<snipped by me> I apologize I'm so late to the game on the hospitalization/injury issue, but I wanted to add a few things from a Trauma level, orthopedic level, and surgery level...as an RN.
- Weight loss and dehydration - the weight wasn't lost overnight and would not be gained back in a few days of hospitalization. Being home (or somewhere safe), resting, being offered food she likes will help her regain the weight. Labs would reveal hydration status (via electrolyte panels and renal panels) and fluids can be bolused in the ED. A dangerous electrolyte imbalance would most likely cause an overnight stay for observation as electrolytes are replaced. Mild imbalances can be replaced in the ED.
- Battery - as long as testing (Sono, CT, MRI, etc) reveal no internal injuries and no RISKS of internal or extremity injuries (think, for examples: fractured rib risking puncturing of lung; bone fracture risking blood vessels; swelling risking nerve damage or blood supply, etc) you will be discharged home. It takes time for tissue to heal, fluid from swelling to reabsorb, and old blood from bruising to reabsorb, and a person won't look too much better just from a short hospital stay. Home, elevation, ice, and NSAIDs will help those injuries.
- Broken noses, jaws, or other common fractures - often these are too swollen to do surgery right away. Sometimes surgery is delayed a week to 10 days to allow swelling to disperse. If the swelling or injury risks the airway, you will be hospitalized. <snipped by me>