Coretta brought her eight-month-old daughter, Sasha, to see her nurse practitioner (NP). Since the night before, the baby was coughing and “making funny breathing noises.” She told the NP that for three days before the cough started, Sasha had a runny nose and a slight fever. However, she added that Sasha was breastfeeding well, and she was still wetting about eight diapers a day. The NP noted that Sasha’s respirations were unlabored at 36/minute with mild expiratory wheezes. Other than some nasal congestion, her physical exam was normal.

In another part of town, Jennifer took her four-month-old son, Jimmy, to see his primary care provider. Jennifer stated that Jimmy hadn’t been taking his formula very well. She said he had a cold with a slight cough over the past four days and has had to stay home from day care. This morning, the baby was coughing much harder and seemed to be breathing very rapidly. Jimmy’s respirations were labored at a rate of 54/minute with intercostal chest retractions and flared nares. Auscultation revealed generalized wheezing. Jimmy also appeared dehydrated with little urine output over the past 24 hours.

Respiratory symptoms are often a primary reason parents seek healthcare for their children. A common causative agent of respiratory illness in infants and toddlers is respiratory syncytial virus — so common, in fact, that 90% of children have been infected with RSV by the time they reach the age of two.¹ RSV outbreaks are predictable in that they occur annually with cases being reported beginning in November or December and lasting through spring. According to 2004–2005 reporting data, RSV activity appeared highest during December for the South and Northeast, during January for the West, and during February for the Midwest.²

In most young children, RSV results in only a mild upper respiratory infection that is indistinguishable from the common cold. RSV infection is usually self-limiting and can often be treated on an outpatient basis. However, in high-risk infants RSV can cause serious lower respiratory tract involvement, and even death.

Those at greatest risk for RSV bronchiolitis are born prematurely, have complicated congenital heart disease, suffer underlying lung conditions, or are immunosuppressed.³ Additionally, those who live in crowded conditions, are exposed to passive smoking, attend day care, have older siblings who might harbor causative organisms, or have not been breastfed are all more vulnerable.³ Interestingly, breast milk has been shown to have immune factors to RSV. To date, 33 studies have revealed a protective association between breast milk and the immune factors.⁴

The Face of RSV

Replicating in the nasopharynx, RSV is highly contagious and readily spread from hands to the eyes and nose by large particle aerosols. The virus has been isolated from fomites, and according to the Centers for Disease Control and Prevention, it can live on impervious surfaces such as bed rails for more than five hours.⁵ Caregivers can easily contaminate their hands and can be a source of transmission.

RSV-bronchiolitis is an acute, infectious respiratory illness with a peak incidence between two to six months of life.³ It often starts with such common cold symptoms as rhinorrhea, nasal congestion, low-grade fever, irritability, restlessness, and cough. As the condition worsens, the infant has to work harder to breathe. Nasal flaring, grunting, tachypnea, and retractions often develop.³ From what seems like a case of the sniffles, babies with RSV bronchiolitis may deteriorate quickly. In the short term they can suffer respiratory muscle fatigue, hypoxemia, and apnea. If the virus infects only the upper respiratory tract, the symptoms last from four to six days. In contrast, when the lower respiratory tract is involved, the disease can linger from one to two weeks.

In the lower respiratory tract, the virus affects the medium and small bronchi and bronchioles, causing inflammation, edema, and necrosis of the respiratory epithelium, which leads to the sloughing of necrotic material. These changes obstruct airflow, especially on expiration. Upon inspiration, the negative intrapleural pressure allows some air to pass the obstruction; however, during expiration, the positive pressure reduces the airway size, and causes further obstruction, prolonged expiration, and difficulty breathing. The child’s lungs hyperinflate, causing downward displacement of the spleen and liver. In addition, when the air trapped in the lungs is absorbed, areas of atelectasis may result.⁶ These events lead to arterial hypoxemia with oxygen saturations (SaO2) of less then 95% and, in cases of severe RSV, raised arterial carbon dioxide (PaCO2) levels. The child exhibits dyspnea, a rapid respiratory rate, and a reduced tidal volume.

After recovery, it has been postulated that RSV bronchiolitis may cause permanent changes in the lungs that may contribute to the development of asthma and chronic lung disease. Multiple studies point to RSV during infancy as a contributory factor to wheezing in childhood. It is unclear whether an episode of severe viral illness in infancy predisposes children to develop recurrent wheezing, or if those who contract bronchiolitis actually have an underlying condition that predisposes them to wheezing.⁴

What’s the verdict?

Nailing down the diagnosis of bronchiolitis is not a matter of extensive testing. History and clinical presentation are typically all that’s needed to make the call. According to 2006 Clinical Practice Guidelines developed by the American Academy of Pediatrics (AAP), clinicians should not routinely order laboratory and radiologic studies for diagnosis.

Although current evidence does not support routine radiography in children with bronchiolitis, a chest X-ray may be done to rule out other causes for the breathing trouble and may reveal hyperinflation and patchy atelectasis.³ Pulse oximetry is used on any infant with breathing difficulty, and if hypoxemia is suspected, arterial blood gases may be performed.

The knowledge gained from virologic testing for RSV rarely alters management decisions, although the results can be useful when cohorting patients is feasible.⁴ Diagnosis of RSV infection can be made by virus isolation, detection of viral antigens, detection of viral RNA, demonstration of a rise in serum antibodies, or a combination of these approaches. Many laboratories use antigen detection assays for rapid diagnosis of RSV. Two methods for collecting specimens are commonly used — nasal swab (NS) and nasopharyngeal aspirate (NPA). A recent study of 88 children, who had both NS and NPA performed during hospitalization for RSV revealed that the sensitivity of NPA was 97% while the sensitivity of NS was significantly lower at 67%.⁷ Although these diagnostic methods are available, it is rarely necessary to identify RSV when the child will be treated as an outpatient.

