LOWER AIRWAY DISEASE

Acute respiratory illnesses are common among children. This chapter provides an overview of childhood respiratory illnesses commonly categorized as “lower airway diseases.” Despite the title of this chapter, there is no complete agreement among practitioners as to where the lower airway begins. In adults, the lower or small airways usually include those from the 16th generation and beyond. In children, they begin much more proximally. In this chapter, we refer to the “lower airways” as those airways below the thoracic inlet, which is approximately one-third of the way down the trachea. Thus, the “lower airway” diseases covered in this chapter include bronchiolitis, pneumonia, bronchitis, and bacterial tracheitis. We will begin by discussing the common viral and bacterial pathogens commonly associated with lower airway disease in children; then, we will discuss each of the common disease states in detail. Croup and epiglottitis, “upper airway diseases,” will be discussed in Chapter 6.

Many different organisms are capable of infecting the lower respiratory tract. The infections they cause will vary in type and severity. Infectious lower airway diseases can be caused by both viral and bacterial pathogens; however, most infections are viral in nature. Respiratory syncytial virus (RSV) is the most common virus causing lower respiratory illness. Influenza, parainfluenza, metapneumovirus, and adenovirus all have the potential to cause lower airway disease in children. Together with the myriad rhinoviruses, all of the above-mentioned viruses also have the potential to trigger an asthma exacerbation. Lower respiratory infections can result in numerous complications and they are particularly troublesome for patients with underlying chronic illnesses or compromised immune systems.

Of the bacteria, the most common infecting agents are Streptococcus pneumoniae, Staphylococcus, Haemophilus influenzae, Chlamydia pneumoniae, and Mycoplasma pneumoniae. Furthermore, S. pneumoniae and Staphylococcus can cause complications of a preexisting viral infection (Denny, 1999).

One of the most difficult challenges to the clinician is determining whether a given illness is viral or bacterial. Too often the decision is made to treat all children with lower respiratory symptoms with an antibiotic “just in case” a bacterial agent is involved. This practice is not only unnecessary and inappropriate but it can also ultimately be harmful because it can result in the selection of more resistant organisms. For this reason, both the Centers for Disease Control and Prevention (CDCP) and the American Academy of Pediatrics (AAP) are making efforts to reduce antibiotic use in children with lower airway disease.

Clinical features that suggest bacterial infections include an abrupt onset or change in symptoms, toxicity, radiographic findings of lobar consolidation or pleural effusion, and persistence and magnitude of fever. It is critical for practitioners to remember that viral infections remain the most common cause of lower respiratory illnesses. This knowledge must be taken into consideration when making clinical decisions regarding treatment. Treating with an antibiotic just in case will increase the risk of subsequent superinfection with a resistant organism. Bacterial superinfection can occur with some viral infections (especially influenza) 1–2 weeks after the onset of symptoms, when high fevers return with respiratory compromise.

Common Viral Agents That Cause Acute Lower Respiratory Infections in Children

RSV

RSV is the most common cause of bronchiolitis and viral pneumonia in children under 1 year; it is also the most common cause of acute lower respiratory infections (ALRIs) among children under 3 years of age (Centers for Disease Control [CDC], 2010). Outbreaks occur annually, usually starting in October or November in the Western Hemisphere, and can last up to 6 months. Acute lower airway disease is more common in younger patients, and the morbidity and mortality rates are higher in infants (CDC, 2010). In recent years, it has been estimated that more than 125,000 children under 4 years of age have been hospitalized in the United States for RSV disease during the first year of life (Krilov, 2010). Preexisting lung diseases, such as chronic lung disease of prematurity, increase the likelihood of severe disease. Because there are at least three strains of RSV, reinfection is possible and can result in a more severe illness (Dakhama et al., 2009). RSV infects older children and adults as well, causing a simple URI in otherwise normal subjects and triggering asthma symptoms in those with asthma.

RSV can be confirmed through a nasal wash or swab. Diagnosis can also be assumed through clinical symptoms and presentation. While many children are infected with RSV each year, some will have more serious symptoms requiring hospitalization and sometimes assisted ventilation. The most serious complications facing RSV-infected patients are apnea and respiratory distress. At times, infants under 3 months of age may develop apnea first as the only sign of RSV infection. Additionally, RSV has been linked to death in a number of cases (Poets, 2008).

Infants with recurrent apnea due to RSV infection may require ventilation until the apnea resolves, usually within a few days. Agitation, particularly if not resolved by supplemental oxygen, can be an indication of respiratory insufficiency in infants. In such children, it is mandatory to assess the degree of ventilation, best done with an arterial blood gas. Careful clinical assessment for signs of respiratory distress (nasal flaring, intercostal retractions, grunting, tachypnea, and tachycardia) and monitoring of pulse oximetry is essential when caring for an infant with RSV. A properly performed venous blood gas can give an indication of the degree of ventilation but is generally less accurate than an arterial blood gas.

Parainfluenza

Parainfluenza is another common cause of acute lower respiratory illness in children under 5 years (Dubois & Ray, 1999). The course of illness for parainfluenza is similar to that described above for RSV, and the management of the illness is generally the same. Parainfluenza is also a common cause of acute croup, which is discussed in Chapter 6.

Influenza

Influenza (types A and B) is a major cause of lower respiratory disease in children and can be fatal. Influenza viruses are categorized according to the type of hyaluronidase and neuraminidase they contain. (There are several of each types of enzyme resulting in the viruses being labeled HxNx.) Outbreaks generally occur in the cool winter months and spread quickly. Seasonal influenza rarely survives in the summer months. However, the 2009 H1N1 influenza first appeared in the spring, with the pandemic waning in August of that year. The pandemic then began again that September and persisted into February of the following year.

