Put the trivet in the bottom of the Instant Pot and pour in 1 cup of water.
Shape the meat into a loaf and place in a dish that fits into the Instant Pot.
Put on the lid, set valve to seal, and pressure cook for 25 minutes with a quick pressure release.
When cooked, turn the Instant Pot off and let the meatloaf rest for about 10 minutes with the lid off before slicing.
Notes
Avoid dirtying extra dishes by putting in a dish that will fit in your Instant Pot or slow cooker before putting the meat in it -- try a stainless steel pan.