This effective first-aid technique to resuscitate choking and drowning victims was introduced by Dr. Henry J. Heimlich (1920–) of Xavier University in Cincinnati, Ohio. It is a technique for removing a foreign body from the trachea or pharynx where it is preventing flow of air to the lungs. When the victim is in the vertical position, the maneuver consists of applying subdiaphragmatic pressure by wrapping one’s arms around the victim’s waist from behind, making a fist with one hand and placing it against the victim’s abdomen between the navel and the rib cage, clasping one’s fist with the other hand, and pressing in with a quick, forceful thrust. Repeat several times if necessary. When the victim is in the horizontal position (which some experts recommend), the rescuer straddles the victim’s thighs.