The diagnosis of acute appendicitis is more difficult than at other times, as the enlarged uterus renders it almost impossible to explore the right iliac region satisfactorily.
—J. Whitridge Williams (1903)
These words summarize that during normal pregnancy, the gastrointestinal tract and its appendages undergo remarkable anatomical, physiological, and functional alterations. These changes, which are discussed in detail in Chapter 4 (Gastrointestinal Tract), can appreciably alter clinical findings normally relied on for diagnosis and treatment of gastrointestinal disorders such as appendicitis. Moreover, as pregnancy progresses, gastrointestinal symptoms become more difficult to assess. Physical findings are often obscured by a large uterus that displaces abdominal organs and can alter the location and intensity of pain and tenderness.
Fiberoptic endoscopic instruments have revolutionized diagnosis and management of most gastrointestinal conditions, and these are particularly well suited for pregnancy. Endoscopy in pregnancy is associated with a slightly increased risk for preterm birth, but this is likely due to the disease itself (Ludvigsson, 2017). With endoscopy, the esophagus, stomach, duodenum, and colon can be inspected (Cappell, 2011; Savas, 2014). The proximal jejunum can also be studied, and the ampulla of Vater cannulated to perform endoscopic retrograde cholangiopancreatography—ERCP (Akcakaya, 2014; Fogel, 2014). Preliminary data suggest that postendoscopic pancreatitis following gallstone removal may have a higher incidence in pregnant women (Inamdar, 2016). Experience in pregnancy with videocapsule endoscopy for small-bowel evaluation remains limited (Storch, 2006).
Upper gastrointestinal endoscopy is used for management as well as diagnosis of several problems. Common bile duct exploration and drainage are used for choledocholithiasis as described in Chapter 55 (Pancreatic Disorders). It is also used for sclerotherapy and for placement of percutaneous endoscopic gastrostomy (PEG) tubes. Several concise reviews have been provided (Cappell, 2011; Fogel, 2014; Gilinsky, 2006).
For visualization of the large bowel, flexible sigmoidoscopy can be used safely in pregnant women (Siddiqui, 2006). Colonoscopy is indispensible for viewing the entire colon and distal ileum to aid diagnosis and management of several bowel disorders. Except for the midtrimester, reports of colonoscopy during pregnancy are limited, but most results indicate that it should be performed if indicated (Cappell, 2010, 2011; De Lima, 2015). Bowel preparation is completed using polyethylene glycol electrolyte or sodium phosphate solutions. With these, serious maternal dehydration that may cause diminished uteroplacental perfusion should be avoided.
Noninvasive Imaging Techniques
The obvious ideal technique for gastrointestinal evaluation during pregnancy is abdominal sonography. Because computed tomography (CT) use is limited in pregnancy due to radiation exposure, magnetic resonance (MR) imaging is now commonly used to evaluate the abdomen and retroperitoneal space (Khandelwal, 2013). One example is magnetic resonance cholangiopancreatography—MRCP ...