The clinical presentation of influenza differs from that of RSV or parainfluenza in that the symptoms often appear rapidly and become severe over the first 24 hours. Typically, fever and malaise develop first, followed by the onset of nasal congestion and cough. Although bacterial superinfection can occur at anytime, a more serious viral pneumonia can be seen within the first 2 or 3 days of the illness. Such a viral pneumonia can lead to acute respiratory distress. On the other hand, the bacterial superinfections are more likely to be seen 1–2 weeks after the onset of symptoms. In this scenario, the child is improving or stable when high fevers and varying degrees of respiratory compromise occur. A chest X-ray will often show lobar consolidation. Immune dysregulation by influenza has been suggested as at least part of the reason for this (Heltzer et al., 2009). Diagnosis of influenza can be made with rapid antigen screening and nasal cultures. Treatment is generally supportive as it is with other viral illnesses. Antiviral agents have been proven to be effective in shortening the course and severity of the illness if started within 1–2 days of the symptoms. The seasonal influenza virus has been adept at developing resistance to the commonly used antiviral agents. The 2009 H1N1 virus has not developed such resistance as of this writing. However, it is different from the seasonal influenza in that it causes more morbidity and mortality among young children. It has been recommended that high-risk children be prophylactically treated with antiviral agents if they have been in close contact with a person who has a known case of influenza. Bacterial superinfections should be treated with appropriate antibiotic therapy, keeping in mind the frequency of Staphylococcus in this scenario.

Currently, the CDC recommends that all children under the age of 18 receive the influenza vaccine, as this is the most effective way to prevent outbreaks and to protect children from serious consequences of the flu. Vaccination is especially essential for children who are at high risk, such as those with chronic pulmonary, cardiac, hematologic, immunologic, and metabolic conditions. In addition, household members of high-risk children should be immunized, as should all health-care workers and caregivers. High-risk children, or family members of such children, should not receive the live nasal vaccines.

Adenovirus

Adenovirus is a common cause of fever and upper respiratory illnesses in children but can sometimes cause lower respiratory illness as well. Adenoviral pneumonia causes the same type of symptoms as pneumonia from RSV or influenza; however, the symptoms may be more prolonged. Children with adenovirus are more likely to have a persisting fever and conjunctivitis is not uncommon. Adenovirus is also more likely to cause chronic sequelae, including interstitial fibrosis and bronchiectasis. Adenovirus is not susceptible to antiviral agents currently available, and therefore supportive therapy is all that is available for a patient with an ALRI caused by adenovirus.

Human Metapneumovirus

Human metapneumovirus (hMPV) is a viral pathogen that causes a wide spectrum of illnesses ranging from asymptomatic infection to severe bronchiolitis. First named in 2001, hMPV tends to affect mainly patients between newborn and 6 years of age. The pathophysiology of the virus is similar to that of RSV and it is found to be the causative virus in 5–15% of infant bronchiolitis. The clinical presentation is similar to that of RSV as well, presenting with symptoms such as rhinorrhea, congestion, cough, tachypnea, and dyspnea (Maranich & Rajnik, 2009). Treatment of a child infected with hMPV is primarily supportive, focusing on adequate hydration and oxygenation. Severe disease can lead to respiratory failure, implying that careful clinical observation is imperative, especially in high-risk infants and children.

Common Bacterial Agents That Cause ALRIs in Children

As noted previously, viruses cause the overwhelming majority of lower respiratory illnesses in children; thus, antibiotics should be used sparingly. The most common bacterial agents that cause community-acquired lower respiratory illnesses in children are S. pneumoniae, Staphylococcus aureus, H. influenzae, and the “atypical” organisms, C. pneumoniae, and M. pneumoniae. Given the current overuse of antibiotics, many of these and other organisms have developed resistance to first-line antibiotic treatment. This is especially true with the hospital-acquired organisms, which include S. aureus (including the methicillin-resistant strains) and the gram-negative organisms including Klebsiella, Enterobacter, Acinitobacter, and Escherichia coli. Often, this forces the clinician to use second-generation or multiple antibiotics to treat respiratory illnesses. Table 5.1 provides the common bacterial agents responsible for each of the community-acquired lower respiratory illnesses, as well as the estimated percentage of the illnesses caused by viruses (Dubois & Ray, 1999). These numbers confirm the limited need for antimicrobial treatment in most respiratory illnesses.

Table 5.1 Common bacterial pathogens in associated lower respiratory diseases.

Disease	Common bacterial pathogens	Estimated percentage caused by viruses
Pneumonia	Streptococcus pneumoniae, Staphylococcus aureus, Haemophilus influenzae type B, Mycoplasma pneumoniae, Chlamydia trachomatis	70–80
Bronchiolitis	C. trachomatis, Chlamydia pneumoniae, M. pneumoniae	90
Bronchitis	M. pneumoniae, C. pneumoniae, Bordetella pertussis, H. influenzae	80

Common Lower Airway Diseases in Children

As discussed earlier, this chapter will focus on the most common infections that occur below the thoracic inlet. These include bronchiolitis, pneumonia, bacterial tracheitis, and bronchitis. The diagnosis of bronchitis remains controversial in children. Each of these conditions carries with it specific implications and risks, all of which should be considered when caring for an infant or a child with a lower respiratory tract illness.

