A 32-year-old G2P1001 at 20 weeks gestational age presents to the emergency room complaining of constipation and abdominal pain for the past 24 h. The patient also admits to bouts of nausea and emesis since eating a very spicy meal at a new Thai restaurant the evening before. She denies a history of any medical problems. During her last pregnancy, the patient underwent an elective cesarean section at term to deliver a fetus in the breech presentation. The emergency room doctor who examines her pages you and reports that the patient has a low-grade fever of 100degF, with a normal pulse and blood pressure. She is minimally tender to deep palpation with hypoactive bowel sounds. She has no rebound tenderness. The patient has a WBC of 13,000, and electrolytes are normal. What is the appropriate next step in the management of this patient?

This patient's history and physical exam are consistent with an intestinal obstruction. An intestinal obstruction must be ruled out because, if it goes undiagnosed and untreated, it can result in a bowel perforation. This patient has a history of a previous abdominal surgery, which places her at risk for adhesions. Beginning in the second trimester, the gravid uterus can push on these adhesions and result in a bowel strangulation. Common symptoms of intestinal obstruction include colicky abdominal pain, nausea, and emesis. Signs of a bowel obstruction include abdominal tenderness and decreased bowel sounds. Fever and an elevated white blood cell count are present with bowel strangulation and necrosis. This patient has a mild leukocytosis, which is also characteristic of normal pregnancy. In order to rule out an intestinal obstruction, an upright or lateral decubitus abdominal x-ray should be done to identify the presence of distended loops of bowel and air-fluid levels, which confirm the diagnosis. Treatment consists of bowel rest, intravenous hydration, and nasogastric suction; patients who do not respond to conservative therapy may require surgery. Bowel stimulants such as laxatives or enemas should not be administered. Pregnant women are predisposed to constipation secondary to decreased bowel motility induced by elevated levels of progesterone. The symptoms of nausea and emesis in this patient and the presence of a low-grade fever prompt further workup because her presentation is not consistent with uncomplicated constipation. In pregnancy, constipation can be treated with hydration, increased fiber in the diet, and the use of stool softeners. The patient's sudden onset of emesis and abdominal pain is not consistent with the normal presentation of hyperemesis gravidarum. Hyperemesis typically has an onset in the early part of the first trimester and usually resolves by 16 weeks. It is characterized by intractable vomiting causing severe weight loss, dehydration, and electrolyte imbalance. The ingestion of spicy foods during pregnancy can cause or exacerbate gastric reflux or "heartburn" but would not cause the severity of the symptoms described in this patient's presentation. Dyspepsia during pregnancy can be treated with antacids. The patient with gastric reflux in pregnancy should also be counseled to eat smaller, more frequent meals and bland food.