Abstract: The invention concerns a fluid circulation and mixing system (100) for a cryocabin arrangement used in a whole-body cryotherapy treatment and a related cryocabin arrangement (120), including a system (100) and a cabin (101) for accommodating a patient. The fluid circulation system (100) includes appliances for effective mixing of cryogenic liquid with ambient air and/or for preventing the cryogenic liquid from settling down on the bottom of evaporator. The cryocabin arrangement (120) further includes appliances for generating and maintaining a fluidic whirl (vortex) within the patient cabin, thus enhancing an overall efficiency of the cryotherapy treatment in general and improving beneficial effects of each individual cryotherapy treatment session.