Bronchiolitis

Epidemiology

Bronchiolitis is an acute illness that usually occurs with an upper respiratory infection where the virus causes inflammation and obstruction of the bronchioles (small airways). It often occurs as a single episode. However, recurrent infections have been reported, often in the first year of life. The initial descriptions of bronchiolitis were of a first episode of wheeze, caused by a virus, in infants under 2 years of age (Everard, 2008). The overlap with asthma is considerable, including signs and symptoms, and the fact that children with RSV bronchiolitis have a higher incidence than the general population of subsequent asthma.

Bronchiolitis commonly affects infants and toddlers; however, it is most severe and troublesome in infants younger than 12 months of age. Infants less than 3 months of age, premature infants (less than 35 weeks’ gestation), and infants with chronic lung disease, congenital heart disease, or immune deficiency syndromes who develop bronchiolitis are at higher risk for hospitalization and death (Shay et al., 1999). Factors such as maternal cigarette smoking also increase the severity and perhaps the frequency of the disease. Careful clinical monitoring with early hospitalization to treat the potential morbidity should be the top priority in the management of bronchiolitis.

Preventive medical therapies such as palivizumab (Synagis^®) should be considered for high-risk patients. Palivizumab is a monoclonal antibody that has been shown to be effective at decreasing the incidence of serious RSV infection and RSV-related hospitalizations (The ImPACT-RSV Study Group, 1998). However, palivizumab is not advocated for every child. There are specific recommendations for palivizumab administration for infants who were born less than 35 weeks’ gestation and for those with congenital airway abnormalities, severe neuromuscular disease, and chronic lung disease (American Academy of Pediatrics [AAP], 2009).

Pathophysiology

Bronchiolitis occurs when viruses invade the mucosal cell lining in the bronchi and bronchioles, resulting in cell death. Cell debris then clogs and obstructs the bronchioles and irritates the airway. The irritated airway swells and develops excess mucus production, which results in airway obstruction. Air becomes trapped distal to the obstructed airways and interferes with gas exchange, leading to decreased oxygenation. Infants and small children are at higher risk of atelectasis.

Signs and Symptoms

Bronchiolitis is diagnosed primarily by clinical findings, the age of the child, and the season of the illness. It may be defined as an acute (first) wheezing episode in a child less than 2 years of age, especially during an RSV epidemic. Clinical findings include coryza, wheeze, crackles, and frequent cough. Fever may or may not be present. With progression to respiratory distress, nasal flaring, retractions, tachypnea, and labored breathing may be present. Other findings may include irritability, decreased appetite, and poor sleeping. Post-tussive emesis may consist of thick, clear mucus.

Diagnosis

A diagnosis is primarily made by history and physical exam in the proper season. It is recommended that routine diagnostic studies (chest X-ray, nasal washes/swabs, cultures, and blood gases) not be performed to determine viral infection status or to rule out bacterial infections. Such studies are not generally helpful and result in increased rates of unnecessary admissions, further testing, and unnecessary therapies (Bordley et al., 2004). Chest X-rays may be obtained as clinically indicated when the diagnosis of bronchiolitis is not clear or when a secondary bacterial infection is suspected. Secondary bacterial infections are not common during acute bronchiolitis, and radiographic abnormalities usually represent the underlying disease.

A chest X-ray of a patient with bronchiolitis will generally show nonspecific areas of inflammation. This may be described as peribronchial thickening or increased diffuse markings. These are the same findings seen in the radiograph of a child with acute asthma. As in acute asthma, hyperinflation is not uncommon and areas of atelectasis may be interpreted as infiltrates. Arterial blood gases may be clinically indicated in a patient who is in respiratory distress and in need of further respiratory support. Pulse oximetry is an important measure for children admitted with bronchiolitis.

Complications

The major complications of bronchiolitis are apnea and respiratory failure. Bacterial superinfection is very rare. The long-term morbidity in infants affected by bronchiolitis has been addressed in many studies. As many as 75% of infants who have been hospitalized with RSV have recurrent wheeze and cough episodes in the first few years of life (Young, O’Keeffe, Arnott, & Landau, 1995). While some may be experiencing their first asthma episodes, at these ages, there is no test to distinguish between an asthma episode and a wheeze-associated viral illness. Other than infant pulmonary function testing, which requires sedation in a specialty laboratory, the best way to determine the diagnosis of asthma is through a clinical trial of inhaled beta-agonists. The child with recurrent episodes of wheezing is more likely to have asthma and to respond to therapy. The child with a first episode, in the proper age range, is less likely to respond. If a child does not respond to beta-agonists, the continued use of these treatments is unwarranted.

Management

The basic management of bronchiolitis is to maintain adequate oxygenation and hydration. Hospitalization is necessary for infants with acute bronchiolitis if the above criteria are not able to be maintained at home. Management of the child hospitalized with bronchiolitis includes carefully monitoring their clinical status, maintaining a patent airway, suctioning the nose, maintaining hydration, and providing parent education.

Oxygen therapy is frequently required in the treatment of bronchiolitis. For human beings at sea level, oxygen saturation above 90% is adequate and safe. Infants, however, may have lower reserve, and the ready obstruction of an airway may acutely lower the oxygenation. Thus, it is recommended to consider starting supplemental oxygen when the oxygen saturation is consistently less than 91% and to consider weaning supplemental oxygen when the oxygen saturation is consistently higher than 94% (Bye, 1994).

Albuterol aerosol therapies should not be routinely used as they have not been proven to be helpful in the majority of cases, despite the fact that many of these children will subsequently develop asthma. In the majority of cases, the use of inhalation therapies and other treatments effective for treating asthma will likewise not be efficacious. A meta-analysis of randomized, controlled trials has not shown dramatic effects on clinical scores or hospitalization rates from therapy with nebulized albuterol in children with bronchiolitis (Gadomski & Bhasale, 2006).

