Most cases of intestinal obstruction during pregnancy result from pressure of the growing uterus on intestinal adhesions. According to Davis and Bohon (1983), this more likely occurs around midpregnancy when the uterus becomes an abdominal organ; in the third trimester when the fetal head descends; or immediately postpartum when uterine size acutely shrinks. Perdue (1992) reported that 98 percent of afected pregnant women had either continuous or colicky abdominal pain, and 80 percent had nausea and vomiting. Abdominal tenderness was found in 70 percent, and abnormal bowel sounds noted in only 55 percent. Plain abdominal radiographs following soluble contrast showed evidence of obstruction in 90 percent of women (Fig. 54-3). Plain radiographs, however, are less accurate for diagnosing small-bowel obstruction, and we and others have found that CT and MR imaging can be diagnostic (Biswas, 2006; Essilie, 2007; McKenna, 2007). Colonoscopy can be both diagnostic and therapeutic for colonic volvulus (Dray, 2012; Khan, 2012).
During pregnancy, mortality rates with obstruction can be excessive because of diicult and thus delayed diagnosis, reluctance to operate during pregnancy, and the need for emergency surgery (Firstenberg, 1998; Shui, 2011). In an older report of 66 pregnancies, Perdue and associates (1992) described a 6-percent maternal mortality rate and 26-percent fetal mortality rate. Two of the four women who died were in late pregnancy, and they had bowel perforation from sigmoid or cecal volvulus caused by adhesions.
Also known as Ogilvie syndrome, pseudo-obstruction is caused by adynamic colonic ileus. It is characterized by massive abdominal distention with cecal and right-hemicolon dilatation. Approximately 10 percent of all cases are associated with pregnancy, and its frequency has been reported as high as 1 in 1500 deliveries (Reeves, 2015). he syndrome usually develops postpartum-most commonly after cesarean delivery-but it has been reported antepartum (Tung, 2008). Rarely, the large bowel may rupture (Singh, 2005). Treatment with an intravenous infusion of neostigmine, 2 mg, usually results in prompt decompression (Song, 2015). In some cases, colonoscopic decompression is performed, and laparotomy is needed for perforation (De Giorgio, 2009; Rawlings, 2010).
The lifetime incidence for appendicitis ranges from 7 to 10 percent (Flum, 2015). hus, it is not surprising that an evaluation for possible appendicitis is relatively common during pregnancy. heilen and colleagues (2015) studied 171 such women during a 5-year period, but only 12 women ultimately were found to have pathologically confirmed appendicitis. After clinical and imaging evaluation, the frequency of suspected appendicitis is much lower and that of confirmed appendicitis in more than 8 million women ranged from 1 in 1000 to 1 in 5500 births (Abbasi, 2014; Hee, 1999; Mazze, 1991).