What substance is typically expelled from the body postmortem due to pressure?

The substance that is typically expelled from the body postmortem due to pressure is purge. During the process of decomposition, gases produced by bacteria in the body can build up, creating internal pressure. This pressure can lead to the expulsion of fluids and semi-solid substances from the body, particularly from the mouth and nose. This phenomenon is commonly referred to as purging or purge fluid.

Purge fluid is a combination of bodily fluids and gases, and it may also contain partially decomposed organic material. Understanding this process is crucial for mortuary science professionals as they prepare the deceased for viewing or burial. It indicates the changes that occur in the body after death and helps in managing the physical appearances of the deceased during the preparation.

Other substances like blood, gas, and feces can also undergo changes or be affected postmortem, but they do not typically associate with the specific expulsion caused by pressure as significantly as purge fluid does.