Question

Sammy, age 3 years, ate his dinner and then said his tummy hurt. His mother suggested he lie down in the adjacent room while his parents finished dinner. A few minutes later, they heard Sammy vomiting. His mother rushed in to lift Sammy up. When vomiting ceased, they noticed Sammy continued to cough and seemed to be choking. He was struggling to breathe and a wheezing sound was obvious. It appeared that he had aspirated some vomitus. His parents drove him to a nearby hospital for examination.

Discuss the specific effects of aspirating vomitus on Sammy, including the probable effects on his bronchi and lungs. Why might one lung be affected more than the other?

Answer 1

The stomach contents are highly acidic due to the presence of gastric acid. The patient in the above scenario has high probability of developing aspiration pneumonia. The damage caused by the acidic contents is also called chemical pneumonitis.

This is caused by accidental passage of oral or gastric contents into the respiratory tract. The resulting damage occurs in 2 steps. Initially the acidic content has a direct toxic effect on the respiratory epithelium, that is the epithelial pinioning of bronchus and the branches further down. This can result in pulmonary interstitial edema . In the next phase, the body's immune system is activated and this leads to recruitment of macrophages, cytokines and neutrophil infiltration. These mechanisms produce free radicals which cause further damage to the lung tissues.

The right bronchus is wider and is oriented straighter in relation to main bronchus when compared to the left bronchus. Hence any foreign body has a higher chance of going into the right bronchus . This applies for aspiration pneumonia as well. The most frequently affected lobes are the right middle and lower lobes.