Diarrhea - Abnormalities of Fecal Elimination

DIARRHEA

Diarrhea is increased frequency of bowel movements (more than three per day), increased amount of stool (more than 200 g per day), and altered consistency (ie, looseness) of stool. It is usually associated with urgency, perianal discomfort, incontinence, or a combination of these factors. Any condition that causes increased intestinal secretions, decreased mucosal absorption, or altered motility can produce diarrhea. Irritable bowel syndrome (IBS), inflammatory bowel disease (IBD), and lactose intolerance are frequently the underlying disease processes that cause diarrhea (Stone et al., 1999).

Diarrhea can be acute or chronic. Acute diarrhea is most often associated with infection and is usually self-limiting; chronic diarrhea persists for a longer period and may return sporadically. Diar-rhea can be caused by certain medications (eg, thyroid hormone re-placement, stool softeners and laxatives, antibiotics, chemotherapy, antacids), certain tube feeding formulas, metabolic and endocrine disorders (eg, diabetes, Addison’s disease, thyrotoxicosis), and viral or bacterial infectious processes (eg, dysentery, shigellosis, food poi-soning). Other disease processes associated with diarrhea are nutri-tional and malabsorptive disorders (eg, celiac disease), anal sphincter defect, Zollinger-Ellison syndrome, paralytic ileus, intestinal ob-struction, and acquired immunodeficiency syndrome (AIDS).

Pathophysiology

Types of diarrhea include secretory, osmotic, and mixed diarrhea. Secretory diarrhea is usually high-volume diarrhea and is caused by increased production and secretion of water and electrolytes by the intestinal mucosa into the intestinal lumen. Osmotic di-arrhea occurs when water is pulled into the intestines by the os-motic pressure of unabsorbed particles, slowing the reabsorption of water. Mixed diarrhea is caused by increased peristalsis (usu-ally from IBD) and a combination of increased secretion and de-creased absorption in the bowel.

Clinical Manifestations

In addition to the increased frequency and fluid content of stools, the patient usually has abdominal cramps, distention, intestinal rumbling (ie, borborygmus), anorexia, and thirst. Painful spasmodiccontractions of the anus and ineffectual straining (ie, tenesmus) may occur with defecation. Other symptoms depend on the cause and severity of the diarrhea but are related to dehydration and to fluid and electrolyte imbalances.

Watery stools are characteristic of small bowel disease, whereas loose, semisolid stools are associated more often with disorders of the colon. Voluminous, greasy stools suggest intestinal malab-sorption, and the presence of mucus and pus in the stools suggests inflammatory enteritis or colitis. Oil droplets on the toilet water are almost always diagnostic of pancreatic insufficiency. Noctur-nal diarrhea may be a manifestation of diabetic neuropathy.

Assessment and Diagnostic Findings

When the cause of the diarrhea is not obvious, the following di-agnostic tests may be performed: complete blood cell count, chemical profile, urinalysis, routine stool examination, and stool examinations for infectious or parasitic organisms, bacterial tox-ins, blood, fat, and electrolytes. Endoscopy or barium enema may assist in identifying the cause.

Complications

Complications of diarrhea include the potential for cardiac dys-rhythmias because of significant fluid and electrolyte loss (espe-cially loss of potassium). Urinary output of less than 30 mL per hour for 2 to 3 consecutive hours, muscle weakness, paresthesia, hypotension, anorexia, and drowsiness with a potassium level of less than 3.0 mEq/L (3 mmol/L) must be reported. Decreased potassium levels cause cardiac dysrhythmias (ie, atrial and ventric-ular tachycardia, ventricular fibrillation, and premature ventricular contractions) that can lead to death.

Medical Management

Primary management is directed at controlling symptoms, pre-venting complications, and eliminating or treating the underlying disease. Certain medications (eg, antibiotics, anti-inflammatory agents) may reduce the severity of the diarrhea and treat the under-lying disease.

Nursing Management

The nurse’s role includes assessing and monitoring the charac-teristics and pattern of diarrhea. A health history addresses the patient’s medication therapy, medical and surgical history, and dietary patterns and intake. Reports of recent exposure to an acute illness or recent travel to another geographic area are im-portant. Assessment includes abdominal auscultation and palpa-tion for abdominal tenderness. Inspection of the abdomen and mucous membranes and skin is important to determine hydra-tion status. Stool samples are obtained for testing.

During an episode of acute diarrhea, the nurse encourages bed rest and intake of liquids and foods low in bulk until the acute at-tack subsides. When food intake is tolerated, the nurse recom-mends a bland diet of semisolid and solid foods. The patient should avoid caffeine, carbonated beverages, and very hot and very cold foods, because they stimulate intestinal motility. It may be necessary to restrict milk products, fat, whole-grain products, fresh fruits, and vegetables for several days. The nurse adminis-ters antidiarrheal medications such as diphenoxylate (Lomotil) and loperamide (Imodium) as prescribed. Intravenous fluid ther-apy may be necessary for rapid rehydration, especially for the elderly and those with preexisting GI conditions (eg, IBD). It is im-portant to closely monitor serum electrolyte levels. The nurse im-mediately reports evidence of dysrhythmias or a change in the level of consciousness.

The perianal area may become excoriated because diarrheal stool contains digestive enzymes that can irritate the skin. The pa-tient should follow a perianal skin care routine to decrease irrita-tion and excoriation. It is important to use skin sealants and moisture barriers as needed. The older person’s skin is very sen-sitive because of decreased turgor and reduced subcutaneous fat layers.