Antibiotics, antihistamines, steroids (oral or inhaled), and decongestants should not be routinely used in patients with bronchiolitis as they have not been found to be helpful. Additionally, chest physiotherapy (CPT) and cool mist therapy have not proven to be clinically helpful. There are some data to suggest that inhaled epinephrine may help acutely (Sanchez, Koster, Powell, Wolstein, & Chernick, 1993). It is not clear if this is an action at the nose or in the airways. However, in children with acute respiratory insufficiency who do not respond to albuterol, epinephrine may be tried. Nebulized hypertonic saline may have some benefit in decreasing length of stay (Kuzik et al., 2007).

Careful, frequent clinical assessment of the child is essential to the successful treatment of bronchiolitis. Cardiac and respiratory rate monitoring should be initiated in hospitalized patients. Oxygen saturations should also be monitored to assure oxygenation saturations are at acceptable levels. Premature infants, infants with underlying chronic conditions, and infants less than 3 months of age who contract RSV are at particular risk of severe complications such as apnea or respiratory failure. Furthermore, several studies have reported more severe progression of the disease in children with bronchiolitis who present with low initial oxygen saturations (Wang, Law, & Stephens, 1995).

Nursing Care of the Child and Family

Nursing care focuses on assessing respiratory function, maintaining adequate hydration, and supportive measures. Nursing activities and treatments should be clustered to allow the infant as much rest time as possible and to decrease infant stress. Supportive measures include suctioning of the nose as needed. It is important to remember that coughing is the most effective method of clearing the airway. It is more effective than suction catheters, which have the potential to cause airway edema and laryngospasm.

Contact isolation precautions and frequent hand washing are helpful in preventing the spread of RSV bronchiolitis, as it is highly contagious. Because the virus lives on surfaces, contact with the baby and/or the crib or nightstand will result in the transmission of the virus to the hands of the care provider. This form of transmission can contribute to spreading of the virus to other patients. To prevent spread, it is also important that nurses and other personnel providing care to children with bronchiolitis are not also caring for children with underlying diseases, which put them at high risk for severe RSV disease.

Additionally, the nurse should perform a psychological assessment of the family to observe for signs of fear and anxiety, which can be prominent and worsen with respiratory distress. The nurse can help to reduce anxiety by providing thorough explanations and updates. Emotional security can be promoted by allowing parents to participate in as much of the infants’ care as possible.

The nurse should also provide anticipatory guidance for discharge, as symptoms may persist for weeks after discharge. The median duration of illness for children under 24 months with bronchiolitis is 12 days; after 21 days, approximately 18% will remain ill, and after 28 days, 9% will remain ill (Bronchiolitis Guideline Team, Cincinnati Children’s Hospital Medical Center, 2005). Discharge instructions should include proper techniques for suctioning the nose and making breathing easier as well as monitoring the clinical status of the child so a health-care provider can be notified if symptoms worsen. Parents should be made aware of the following warning signs: increasing respiratory rate and/or work of breathing as evidenced by accessory muscle use, inability to maintain adequate hydration (specific guidelines should be given based on the age and weight of the patient as to how much liquids should be consumed and how many wet diapers are adequate per day), recurring fever, and a worsening general appearance.

Pneumonia

Epidemiology

Pneumonia is the sixth leading cause of death in the United States, the second most common nosocomial infection, and the leading cause of death from nosocomial infections (CDC, 2010). Approximately 10–20% of all children under 5 years of age in developing countries develop pneumonia each year. Nearly 75% of pneumonia deaths occur among infants under 1 year old (Crawford & Daum, 2008). The risk of death is increased with malnutrition, malaria, and suppressed immunity. According to the World Health Organization, pneumonia is the single largest cause of death in children worldwide. Every year, an estimated 1.8 million children under the age of 5 die from pneumonia, accounting for 20% of all deaths in that age group (Rudan, Boschi-Pinto, Biloglav, Mulhollandd, & Campbelle, 2008).

There are approximately 155 million cases of childhood pneumonia each year in the world. Despite the fact that most pneumonias are easily treated with antibiotics, many children in underdeveloped nations lack access to these medications, contributing to the high mortality rate. Because of the lack of access to medications, malnutrition, crowding, and poor hygiene, pneumonia in developing countries is easily spread and is often fatal.

The overwhelming prevalence of pneumonia warrants its status as a major health concern that needs considerable attention and proper treatment. It can be classified as community-acquired pneumonia (CAP) or nosocomial pneumonia (indicating that the pneumonia developed while the patient was already in a hospital setting). The diagnosis of clinical pneumonia is often given in developing countries to indicate infection of the lower respiratory tract based on signs of fever, cough, and retractions. This is more common when diagnostic measures such as chest X-ray and laboratory studies are not readily available. However, the diagnosis of clinical pneumonia in the United States is becoming increasingly popular and often leads to the unnecessary use of antibiotics and the subsequent antibiotic resistance that is emerging.

Pathophysiology

Pneumonia is an infection of the lung. It indicates either a bacterial or viral infection of the lung parenchyma or interstitium. The etiology of pneumonia depends on many factors including the age of the patient, the setting in which the pneumonia was acquired (hospital vs. community), the vaccination status of the child, relevant exposures such as to contaminated water, host factors such as underlying diseases that predispose to pneumonia, and relevant local epidemiology such as local RSV outbreaks. However, even with all the relevant information, determining the etiology of the pneumonia is not easy and is often not attempted. Because of the invasiveness and cost of the measures needed to determine the etiology, pneumonia with mild or moderate symptoms is often treated based on current knowledge and generalizations.

