Sorry all, stepped away for a bit...yes, this setup is an armful of respiratory pieces that can fit together...so here's what they did to provide humidification for nasal cannula (starting at the oxygen outlet): hook up a high humidity nebulizer made to attach to wide bore tubing, which goes to a mask or trach mask for maximal humidity (these humidifiers have venturis on them as well to adjust FiO2)...then they attached another venturi (used on venturi masks) so now this venturi is actually attached "backwards" in the system...THEN they attached the nasal cannula to the nipple...given the use of the venturi used as a connector, I doubt much oxygen made it to the patient.
I have actually seen this very setup in a paramedic text (possibly written by the ICU nurse who set this setup up). This picture was posted by a RT colleague in some hospital in the US.
The message I wanted to convey is "just because its in a text, it ain't necesarily correct".