Evidence-based practice

Most of the children who contract RSV bronchiolitis develop mild to moderate symptoms and can be treated at home. These babies will need adequate fluids to prevent dehydration and may be given antipyretics to treat fever. Home management also requires a caregiver who can spot signs of a worsening condition — increasing respiratory rate, labored breathing, fewer wet diapers, or an overall worsening appearance.⁸ Inpatient treatment for the more severe cases includes oxygen therapy if the patient’s oxygen saturation consistently falls below 90%. Evidence suggests that the oxygen can be discontinued when the patient maintains 90%, is feeding well, and has minimal respiratory distress.⁴

No clinical benefit has been shown for chest physiotherapy in these patients.⁴ However, nasal suctioning may provide temporary relief of nasal congestion. IV fluids are provided when the patient cannot take sufficient oral fluids to prevent dehydration.

Other management strategies are not as commonly agreed upon. No consensus has been reached on the use of bronchodilators, antiviral therapy (ribavirin), or corticosteroids. While these pharmacologic treatments continue to be used, limited evidence has been gathered that these are effective in RSV bronchiolitis.⁸ For instance, since asthma presents with similar symptoms, albuterol has been used in children with bronchiolitis. However, several studies have shown no improvement in oxygenation or reduction in hospitalization rates with the use of albuterol.³ AAP Guidelines clearly recommend that bronchodilators should not be used routinely in the management of bronchiolitis.

As for antiviral therapy, the Agency for Healthcare Research and Quality (AHRQ), under its Evidence-Based Practice Program, has found sufficient data to reject, or at least doubt, the efficacy of aerosolized ribavirin. Study results on antiviral treatment in RSV bronchiolitis have been inconsistent and results have shown just marginal benefit in the face of cumbersome delivery methods and high cost.⁴

Although reports indicate that some 60% of infants hospitalized with bronchiolitis receive corticosteroids, no sufficient evidence supports their use.⁹ Because corticosteroids do not have the same beneficial respiratory effects in RSV bronchiolitis as they do in severe asthma, they are not recommended. In a nutshell, the AHRQ states that no single agent can be recommended for the treatment of bronchiolitis, and no treatment studied is superior to good supportive care.¹⁰ However there is substantial evidence that clinicians commonly use these interventions.

For high-risk infants, monthly prophylactic therapy during the RSV season has a role in preventing severe RSV bronchiolitis. Two FDA-approved drugs are available that provide temporary immunity protection against RSV. RSV-IVIG (RespiGam) and palivizumab (Synagis) have been shown to reduce the number of hospital admissions in high-risk pediatric patients.³ Palivizumab has been shown to reduce RSV hospitalizations as much as 78% and can be given in an outpatient setting as a monthly intramuscular injection.⁴

The 2006 Report of the Committee on Infectious Disease recommend the use of palivizumab prophylaxis for those younger than 24 months of age with chronic lung disease (CLD) who have required medical therapy for CLD within six months of the onset of RSV season. In some instances, premature babies without CLD are also candidates for this treatment. Due to the high cost of prophylaxis, experts agree that it should be reserved for infants who are at greatest risk of severe infection, including those with hemodynamically significant heart disease. While considering prevention strategies, it is vital to remember that handwashing is still the most important step in preventing the spread of RSV.

All the right advice

Informing the parents of high-risk infants about this potentially life-threatening illness and the available prophylactic treatment can prevent serious RSV disease. We need to teach parents about transmission and how to minimize the risks of contracting RSV. The highly contagious nature of this virus must be emphasized, especially if other children are in the home or children who might come in contact with caregivers. Although adults can acquire RSV infections, they are rarely as severe in healthy persons and usually mimic a cold or the flu. In contrast, the elderly and those who are immunocompromised or chronically ill may be at risk for severe RSV.

Rigorous handwashing following contact with the infected child is an essential first step to prevent transmission. The toys and eating utensils of the infected child also should not be shared with other children until they are washed.

Because most children who develop RSV are treated on an outpatient basis nurses need to teach basic therapeutic measures to caregivers, such as ensuring adequate fluid intake, using a cool mist vaporizer in the bedroom, and taking the child into a steamy bathroom for severe coughing episodes.

Because bronchiolitis is a relatively common disorder among children, nurses need a clear understanding of its pathophysiology, clinical presentation, diagnostic procedures, and management. In the cases of Sasha and Jimmy, their providers’ knowledge of current research enhanced their care and improved family education.

Back to our babies

Sasha had symptoms of a mild upper respiratory infection — runny nose and slight fever — without changes in appetite or signs of dehydration. Although she was alert and her respiratory rate was normal, she was wheezing. The NP diagnosed the child as having mild bronchiolitis, without dehydration or coexisting illness. The nurse advised fluids, humidification, and acetaminophen for fever. She also explained the usual course of the disease and what changes in Sasha’s condition would require immediate attention. Coretta brought her child back to the office the following day for follow-up. Sasha continued to improve and was completely free of symptoms two weeks later.

Jimmy was in worse shape though. He demonstrated signs of respiratory distress — rapid respirations, chest retractions, and flaring of the nares. He was diagnosed with moderate to severe bronchiolitis with dehydration. His pulse oximetry reading at rest was 92%. Jimmy was hospitalized for supportive care — monitoring, intravenous hydration, and oxygen. Fortunately, he improved and was discharged five days later.