Pathophysiologic and Psychological Considerations
Abnormalities of the GI tract are numerous and represent every type of major pathology that can affect other organ systems, in-cluding bleeding, perforation, obstruction, inflammation, and cancer. Congenital, inflammatory, infectious, traumatic, and neoplastic lesions have been encountered in every portion, and at every site, along the length of the GI tract. As with all other organ systems, the GI tract is subject to circulatory disturbances, faulty nervous system control, and aging.
Apart from the many organic diseases to which the GI tract is susceptible, there are many extrinsic factors that can interfere with its normal function and produce symptoms. Stress and anxiety, for example, often find their chief expression in indigestion, anorexia, or motor disturbances of the intestines, sometimes pro-ducing constipation or diarrhea. In addition to the state of men-tal health, physical factors such as fatigue and an inadequate or abruptly changed dietary intake can markedly affect the GI tract. When assessing and instructing the patient, the nurse should con-sider the variety of mental and physical factors that affect the func-tion of the GI tract.
Normal physiologic changes of the GI system that occur with aging are identified in the accompanying Gerontologic Consid-erations box. The nurse should carefully assess and monitor signs and symptoms related to these changes. Age-related changes in the mouth include loss of teeth, diminished number of taste buds, decreased production of saliva, and atrophy of gingival tissue. These changes cause difficulty in chewing and swallowing. Changes in the esophagus include decreased muscle tone and weakness in the lower esophageal sphincter, leading to reflux and heartburn.
Decreased gastric motility leads to delayed gastric emptying. Atrophy of the mucosa causes a decrease in HCl production, and this can lead to food intolerances, malabsorption, or decrease in vitamin B12 absorption. Changes in the small and large intestine are evidenced largely by decreased motility and decreased transit time, which lead to complaints of indigestion and constipation. Other changes lead to decreased absorption of nutrients (dextrose, fats, calcium, and iron) in the large intestine. The nerve supply to the anal sphincter is sometimes impaired, causing fecal incon-tinence (Luekenotte, 2000).