Heat penetration in locally applied hyperthermia in the abdomen during intra-operative hyperthermic intraperitoneal...

Hyperthermic intraperitoneal chemotherapy (HIPEC) with mitomycin C has been applied following cytoreductive surgery for various peritoneal surface malignancies. The aim of this study was to evaluate heat penetration in the abdomen during 10 HIPEC procedures.

Temperature measurements were taken at 5 levels through the abdominal wall. Core temperature and room temperature were also measured. The relationships between the temperature gradient and room or core temperature were studied.

At the start of perfusion, the temperature was estimated on average to be 40.6 degrees C at the first level, then it decreased by 1.7 degrees C (SD 1.0 degree C, p = 0.0001) in the first mm. In outward direction, it decreases by a further 1.5 degrees C per cm (SD 0.3 degree C/cm, p < 0.0001). The core temperature influenced the temperature gradient; the room temperature was not found to be a significant factor. At the end of perfusion, the temperature is estimated on average to be 40.1 degrees C at the first level, then it decreased by 0.8 degree C (SD 0.7 degree C, p = 0.011) in the first mm. In an outward direction, it decreased by a further 1.7 degrees C per cm (SD 0.4 degree C/cm, p = 0.0001). No evidence of an association between the temperature gradient and the room temperature or the core temperature was observed.

Hyperthermia used during HIPEC procedures has a limited penetration depth. The slope in temperature seems to be related to the core temperature.