The most common causes of bacterial pneumonia in the neonate are Group B B-hemolytic streptococci (GBS), and gram-negative enteric bacilli, such as E. coli. Among infants beyond the neonatal period, viruses are the most frequent etiologic agents in CAP, although both viral and bacterial agents can cause pneumonia simultaneously. Among the bacterial agents, Streptococcus pneumonia and S. aureus are the most common. Haemophilus influenzae type B (Hib) used to be a common causative agent but is much less so due to the development of the Hib vaccine, which is now routinely administered to children in the United States. M. pneumoniae is an important consideration among school-age children. Factors that alter an individuals’ risk of developing CAP include

• Age (<2 years, >65 years)
  
• Smoking, including passive smoke exposure in the home
  
• Underlying pulmonary diseases
  
• Cardiac diseases
  
• Malnutrition
  
• Low birth weight
  
• Central nervous system dysfunction, with recurrent aspiration
  
• Immunosuppression
  
• Lack of immunizations
  
• Crowding

Signs and Symptoms

In children beyond the neonatal period, it may be difficult to distinguish between viral and bacterial pneumonia. Overall, children with bacterial pneumonia may appear to be sicker and have a higher fever; however, this is not always the case. Wheezing is much more common with viral disease and extremely uncommon with bacterial disease. Because a bacterial pneumonia is more likely to be focal, the degree of hypoxemia may be less, but the degree of toxicity may be higher. Cough is generally present but is not always universal, and the production of sputum in a child under the age of 8 is rare. Abdominal pain and emesis are also variable complaints; however, these symptoms are sometimes so severe that diagnosis of the pneumonia is delayed while looking for abdominal conditions as the cause of the fever and pain.

On auscultation, crackles, evidence of pulmonary consolidation, tubular breath sounds, decreased breath sounds, and increased fremitus may be found. However, none of these are specific for pneumonia. With pleural effusion, decreased breath sounds, egophony, and dullness on percussion may be noted in the cooperative child.

General signs of respiratory compromise are present in severe cases and can include shallow breathing, tachypnea, grunting, retractions, and nasal flaring.

Diagnosis

Diagnosis is generally made through history, clinical exam, and chest X-ray. A detailed history should include duration and extent of fever, pain, weight loss, identification of risk factors, and onset of symptoms. Once the diagnosis is made, determining its etiology can be challenging. Often little is done beyond a complete blood count (CBC) and blood culture to determine the cause of the pneumonia. As a result of this, it is estimated that more than 80% of patients who have “nonbacterial pneumonia” receive bacterial antimicrobial treatment (Crawford & Daum, 2008).

If the child is able to produce sputum, a sample can be obtained for culture and sensitivity to identify the causative agent, make the diagnosis, and determine the appropriate treatment. In addition to the culture, the sputum Gram stain can be helpful. A CBC revealing an elevated white cell count and high levels of neutrophils and/or polymorphonucleocytes can be an indication of a bacterial process, but studies have not shown this to be highly specific or sensitive. Serologic studies of the blood and/or urine can be helpful in detecting an acute infection.

Additional diagnostic tests include oxygen saturation level and electrolytes if warranted. Some organisms, particularly Legionella species, are associated with the syndrome of inappropriate antidiuretic hormone, resulting in abnormalities in serum electrolytes. In the hospitalized patient, additional tests may include culture of pleural fluid if present and bronchoscopy to assist in the identification of the causative organisms. The latter is reserved for children who are severely ill or who have compromised immune function.

Complications

Complications from pneumonia can be life threatening and require immediate intervention. If the patient is failing to respond to therapy and overall appearance is deteriorating, other causes should be investigated as pneumonia may have been an incorrect diagnosis. Similarly, the patient may not be responding due to improper or insufficient antimicrobial therapy. It is helpful to know the resistance patterns of the common organisms in your area. This information should be readily available from hospital infectious disease specialists.

Sepsis, pleural effusion, and acute respiratory distress syndrome (ARDS) are potential complications of bacterial pneumonia that can cause serious and sometimes fatal outcomes. Although they are not the focus of this chapter, a brief description of these complications and their general management are described in this section. Sepsis, also known as the systemic inflammatory response syndrome (SIRS) is a serious systemic response to bacteremia or another infection. Septic shock is manifested by life-threatening low blood pressure (shock) due to bacteremia. Sepsis can be the result of bacterial infections, most often those that are acquired in a hospital. However, even aspiration pneumonia, which is usually a nonbacterial process, can be associated with the sepsis syndrome. A weakened immune system or a cardiac abnormality puts a patient at higher risk of acquiring sepsis. Because the patient response to sepsis is systemic, careful monitoring for the following signs is imperative: an abnormally high fever, hypothermia, tachypnea, tachycardia, and increased or markedly decreased white blood cell (WBC) count. As sepsis worsens, other organs begin to malfunction and blood pressure may decrease. Septic shock is diagnosed when blood pressure remains low despite intensive treatment. Generally, a suspicion of sepsis is made based on symptoms and should lead to blood cultures and careful evaluation of cardiovascular and respiratory function. However, antibiotics are initiated even when the diagnosis of sepsis is suspected. Oxygen is administered and fluids are given to increase and stabilize blood pressure. Assisted ventilation, whether noninvasive or through an endotracheal tube, is often necessary. In the United States, about 90,000 people die of septic shock each year (Dellinger, 2010).

