Medical device system

A medical device system comprising:

• first and second medical devices, each of which is used in a body cavity and surfaces of which have conductivity;
• a first electrode electrically connected to the surface of the first medical device;
• a second electrode electrically connected to the surface of the second medical device;
• a human body electrode plate that can come into contact with a surface of a human body outside of a body cavity;
• a human body electrode electrically connected to the human body electrode plate;
• a resistance measuring unit for measuring an inter-device electric resistance value as electric resistance between the first electrode and the second electrode and an electrode-to-human body resistance value as electric resistance between the first electrode or the second electrode and the human body electrode;
• a determining unit for determining, when an electric resistance value ratio as a ratio of the inter-device electric resistance value and the electrode-to-human body resistance value decreases, that the first medical device and the second medical device have come into contact with each other;
• and
• a warning generating unit for generating a warning when the determining unit determines that the first medical device and the second medical device have come into contact with each other.