Techniques for monitoring fluid volumes during peritoneal analysis include: computing lower abdominal fluid volumes, continuously during a dwell time of a peritoneal dialysis treatment, based at least on bioimpedance data from electrodes positioned on a patient's upper thighs; and computing intraperitoneal volumes, continuously during the dwell time of the peritoneal dialysis treatment, based at least on bioimpedance data from the electrodes positioned on the patient's upper thighs and electrodes positioned on the patient's torso.