Credit: Ron Tom/Getty Images Photo: Alex Karev and Dr. April Kepner

Drew, the post-op kid whose case Stark assigned to Meredith and Alex, developed a perforated ulcer. So first thing's first: what is an ulcer? Simply put, it's a sore that develops in the lining of the stomach or in the duodenum — the first part of the intestine — as a result of an imbalance of digestive fluids between the two parts. They can cause the bearer pain, bloating, heartburn, nausea, and even worse symptoms.

When an ulcer is perforated, it has effectively burned through the wall of the stomach, which means digestive fluids can leak into the abdominal cavity. The only treatment is emergency surgery, which is why Meredith and Alex couldn't wait until the morning for Stark to return to the hospital. Drew's ulcer was a result of his chest-wall surgery, but you can take action to help prevent ulcers of your own: don't smoke, drink alcohol sensibly, and use aspirin only when necessary.

Source: WebMD

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