Wound packing is particularly effective for controlling bleeding from deep wounds like gunshot or stab wounds or other penetrating injuries that prove difficult to control with only direct pressure.

When they come in contact with blood, they rapidly expand and pack the wound cavity in about 20 seconds, placing enough pressure to stop blood flow while the patient is being transported.

“A medic must pack gauze directly into the wound cavity, sometimes as deep as 5 inches into the body, to stop bleeding from an artery,” Popular Science explains.

Clinical radiological examinations of gunshot injuries often show the presence of gas cavities in the tissue along the bullet path which provide first information about the temporary wound cavity.

School staffers in Ferndale are undergoing training that officials say is absolutely necessary to keep students safe.

A greater diameter of the temporary wound cavity is associated with a larger volume of the temporary wound cavity, which increases the suction effect following the passage of the bullet.