At this time, if the signal is 41 °C or less, the LUT generates (heats) a T p signal so that the temperature of the heat exchanger can be maintained in the range of 41 °C to 43 °C. If the T dif is 44 °C or higher, the LUT generates (cools) the T a signal and maintains the temperature of the heat exchanger at 41-43 °C. If the T dif is maintained at 41-43 °C, the LUT generates a T x signal to stop the system performance. At this time, the TC operation performance and T dif generation process for comparing and determining the signal of T o and T ref for drugs leaking out of the abdominal cavity is very important. It was observed that the faster the response signal, the lower the comparison and judgment error was; therefore, the response signal was confirmed to be 0.209 μs. The proposed method can guarantee rapid/accurate/safe treatment and automatically induce temperature adjustment; thus, it could be applied to the field of surgery.