Thermal Safety of Forced-Air Warming During Balloon Occlusion in Isolated Perfusion Chemotherapy: A Prospective Feasibility Study Using Multisite Temperature Monitoring

Background: Isolated Perfusion Chemotherapy (IPC) with balloon occlusion creates transient ischemic tissue compartments while patients remain exposed to significant perioperative heat loss. Active warming during these phases is commonly avoided due to theoretical concerns regarding impaired heat distribution and potential local heat accumulation in ischemic tissue. This study investigated the thermal safety of forced-air warming during IPC under these conditions. Methods: In this prospective observational study, 31 patients undergoing IPC were monitored during balloon-induced vascular occlusion. Convective warming was applied using a forced-air system set to 43 °C. Core temperature was measured rectally, and local temperatures were continuously recorded at gluteal, lumbar, and interscapular sites. Temperature trajectories and maximum values during occlusion were analysed descriptively. Results: Local temperature increases during ischemia were limited, with a maximum increase of 2.3 °C at the lumbar site. Absolute temperatures remained well below the predefined safety threshold of 39.5 °C at all skin measurement sites (maximum observed 37.7 °C). Core temperature remained stable throughout the occlusion phase. No evidence of local heat accumulation, threshold exceedance, or thermal skin reactions was observed. Conclusions: Under conditions of controlled application, close temperature monitoring, and short ischemic intervals, forced-air warming during IPC did not result in local overheating or clinically relevant thermal exposure. These findings challenge the prevailing precautionary approach of avoiding active warming during vascular isolation and provide prospective clinical evidence supporting a reassessment of temperature management strategies toward actively maintained normothermia in isolated perfusion chemotherapy.