A pleural effusion is an abnormal collection of fluid in the pleural space resulting from excess fluid production or decreased absorption. Effusions can also develop from direct irritation of the pleural membrane by the underlying pneumonia, resulting in fluid exudation into the pleural space. Pleuritic chest pain, chest pressure, dyspnea, and cough are the most common symptoms of pleural effusion. Cough is usually related to the associated disorder or to compression atelectasis, which accompanies many pleural effusions. Classic physical findings associated with pleural effusions include diminished breath sounds, dullness to percussion, and reduced tactile and vocal fremitus. After the initial stabilization of the patient, the pleural effusion should be confirmed with appropriate radiographic evaluation. The most frequently ordered studies are chest X-ray, ultrasonography, and computed tomography (CT). Chest X-ray is the primary diagnostic tool because of its availability, accuracy, and low cost. It may both confirm the presence of the effusion and suggest the underlying etiology. Bacterial pneumonias are associated with pleural effusions as often as 50% of the time (Duke & Good, 2001). Complicated parapneumonic effusions include empyema (the finding of pus in the pleural space), those with positive pleural fluid cultures or Gram stains, and those in which the microbiology is negative but the patient continues to show signs of infection with fever, severe pain, and leukocytosis. Complicated parapneumonic effusions often require drainage by tube thoracotomy. Some surgeons are now able to evacuate the effusion through video-assisted thoracoscopic surgery (VATS), resulting in a more complete evacuation of the fluid and shorter chest tube time. The patient who has pneumonia with a small amount of pleural fluid present and is clinically responding to antibiotic therapy (afebrile, no pleuritic pain, minimal oxygen requirements, minimal respiratory difficulty) does not require thoracentesis. By contrast, rapid accumulation of pleural fluid in a patient with pneumonia is an indication for immediate thoracentesis.

ARDS is an acute condition characterized by bilateral pulmonary infiltrates and severe hypoxemia resulting from increased alveolar–capillary permeability. ARDS is considered the pulmonary manifestation of the SIRS (Gutierrez, Duke, Henning, & South, 2008). Physical findings often are nonspecific and include tachypnea, tachycardia, and the need for high inspired oxygen concentrations to maintain oxygen saturation. The patient may be either febrile or hypothermic. Because ARDS often occurs in the context of sepsis, associated hypotension and peripheral vasoconstriction with cold extremities may be present. Examination of the lungs may typically reveal bilateral crackles. No specific therapy for ARDS exists. Systemic corticosteroids have had varying degrees of success; other anti-inflammatory agents are being studied. Treatment of the underlying condition is essential, along with supportive care and appropriate ventilator and fluid management. Because infection is often the underlying cause of ARDS, careful assessment of the patient for infected sites and institution of appropriate antibiotic therapy are essential. Patients with ARDS often require high-intensity mechanical ventilation, including high levels of positive end-expiratory pressure (PEEP) or continuous positive airway pressure (CPAP), which can lead to further complications. The mortality rate in children with ARDS can be as high as 40% (Gutierrez et al., 2008).

Pneumothorax is an uncommon complication of pneumonia and is usually associated with S. aureus pneumonia. This complication is first visible only by chest CT, but it can be seen on a plain chest X-ray as it develops. However, pneumothorax can be suggested if the child has a sudden worsening in oxygenation status, with decreased air flow on one side, and shift of the trachea.

Management

The management of a child with pneumonia varies depending of the age of the child, the immunologic status of the host, and the severity of the symptoms. Hospitalization is generally suggested in an infant younger than 4–6 months of age. Management of pneumonia in older children may or may not include hospitalization, depending on the severity of the illness and the ability of the child to maintain adequate oxygenation and hydration. Empiric antibiotic therapy should be initiated promptly if a bacterial process is suspected. This therapy should, based on the likely organisms, take into account the patients’ age, clinical state, and risk factors. Antibiotic therapy may need to be adjusted as the identification of causative organisms becomes known and the response of the patient to the therapy is evaluated.

Additionally, several supportive care measures may be needed. Oxygen therapy should be used to maintain oxygen saturation above 91%, and hydration and nutritional support is often necessary in hospitalized patients. If the child develops respiratory distress and the inspired oxygen concentration is high, noninvasive or invasive mechanical ventilation may be warranted. In any patient with pneumonia, whether in the hospital or treated at home, adequate fluid intake should be encouraged, and nonsteroidal anti-inflammatory drugs should be initiated to treat pain and fever.

Additional testing should be performed if a child presents with recurrent pneumonia. Recurrent pneumonia is classified as a child that has had at least two episodes of bacterial pneumonia confirmed on chest X-ray in 1 year, or more than three episodes at any age, with clearing of the X-ray between episodes. The evaluation of a child with recurrent pneumonia often depends on the radiographic picture (Bye, 1994). One should consider performing a bronchoscopy if the infiltrates are always in the same area. To make this determination, it is first important to ensure that the current pneumonia clears radiographically, usually within 6–8 weeks. It is then important to document the location of subsequent episodes. While the decision to conduct further testing should be dependent on the child’s presentation, testing should be directed toward conditions that can predispose a child to pneumonia. Thus, further evaluation might include testing for cystic fibrosis, congenital and acquired immunodeficiency, and immotile cilia syndrome.

