Aspiration pneumonia

Abstract

Pulmonary aspiration of stomach contents is a common clinical problem. Symptoms and consequences depend on the aspired volume, the pH and the content of food particles and bacteria. There are two phases following an aspiration of stomach contents into the lungs. The first phase is nonspecific and begins a few minutes after the aspiration. This phase is due to the chemical injury. The second phase is an inflammatory reaction. The reaction is haemorrhagic, granulocytic and necrotizing when the aspirate is acid (pH < 2.5). The presence of food particles causes granulomas. The immunological reactions are biphasic as well. The bacterial infection is mainly secondary to the chemical inflammation and occurs with an infection rate of 25-50%. The optimum management is symptomatic and should entail immediate endotracheal suction, aggressive ventilatory support with supplemental oxygen, CPAP or PEEP if indicated by clinical assessment and blood gas measurements, adequate fluid replacement and antibiotics if there is evidence of bacterial infection.