Constipation is the slow movement of feces through the large intestine that results in the passage of dry, hard stool. This can result in discomfort or pain. The longer the transit time of stool in the large intestine, the greater the fluid absorption and the drier and harder the stool becomes.
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Inactivity, immobility, or physical and social impediments (particularly inconvenient bathroom availability) can contribute to constipation. Depression and anxiety caused by cancer treatment or cancer pain can lead to constipation. Perhaps the most common causes of constipation are inadequate fluid intake and pain medications; however, these causes are manageable.
Constipation may be annoying and uncomfortable, but fecal impaction can be life-threatening. Impaction refers to the accumulation of dry, hardened feces in the rectum or colon. The patient with a fecal impaction may present with circulatory, cardiac, or respiratory symptoms rather than with gastrointestinal symptoms. If the fecal impaction is not recognized, the signs and symptoms may progress and result in death.
In contrast to constipation or impaction, an intestinal obstruction is a partial or complete occlusion of the bowel lumen by a process other than fecal impaction. Intestinal obstructions can be classified by the following three means:
The type of obstruction.
The obstructing mechanism.
The part of the bowel involved.
Structural disorders, such as intraluminal and extraluminal bowel lesions caused by primary or metastatic tumor, postoperative adhesions, volvulus of the bowel, or incarcerated hernia, affect peristalsis and the maintenance of normal bowel function. These disorders can lead to total or partial obstruction of the bowel. Patients who have colostomies are at special risk of developing constipation. If stool is not passed on a regular basis (once a day to several times a day), further investigation is warranted. A partial or complete blockage may have occurred, particularly if no flatus has been passed.
Diarrhea can occur throughout the continuum of cancer care, and the effects can be physically and emotionally devastating. Although less prevalent than constipation, diarrhea remains a significant symptom burden for people with cancer. Diarrhea can do the following: