🫁 Mechanical Ventilation Explained We say normal breathing causes negative pressure when the diaphragm contracts. Think of pulling the air in! With mechanical ventilation we push the air in with the ventilator. This is positive pressure! Mechanical ventilation is used for surgery, pneumonia, ARDS, COPD, asthma, and loss of respiratory drive. The ventilator breathes for the patient while they can’t do it on their own! Ventilators provide different amounts of support depending on the settings. Ha