I'm hospitalized for kidney infection, and on oxygen as blood saturation is around 80, normally 97-99. could my infection or complications cause this?

Sounds like: Severe vitamin b1 deficiency. This vitamin has an important part in picking up oxygen from the lung and delivering it to the tissues. Ask for a venous oxygen level and if it is high, it means that oxidation (use of oxygen by the tissues) is also poor and is characteristic of b1 def.

Additional Concern: Are you sure about the diagnosis of a kidney infection. Pulmonary renal syndromes; wegener's gn, goodpastures, cause pulmonary hemorrhage (bleeding) and present with lung disease and kidney failure. Also, 10-20 % of patients with kidney infections seed the blood stream with bacteria and you can develop infections outside of the kidney. Finally, ards, a lung disease can develop in very ill pts.