Utility of Continuous Pulse Oximetry for Pediatric Patients With Stable Respiratory Illness

Respiratory illnesses are among the most common causes for inpatient pediatric hospitalizations every year. The most common respiratory illnesses that make up these hospitalizations include pneumonia, acute bronchiolitis, and asthma.

Pneumonia is one of the top three illnesses requiring pediatric hospitalization and is a significant cause or morbidity and mortality. The incidence of pediatric pneumonia varies depending on the country and age group, but worldwide the annual incidence in children younger than five years of age is 150 million and approximately 2 million pediatric deaths, per year, are attributed to pneumonia. Therefore, it is important to understand this disease and how it impacts pediatric hospital admissions.

Pneumonia is defined as an acute infection of the lung parenchyma secondary to an infectious etiology such as viruses or bacteria. When an infectious organism is present, the defense mechanisms of the body, including the lungs, are disturbed and the resultant inflammation gives rise to parenchymal damage. Symptoms can include fever, cough, and shortness of breath. Findings on imaging can demonstrate infiltrates in the lungs. Vital sign testing can show elevations in a child's heart rate and decreases in the amount of oxygen present in the blood (pulse oximetry) secondary to the infiltrative processes in the lungs.

Pneumonia is the most common serious infection in the pediatric population and accounts for up to 1-4% of all pediatric Emergency Department (ED) visits in the United States (US). Furthermore, of the pediatric patients that present to the ED with pneumonia, 20-25% are admitted to the inpatient pediatric unit for further management. This decision to admit a child to the hospital depends on various underlying factors including age, medical conditions, and severity of illness. One of the factors that is considered when deciding whether to admit a child to the hospital for pneumonia is oxygen saturation, or the amount of oxygen in the blood.

Bronchiolitis is another common respiratory illness in the pediatric population and is estimated to account for up to 100,000 US hospital admissions annually. There is a seasonality with most infections occurring in the fall and winter months. It is the leading cause of hospitalization in infants and young children with most cases involving children less than two years of age.

Acute bronchiolitis refers to lower airway inflammation and obstruction secondary to a viral infection. When a virus infects the terminal bronchiolar epithelial cells of the lower airways in the lungs, damage to these cells results and subsequently causes cellular sloughing and inflammation. This inflammation, coupled with mucous build-up, accounts for the obstruction that is seen in acute bronchiolitis. Symptoms include rhinitis, congestion, cough, tachypnea, wheezing, and accessory muscle use. Like pneumonia, hypoxemia (decreased oxygen content in the blood) can occur with acute bronchiolitis with the most severe complication being acute respiratory failure requiring mechanical ventilation.

The third most common respiratory illness that accounts for pediatric hospital admissions is asthma. Asthma affects 1 in 12 children in the US and is a leading cause of ED visits. It is the most common chronic disease in childhood in developed countries and an estimated 8.3% of children in the US had been diagnosed with asthma in 2016.

Asthma is a complex, multifactorial, immune-mediated disease and is defined by episodic and reversible airway constriction and inflammation. Triggers for asthma exacerbations can include infections, environmental allergens, and other irritants. Smooth muscle constriction in the airways and inflammation/edema result in intermittent and reversible lower airway obstructions. Symptoms of asthma include cough, wheezing, shortness of breath, and chest tightness. Like the other respiratory illnesses mentioned, asthma can also result in hypoxemia.

Respiratory illnesses, including pneumonia, acute bronchiolitis, and pneumonia pose a significant threat to the pediatric population and are major causes of morbidity and mortality throughout the world. In the US, most pediatric hospital admissions are secondary to these illnesses and determining how to best monitor and manage these patients while in the hospital is important. Specifically, the most ideal technique to monitor for hypoxemia is one of current debate.

Currently, there are two main ways to monitor for hypoxemia in a hospital setting. The first is to have a pediatric patient on continuous monitoring, which involves the child being continuously connected to a monitor that displays various vital signs, one of which being oxygen saturation (SpO2). This technique has been studied over the last several years and many concerns have been raised regarding alarm fatigue, or the phenomenon that occurs when a patient is continuously connected to a monitor and the monitor alarms an overwhelming amount. One study found that this form of monitoring was used in up to 50% of children in non-ICU settings and that up to 99% of the alarms did not require clinical action. In fact, this study found that more than 10,000 alarms can occur in a pediatric unit in 1 week and that greater than 150 alarms can occur on any one patient each day. Furthermore, while these continuous monitors are meant to identify patients who are deteriorating, it has been suggested that the efficacy is limited by alarm fatigue and that evidence has not shown them to improve patient outcomes. Finally, a recent study also demonstrated that the second form of monitoring, scheduled vital checks, may be superior to electronic measurements when assessing patients for deterioration. Currently, there are no guidelines to recommend what form of monitoring, continuous monitoring or scheduled vital checks, is superior and studies evaluating the rationale behind widespread continuous monitoring techniques are lacking.

This study will determine if there is a difference in hospital length of stay between pediatric patients admitted for uncomplicated respiratory illnesses receiving continuous hardwire cardiorespiratory monitoring and those receiving intermittent vital signs measurements. Patients will be randomized to two groups. One group will be comprised of patients receiving continuous hardwire monitoring during the entire stay in the hospital. The other group will be comprised of patients receiving intermittent vital signs measurements (heart rate, respiratory rate, blood pressure, oxygen saturation, and temperature) every four hours, per standard of care on the pediatric unit.

Data will be collected on supplemental oxygen use and patients' level of oxygen saturation throughout the hospital stay. On day of hospital discharge, up to 14 days, parents or guardians will be asked to complete the Parent Study Questionnaire, to assess parental rating of the level of care their child received in hospitalization and parental comfort level with continuing to care for their child at home.