Learning Objectives
By the end of this section, you will be able to:
- Discuss the pathophysiology, risk factors, and clinical manifestations for cystic fibrosis
- Describe the diagnostics and laboratory values in the disease of cystic fibrosis
- Apply nursing concepts and plan associated nursing care for the patient with cystic fibrosis
- Evaluate the efficacy of nursing care for the patient with cystic fibrosis
- Describe the medical therapies that apply to the care of cystic fibrosis
Cystic fibrosis (CF) is an inherited disease caused by a gene mutation. This mutation impacts how sodium and chloride ions travel across cell membranes. As a result, thick mucus accumulates in the lungs and throughout the body. Serious breathing problems and other physical issues occur. In the United States, more than 30,000 people are affected by CF. It is most common in White persons and especially persons of Northern European descent. In those populations, about one in 3,500 births is affected. CF is caused by a mutation affecting the CF transmembrane conductance regulator (CFTR) gene. Some people carry the gene but do not develop CF. Because of treatment advances, life expectancy has climbed for patients with CF. Currently, the median survival age for patients with CF is forty. While the pulmonary implications of CF are the primary cause of illness and death, it does affect other organ systems. There is a major treatment burden associated with CF, and recurrent hospitalizations are common (Brown et al., 2017; Karakashian et al., 2021).
Pathophysiology
CF is an inherited disease caused by a mutation in the CFTR gene. Because of the mutation, changes occur that affect how sodium and chloride ions move across cell membranes. When this movement is impaired, thick mucus builds up in the lungs and throughout the body (Figure 11.31). This causes breathing problems and affects other body systems. The thick mucus creates an optimal environment for bacterial colonization. Common infections include pseudomonas, Haemophilus influenza, and staphylococcus aureas. A person with CF experiences a major inflammatory response to the infection. Over time, the repeated cycles of infection and inflammation destroy parts of the airways.
Risk Factors
Because CF is an inherited disease, family history is the primary risk factor. If both parents carry the gene mutation, their offspring will have a one in four chance of developing CF and a one in two chance of becoming a carrier (Brown et al., 2017; Karakashian et al., 2021).
Signs and Symptoms/Clinical Presentation
Most people will be diagnosed with CF before age two when there are not yet obvious manifestations. Observable symptoms usually affect the gastrointestinal system first. Symptoms can manifest at birth; a neonate may present with an ileus from their first stool (meconium). Children may have a chronic cough, wheezing, and GI malabsorption. This can result in failure to thrive, growth restrictions, small stature, and decreased weight gain. Additional GI symptoms can include abdominal bloating, fatty stools, constipation, volvulus, intussusception, and biliary cirrhosis. Respiratory symptoms can include recurrent pneumonia, hemoptysis, shortness of breath, bronchiolitis, nasal polyps, and bronchiectasis. Over time, digital clubbing and increased anterior/posterior chest diameter can occur. Genitourinary symptoms associated with CF include decreased fertility, sterility, undescended testes, and congenitally absent vas deferens (Brown et al., 2017; Karakashian et al., 2021).
Assessment and Diagnostics
Timely diagnosis of CF is critical to ensure prompt access to treatment and care. Effective screening guidelines have been implemented. In the United States, all newborns are screened at birth for CF using a heel stick blood test. The average age at diagnosis is six to eight months and most patients are diagnosed prior to age two. If the initial blood test is positive, a sweat test is used for conclusive diagnosis. During a sweat test, a chemical and a small amount of electrical stimulation are applied to the skin to encourage sweat production. Over the course of thirty minutes, sweat is collected and sent to the lab for analysis. Elevated levels of sodium and chloride in the sweat confirm a diagnosis of CF. When an infection is suspected, a sputum culture and Gram stain can identify the organism so targeted treatment can be initiated. Liver function tests may show elevated results. A seventy-two-hour stool test can evaluate the presence of fecal fat and show increased fat and decreased albumin.
