“Because it is narrow, the human intestine can become obstructed relatively easily, making such blockages a common cause for admission to a surgical ward. In patients with small bowel obstructions, the portion of the intestine proximal to the obstruction swells. As the swelling increases, the blood supply to that part of the gut is compromised, and if the obstruction is not relieved, that part of the bowel will die. This leads to perforation and infection of the abdominal cavity, or peritoneal cavity, as doctors call it. This inflammation or infection of the peritoneum is called peritonitis. The inflammation leads to fluid being drawn out of the blood vessels and accumulating in the peritoneal cavity; this in turn can cause the blood pressure to fall. Unchecked and untreated, a bowel obstruction usually results in death.”