For the liner, add the recommended water amount to bring the pressure cooker to pressure. This will vary but it's usually 1 cup of 1 1/2 cups.
Put a trivet into the pressure cooker liner and place the pan over the trivet.
Seal the lid and set the valve to sealing. Turn to "manual" or "pressure cook" for 25 minutes. Once the cycle is done, let it have a 10-minute natural release before switching the valve to have a quick pressure release.
Add the ketchup and mustard on top of the meatloaf and mix together on top.
Take the springform pan out of the pressure cooker and put it on a baking sheet.
Turn the oven to broil and put the pan under the broiler for about 6 minutes of time.