BIS offers a good possibility to monitor the water content of a person. This can be used in monitoring decompensated CHF patients. Since most patients with acute heart failure suffer not only from lung edema, but also from edema in limbs a combination of segmental and whole body BIS measurements offers the best options to supervise the course of diseases. In this paper, both BIS measurements show a strong correlation with the water balance and weight loss. Open access: No View