Cystic Fibrosis
Is an autosomal recessive disorder affecting the exocrine glands, in which their secretions become abnormally viscous and liable to obstruct glandular ducts.
- It primarily affects pulmonary and GI function.
- The average life expectancy for the cystic fibrosis patient is currently age 30 to 40. Death may occur because of respiratory infection and failure.
- Other complications include esophageal varices, diabetes, chronic sinusitis, pancreatitis, rectal polyps, intussusceptions, growth retardation, and infertility.
Assessment:
- Usually present before age 6 months but severity varies and may present later.
- Meconium ileus is found in neonate.
- Usually present with respiratory symptoms, chronic cough, and wheezing.
- Parents may report salty taste when skin is kissed.
- Recurrent pulmonary infections.
- Failure to gain weight or grow in the presence of a good appetite.
- Frequent, bulky, and foul smelling stools (steatorrhea), excessive flatus, pancreatitis and obstructive jaundice may occur.
- Protuberant abdomen, pot belly, wasted buttocks.
- Bleeding disorders.
- Clubbing of fingers in older child.
- Increased anteroposterior chest diameter (barrel chest).
- Decreased exertional endurance.
- Hyperglycemia, glucosuria with polyuria, and weight loss.
- Sterility in males.
Diagnostic Evaluation:
- Sweat chloride test measures sodium and chloride level in sweat.
- Chloride level of more than 60 mEq/L is virtually diagnostic.
- Chloride level of 40 to 60 mEq/L is borderline and should be repeated.
- Duodenal secretions: low trypsin concentration is virtually diagnostic.
- Stool analysis:
- Reduced trypsin and chymotrypsin levels-used for initial screening for cystic fibrosis.
- Increased stool fat concentration.
- BMC ( Boehringer-Mannheim Corp.) meconium strip test for stool includes lactose and protein content; used for screening.
- Chest X-ray may be normal initially; later shows increased areas of infection, overinflation, bronchial thickening and plugging, atelectasis, and fibrosis.
- Pulmonary function studies (after age 4) show decreased vital capacity and flow rates and increased residual volume or increased total lung capacity.
- Diagnosis is made when a positive sweat test is seen in conjunction with one or more of the following:
- Positive family history of cystic fibrosis.
- Typical chronic obstructive lung disease.
- Documented exocrine pancreatic insufficiency.
- Genetic screening may be done for affected families.
Pharmacologic Interventions:
- Antimicrobial therapy as indicated for pulmonary infection.
- Oral or I.V. antibiotics as required.
- Inhaled antibiotics, such as gentamicin or tobramycin, may be used for severe lung disease or colonization of organisms.
- Bronchodilators to increase airway size and assist in mucus clearance.
- Pulmozyme recombinant human DNase (an enzyme) administered via nebulization to decrease viscosity of secretions.
- Pancreatic enzyme supplements with each feeding.
- Favored preparation is pancrelipase.
- Occasionally, antacid is helpful to improve tolerance of enzymes.
- Favorable response to enzymes is based on tolerance of fatty foods, decreased stool frequency, absence of steatorrhea, improved appetite, and lack of abdominal pain.
- Gene therapy, in which recombinant DNA containing a corrected gene sequence is introduced into the diseased lung tissue by nebulization, is in clinical trials.
Nursing Interventions:
- Monitor weight at least weekly to assess effectiveness of nutritional interventions.
- Monitor respiratory status and sputum production, to evaluate response to respiratory care measures.
- To promote airway clearance, employ intermittent aerosol therapy three to four times per day when the child is symptomatic.
- Perform chest physical therapy three to four times per day after aerosol therapy.
- Help the child to relax to cough more easily after postural drainage.
- Suction the infant or young child when necessary, if not able to cough.
- Teach the child breathing exercises using pursed lips to increase duration of exhalation.
- Provide good skin care and position changes to prevent skin breakdown in malnourished child.
- Provide frequent mouth care to reduce chances of infection because mucus is present.
- Restrict contact with people with respiratory infection.
- Encourage diet composed of foods high in calories and protein and moderate to high in fat because absorption of food is incomplete.
- Administer fat-soluble vitamins, as prescribed, to counteract malabsorption.
- Increase salt intake during hot weather, fever, or excessive exercise to prevent sodium depletion and cardiovascular compromise.
- To prevent vomiting, allow ample time for feeding because of irritability if not feeling well and coughing.
- Encourage regular exercise and activity to foster sense of accomplishments and independence and improve pulmonary function.
- Provide opportunities for parents to learn all aspects of care for the child.
- Teach the parents about dietary regimen and special need for calories, fat, and vitamins.
- Discuss need for salt replacement, especially on hot summer days or when fever, vomiting, and diarrhea occur.