A blower unit for use as part of an integrated blower/humidification system is described. The blower unit has an outer casing, which encloses and forms part of the blower unit, the casing including an air inlet vent. The blower unit further includes a humidifier compartment for receiving a humidifier unit with a separate gases inlet and outlet, the compartment having a heater base for heating the contents of the humidifier unit. The compartment also has a blower inlet port which aligns with the humidifier unit inlet in use, the blower providing a gases path through the casing between the inlet vent and the inlet port. The blower unit also includes a fan for providing a pressurised gases stream along the gases path, and a power supply unit for powering the fan. The gases path is routed over the power supply unit in order to provide a cooling air flow.