Imaging, most commonly chest x-ray, is used to assess disease progression and evaluate exacerbations. Pulmonary function testing is used to quantify disease progression and the severity of exacerbation. Arterial blood gas analysis can demonstrate hypoxemia and abnormally low blood pH. These results can support the initial diagnosis as well as provide information on disease progression (Brown et al., 2017; Karakashian et al., 2021).
Nursing Care of the Patient with CF
Nursing care of a patient with CF occurs across the life span, typically starting in childhood. While respiratory manifestations are prevalent, other body systems are also affected.
Recognizing Cues and Analyzing Cues
The nurse caring for a patient with suspected or confirmed CF evaluates both subjective and objective data. Prior to diagnosis, it is important to understand family history and known risk of inherited disease. The nurse assesses the patient and caregiver’s stress and emotional well-being as they face a chronic disease. In an infant, meconium ileus may be present. Parents may note salty sweat, gastrointestinal problems, or a chronic cough. In a patient with known CF, the nurse asks about difficulty breathing, secretions, and cough. Because CF is a systemic disease that affects more than the lungs, it is important to assess for gastrointestinal symptoms, such as bowel obstruction, malabsorption, and pancreatic insufficiency. Objectively, vital signs are evaluated with a focus on respiratory rate, oxygen saturation, and temperature. Lung sounds may demonstrate crackles or wheezing (Karakashian et al., 2021).
Prioritizing Hypotheses, Generating Solutions, and Taking Action
In patients with CF, respiratory status is a high priority. The nurse may need to monitor vital signs, prepare a patient for imaging, or administer medications. Medications may be oral, intravenous, or inhaled. Antibiotics are commonly needed. Many patients with CF will require supplemental oxygen. Gastrointestinal interventions may include evaluating food intake, administering pancreatic enzymes and salt tablets, and supporting bowel function. To improve airway clearance, collaboration with respiratory therapy (and sometimes physical therapy) is necessary. When patient and caregiver stressors are present, the nurse prioritizes their emotional well-being and coping skills by facilitating access to resources like support groups, financial assistance, and mental health counseling (Karakashian et al., 2021).
Evaluation of Nursing Care for the Patient with CF
Nursing care for patients with CF centers on managing secretions, airway clearance, and prevention and treatment of exacerbations. Evaluation considers patient history, physical assessment, and physiologic parameters. The most important outcomes related to CF are airway clearance, prevention of exacerbation, and increased life expectancy. Patient reporting, lung auscultation, direct observation of cough, and vital sign assessment can provide important information about airway clearance status and signs of exacerbation. Adequate hydration, nutrition, and elimination are important outcomes to monitor (CDC, 2021; Karakashian et al., 2021).
Medical Therapies and Related Care
The treatment of CF is complex and ongoing. Effective care requires close collaboration between the patient, caregivers, physicians, nurses, respiratory therapists, pharmacists, and rehabilitation therapists. Preventive care includes vaccination for preventable respiratory illnesses. Airway clearance therapy is necessary to help patients clear the thick, tenuous airway secretions. This can include manual chest percussion, a wearable high-frequency vest that delivers compression (Figure 11.32), flutter valve therapy, and mechanical ventilation. Inhaled medications, such as hypertonic saline and dornase alfa, can thin secretions, making it easier for mucus to be cleared. In children under eighteen, high-dose ibuprofen is utilized; studies have demonstrated that it decreases loss of lung function. When exacerbations occur, corticosteroids decrease inflammation and inhaled bronchodilators decrease airway hyperresponsiveness. Antibiotics are used during active infections and sometimes as prophylaxis. Some patients will be candidates for a lung transplant, which can extend life span by about five years in children and eight years in adults.
Because the gene mutation affects organs other than the lungs, additional treatment is required. Many patients with CF will experience digestion problems related to pancreatic insufficiency and require pancreatic enzymes supplementation as part of their treatment. In most male patients, the vas deferens is absent, but the body still produces sperm. In patients who want to consider reproduction, sperm can be harvested and used for assisted conception.