What are the problems associated with aspiration?

What are the problems associated with aspiration?

Aspiration during general anesthesia is very rare with estimates ranging from 1:4,000 to 1:9,000. However, when it does occur it is a serious problem. Aspiration of large gastric particles can completely obstruct the airway any-where along the tracheo-bronchial tree making ventilation difficult or impossible. Furthermore, a chemical pneu-monitis resulting from aspiration of gastric contents, known as Mendelson’s syndrome, can occur. This syn-drome may occur if the gastric aspirate has a pH <2.5 and a volume >0.4 ml/kg or 25 cc in the adult.