Superior mesenteric artery syndrome.

Superior mesenteric artery (SMA) syndrome is an uncommon and potentially fatal cause of small bowel obstruction where the third portion of the duodenum is compressed between the abdominal aorta and the superior mesenteric artery. This is most frequently seen after sudden and significant weight loss, but other etiologies can also cause this duodenal compression. This syndrome can lead to food aversion, poor intake, and weight loss that exacerbate symptoms in a vicious cycle. SMA syndrome is often a diagnosis of exclusion due to nonspecific symptoms, including abdominal pain and distention, feelings of fullness after meals, and bilious emesis. Diagnosis may be assisted with radiography, tomography, endoscopy, and ultrasound imaging. Once SMA syndrome is identified, treatment is directed toward symptom management and nutritional support. If conservative measures fail, symptoms are severe, or the duodenum is compromised, several effective surgical procedures are routinely considered. This article provides an overview of SMA syndrome including history, pathophysiology, signs and symptoms, diagnostic testing, medical and surgical treatment, and implications for nursing staff.