Many of our cleansing rituals you will not be allowed to perform in a hospital - they require smoke or smudging, aspering, salt, etc - not usually looked upon kindly lol

However, you can also have some success with hanging some herbs...You can use Bittersweet (Nightshade) if you can find it in Australia, you may be able to get it online through a tea merchant. Hanging it in secret in the room will be most effective.
Adding camphor to some water in a bowl and placing it in the room will also help cleanse the space of strongest energies form past visitors.

If you can get away with it, you can spray some consecrated water around the room (aspering) but use your common sense with this one don't want to cause any accidents! lol

A basil plant will bring love, good fortune and protection to the space.

Green Tourmaline will also offer a strong protective influence.

Personally for you, calcite and hematite would be beneficial.

HTH