Nursing Care of the Child and Family

Pneumonia can be a frightening diagnosis both to the child and the child’s parents or caretakers. Reassurance and proper teaching is needed to ensure the best possible outcome for the patient and the least amount of stress for the family. The parent or caregiver should be taught the signs to monitor that would indicate poor response to treatment or a worsening condition. Signs that warrant immediate attention include elevated respiratory rate (it is ideal to teach the parents how to take the rate when the child is asleep and give them guidelines for abnormal rates, which will vary with age), persisting fever after 72 hours or a fever that resolves and then returns, cyanosis, tachycardia, confusion, signs of dehydration (dry mucus membranes, absence of tears, and decreased urinary output), difficulty breathing, increased work of breathing, shortness of breath, or respiratory distress. When providing this education, it is important to explain these signs in terms the parents can understand. The family should be told how to contact the health-care provider if needed. Arrangements for proper follow-up should be made before the child leaves the office or is discharged.

Anticipatory guidance should be given to the family to help reduce subsequent infections. Parents should be encouraged to have their children receive a yearly influenza vaccine and the pneumococcal vaccine. They should also be encouraged to practice frequent hand washing and to avoid exposures to smoke and other risk factors.

Bronchitis

Epidemiology

Bronchitis is a commonly diagnosed respiratory problem in children. Most simply, it is an inflammation of the large airways. It usually occurs as part of a viral upper respiratory infection. It can also occur as a component of asthma, cystic fibrosis, immunodeficiencies, immotile ciliary syndrome, and other chronic respiratory conditions. Cough is the primary symptom leading to a diagnosis of bronchitis. Since cough is so common in children, care must be given in making the diagnosis of “bronchitis.” In children, a diagnosis of chronic bronchitis is not an acceptable end point and further testing should be performed to evaluate the underlying cause of the cough.

Bronchitis is categorized into acute, recurrent, or wheezy bronchitis; however, the definition of each type remains unclear and controversial. In school-age children, M. pneumoniae has occasionally been identified as an organism producing acute bronchitis (Brown, Mutius, & Morgan, 2008). There are no characteristic clinical findings to distinguish this diagnosis from viral bronchitis. Confirmation could only be accomplished with titers or microbiological evaluation of the sputum or bronchoalveolar lavage fluid. Serology is likely more sensitive because of the fastidious nature of Mycoplasma. If indicated, treatment with a macrolide antibiotic can be effective. Because titers are not commonly obtained, overtreatment with macrolides has become common in the pediatric outpatient setting.

In the absence of exposure to cigarette smoke, the persistence of bronchitis beyond 2–3 weeks or the recurrence of bronchitis warrants further investigation into the underlying causes. While the definition of recurrent bronchitis is controversial, most clinicians agree that “too many” episodes can be clarified as more than four episodes of productive cough each year with wheezes or crackles. If this criterion is met, alternative diagnosis should be considered.

The presentation of wheezy bronchitis and asthma often overlaps, and the overwhelming majority of these children actually have asthma. An Asthma Predictive Index is helpful in predicting persisting asthma in children with recurrent wheezing. In a child with three or more wheeze episodes a year, the index is positive if a child has one major criteria (parental asthma or eczema) or two or more minor criteria (allergic rhinitis, wheezing apart from colds, and peripheral eosinophilia) (Castro-Rodriguez et al., 2000). Focusing therapy on asthma in these situations is the most helpful approach. Careful considerations should be given to the child who is chronically diagnosed with bronchitis or wheezy bronchitis to evaluate for underlying conditions such as cystic fibrosis.

Persistent bacterial bronchitis has been recently described, as a wet cough in children who may be at risk of developing bronchiectasis without a known underlying disorder (Chang, Redding, & Everard, 2008). Persistent bacterial bronchitis may cause recurrent or protracted wet cough. Its true nature and existence are not well defined as yet.

Pathophysiology

Despite the common trend of pediatric providers to administer antibiotics for bronchitis, most attacks of acute bronchitis are viral. Rhinovirus, RSV, influenza, metapneumovirus, adenovirus, and rubeola virus have all been identified as etiologic agents (Brown et al., 2008). Because bronchitis is usually mild and self-limited, the pathology is ill defined as there is a lack of tissue to study. Mucus gland activity increases and desquamation of the ciliated epithelium occurs. Infiltration of leukocytes into the airway contributes to the purulent appearance of the secretions. Since leukocyte migration is a response to the airway damage, it is not necessarily indicative of a bacterial superinfection and should not be treated as such. Additionally, acute airway inflammation may also be caused by breathing irritants such as chemical fumes, dust, or smoke. Living in an area that has bad air pollution may predispose a child to more frequent episodes of bronchitis. Children may also be more likely to develop bronchitis if they are often around someone who smokes. Of course, all of those factors also increase the likelihood of asthma.

Signs and Symptoms

As mentioned, acute bronchitis usually accompanies an upper respiratory infection. Dry cough generally appears 2–4 days after the rhinitis and then evolves into a looser cough with sputum production. Since children do not always expectorate sputum (it is often swallowed), nausea and vomiting following cough spasms can occur. Chest pain is a common complaint in older children as the cough progresses and becomes more frequent and severe. In the early stages of the illness, the chest is generally clear to auscultation; however, as the illness progresses, rhonchi, wheezes, and harsh breath sounds can be heard. Crackles are rare. Chest X-ray is typically normal, although some increased markings can be noted. Symptoms gradually improve and typically disappear within 10–14 days. Symptoms that persist beyond 2 weeks or that worsen over time should be carefully evaluated for an underlying chronic condition or a secondary bacterial infection. Similarly, persisting fever should prompt evaluation. Although much has been made of the color of the secretions, there are no data to support this concern.

Complications

Most children recover completely after acute bronchitis as the illness is generally mild and self-limiting. Some children may develop other complications such as a sinus or ear infection. Rarely, bronchitis may develop into a more serious infection, such as pneumonia. This risk is increased if the child is very young or has other chronic health problems.

