During residency we admitted almost all altered mental status patients without an etiology especially the elderly. If you have a patient brought in by the family confused but not lethargic, afebrile, other vitals are stable, head CT, CXR, urine, ekg, basic labs are normal, and you find no focal neurological deficits is it still necessary to admit? If you do admit do you tell the hospitalist "it might be a subtle cva and he/she needs an mri and further work-up or maybe early sepsis and I'll order blood cultures etc.." or do you just say "Im admitting someone for AMS, don't have a definite cause here in the ED, please take the pt."