Suction

In a medical context, suction refers to the mechanical removal of secretions, fluid, blood, or foreign material from the airway using a device that applies negative pressure through a plastic catheter or tube. It is a routine procedure in critical care, anaesthesia, and emergency medicine.

Suction is used to clear the nose, mouth, throat, or endotracheal tube when a patient cannot clear their own secretions effectively. This may be because they are unconscious, sedated, or have an impaired cough reflex. In cardiac arrest survivors on mechanical ventilation in critical care, tracheal suction is performed regularly to prevent secretions from blocking the airway or causing ventilator-associated pneumonia.

For conscious patients, suction can be uncomfortable and can stimulate coughing, retching, or (rarely) vagal reactions causing a drop in heart rate. In ventilated patients, it may briefly reduce oxygen levels, so supplemental oxygen is often given before the procedure. The duration and frequency of suctioning is carefully managed to minimise these effects.

Suction equipment is present on resuscitation trolleys and in ambulances for use during active resuscitation, where clearing the airway of vomit or blood is essential before effective ventilation can be established. See also: Endotracheal Intubation, Critical Care Team.