Management

If bacterial infection is suspected or confirmed, treatment with appropriate antimicrobial therapy is warranted. Using antibiotics to “prevent” pneumonia is ineffective and will contribute to the development of resistant organisms. Additionally, if the child is very young and the cough is impeding drinking and eating, hospital admission and IV therapy may be indicated to prevent dehydration. Rarely, oxygen support is needed to maintain adequate oxygenation.

Nursing Care of the Child and Family

Nursing care of a child ill enough to be hospitalized with bronchitis should include continuous monitoring of respiratory status, vital signs, and hydration status. Efforts should be made to encourage deep breathing and breathing through pursed lips. Children should be encouraged to expectorate sputum after coughing, and the head of the bed should be elevated to promote easier breathing.

Parents should be educated as to the signs of a worsening respiratory condition and when to take the child back to the health-care provider. Prevention of further symptoms should be discussed. This includes instructing patients regarding the need for immunization for pertussis and influenza to reduce further infection with those potentially harmful organisms. Additionally, parents should be encouraged to avoid other factors that can contribute to bronchitis including exposure to tobacco smoke and air pollutants, such as wood smoke, solvents, and cleaners. In order to limit the spread of the disease, children with acute bronchitis with fever should not attend school or day care. The child should return to school or day care when signs of infection have decreased, appetite returns, and alertness and strength resume.

Bacterial Tracheitis

Epidemiology

Bacterial tracheitis is a rare but life-threatening illness characterized by thick membranous tracheal secretions. The secretions are usually infected, as the name would suggest. The secretions are difficult to clear with coughing and can occlude the airway. Bacterial tracheitis is often a complication of croup and affects the same population, with a mean age of 4. Some feel bacterial tracheitis is mimicking croup initially. In one study, it was reported that of the 500 children who were hospitalized for croup at one pediatric hospital over a 32-month period, 2% developed bacterial tracheitis (Tan & Manoukian, 1992). It has also been recognized as a complication of measles.

Pathophysiology

The most common bacterial cause of tracheitis is S. aureus. Additionally, Hib (although rare now due to the vaccine), Moraxella catarrhalis, Klebsiella pneumoniae, and S. pneumoniae can cause bacterial tracheitis. Cases usually occur in the fall or winter months, mimicking the epidemiology of viral croup.

Signs and Symptoms

Bacterial tracheitis presents with severe upper airway obstruction, often in a child who has had a preceding episode of viral croup. Many, but not all, children present with high fever and systemic toxicity. Bacterial tracheitis is a diffuse inflammatory process of the larynx, trachea, and bronchi.

Diagnosis

Bacterial cultures of the tracheal secretions are needed in order to determine the infecting organism. A CBC will show an elevated WBC count, which is nonspecific and nondiagnostic. Blood cultures are usually negative. A lateral neck X-ray may reveal the subglottic narrowing from the preceding croup and tracheal irregularities. A definitive diagnosis is made through laryngoscopy and tracheoscopy (Asher & Grant, 2008). However, a clinical diagnosis can be made in a child who, after a few days of croup, develops high fever, increasing stridor, and respiratory distress.

Complications

While most children who are properly diagnosed and treated in the early phase of the disease recover completely, serious complications can occur. Toxic shock syndrome, pulmonary edema, and septic shock have all been reported as complications of bacterial tracheitis. A delay in treatment or improper management can result in ARDS and sometimes death from airway obstruction.

Management

Upon initial diagnosis, the child should be admitted to the pediatric intensive care until stabilized. More than half of the children will need to be intubated, and intermittent positive pressure breathing is sometimes needed. In many cases, the endotracheal tube will suffice, as it bypasses the obstruction and allows for adequate ventilation while the antibiotics work and the airway heals. Intubation often lasts from 3 to 11 days.

Antibiotics should be promptly initiated and should cover the above organisms. Gram stain of the secretions may allow narrowing the spectrum of antibiotics. There is no evidence that nebulized epinephrine or corticosteroids relieve the obstruction.

Nursing Care of the Child and Family

Caring for a child with bacterial tracheitis requires the nurse to be attentive to both the child and the family, as it is a stressful and potentially life-threatening illness. Direct nursing care must include maintaining a patent airway, frequent suctioning, monitoring for adequate ventilation, oxygenation, hydration, and nutritional status. CPT may help in clearing the secretions if it is tolerated by the child. The nurse should also be aware of the age-appropriate signs and symptoms of acute respiratory distress and should notify the medical team immediately if the child’s condition is worsening. Additionally, the nurse should provide anticipatory guidance to the family as to the expected course of the illness and should try to assist the family by providing answers to the concerns and questions they may have. The family should be reassured that long-term sequelae of tracheitis are very uncommon, as are recurrences of disease.

CONCLUSION

When caring for a child with any of the lower airway diseases described previously, the practitioner must take special care to monitor respiratory status but also must carefully weigh the need for antimicrobial therapy. As has been pointed out many times in this chapter, viral organisms are responsible for a majority of lower airway diseases in children and should be considered first when initiating treatment plans.

Much morbidity and mortality is arising as a result of the developing antibiotic resistance in the pediatric community. An example of the dangers of antibiotic resistance is the spread of methicillin-resistant Staphylococcus aureus (MRSA). MRSA was once a concern only for people in the hospital but now is causing infections in healthy people in the community. It is apparent from the above-mentioned discussion and data that in many cases, antibiotic therapy is not warranted and should be avoided to help limit the development of resistant organisms and more severe disease.

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