The machine's internal vacuum pump forces air out of the system, creating negative pressure.Creating Suction: Because the air pressure inside the device drops lower than the atmospheric pressure, it creates a powerful "pulling" force at the tip of the attached tubing.Transporting Fluids: When a medical professional or caregiver inserts the suction catheter (or Yankauer tip) into the patient's mouth, throat, or wound, the vacuum immediately draws out unwanted fluids and debris.