Intestinal obstruction during pregnancy

Abstract

This is a review of literature concerning intestinal obstruction in pregnant women. Approximately 50-90% and 30% of pregnant women, respectively, suffer from nausea and vomiting, mostly during the first trimester. There is also increased risk of constipation. During the perioperative period, the administration of tocolytics should be considered only in women showing symptoms of a threatening premature delivery. Intensive hydration should be ordered to sustain uterine blood flow. The incidence of intestinal obstruction during pregnancy is estimated at 1:1500-1:66431 pregnancies and is diagnosed in II and III trimester in most cases. However, it can also occur in the I trimester (6%) or puerperium. Symptoms of intestinal obstruction in pregnancy include: abdominal pains (98%), vomiting (82%), constipation (30%). Abdominal tenderness on palpation is found in 71% and abnormal peristalsis in 55% of cases. The most common imaging examination in the diagnosis of intestinal obstruction is the abdominal X-ray. However, ionizing radiation may have a harmful effect on the fetus, especially during the first trimester. X-ray is positive for intestinal obstruction in 82% of pregnant women. Ultrasonography and magnetic resonance imaging are considered safe and applicable during pregnancy. Intestinal obstruction in pregnant women is mostly caused by: adhesions (54.6%), intestinal torsion (25%), colorectal carcinoma (3.7%), hernia (1.4%), appendicitis (0.5%) and others (10%). Adhesive obstruction occurs more frequently in advanced pregnancy (6% - I trimester, 28% - II trimester, 45% - III trimester, 21% - puerperium). Treatment should begin with conservative procedures. Surgical treatment may be necessary in cases where the pain turns from recurrent into continuous, with tachycardia, pyrexia and a positive Blumberg sign. If symptoms of fetal anoxia are observed, a C-section should be carried out before surgical intervention. The extent of surgical intervention depends on the intraoperative evaluation. Intestinal torsion during pregnancy mostly occurs in the sigmoid colon and cecum. Small bowel torsion secondary to adhesions is diagnosed in 42% of pregnant women with intestinal obstruction. The risk of intestinal torsion is higher in the 16-20 and 32-36 weeks of pregnancy and during puerperium. Intestinal torsion results in vessel occlusion which induces more severe symptoms and makes urgent surgical intervention necessary. The overall prognosis is poor – during II and III trimester the fetal mortality rate reaches 36% and 64%, respectively, while the risk of maternal death is 6%. Acute intestinal pseudoobstruction can be diagnosed during puerperium, especially following a C-section. Diagnosis is made on the basis of radiological confirmation of colon distension at the cecum as >9cm, lack of air in the sigmoid colon and rectum, exclusion of mechanical obstruction. In most cases, the treatment is based on easing intestine gas evacuation and administering neostigmine. The authors point out the need for multi-specialty cooperation in the diagnostic-therapeutic process of pregnant women suspected with intestinal obstruction, since any delay in making a correct diagnosis increases the risk of severe complications, both for the woman and the fetus.