Atrial and Brain Natriuretic Peptides in Bronchiolitis
Condition: Bronchiolitis
MeSH terms: Bronchiolitis
Study type: Observational

Summary: 
      The purpose of this study is to collect information about what happens to certain chemicals
      produced in the body called hormones during respiratory infections such as bronchiolitis.
      Bronchiolitis is an infection of small airways in the lungs caused by a virus. This
      infection, which causes swelling and injury in the lungs, is commonly seen in infants and
      children less than 2 years of age.
    

Detailed description: 
      Intravascular volume and serum osmolality are tightly regulated by a balance of various
      neurohumoral mediators. In critical illness, these regulatory mediators may be modified by
      disease or treatment, either benefiting or harming the patient. Such regulatory mediators of
      intravascular volume and fluid balance include atrial natriuretic peptide (ANP), brain
      natriuretic peptide (BNP) and vasopressin (also called antidiuretic hormone-ADH). Although
      well studied in adult cardiac patients, these neurohormones have not been investigated in
      pediatric respiratory diseases such as bronchiolitis, a common cause of admission to the
      Pediatric Intensive Care Unit (PICU). Understanding the effects of pediatric respiratory
      diseases and treatment interventions on the concentrations of these neurohormonal regulators
      such as ANP and BNP is a crucial first step in formulating more effective fluid therapy. For
      example, some patients with bronchiolitis have elevated ADH levels. Increased ADH
      concentration predisposes to fluid retention and increases the risk of pulmonary edema. Since
      ANP and BNP antagonize the action of ADH, simultaneous measurement of all three hormones may
      help elucidate the mechanisms of fluid balance in bronchiolitis.

      The study hypothesis is that the plasma concentrations of ANP and BNP in infants and children
      with bronchiolitis are inversely associated with ADH concentration and lung hyperinflation.
      Furthermore, plasma concentrations of ANP and BNP in bronchiolitis are associated directly
      with increased oxygen requirement and positive fluid balance. The significance of this study
      is to better understand the relationship between various neurohormones that regulate
      intravascular fluid volume in patients with respiratory failure and bronchiolitis. The
      understanding of this complex relationship has the potential to improve fluid/diuretic
      therapy and patient outcome with severe respiratory distress in the future.

      We plan to enroll 100 patients in this study. The population will be infants and children
      between 37 weeks and 2 years of age (corrected for gestational age). 50 patients with
      bronchiolitis will be enrolled to collect ANP, BNP, and ADH plasma levels along with serum
      osmolality and urine osmolality for up to 5 consecutive days in Shands Children's Hospital.

      Comparison: 50 control patients will be enrolled to record normal baseline plasma ANP, BNP,
      and ADH at the time of admission in Shands Hospital surgical center at the University of
      Florida.
    

Observational model: Cohort
Time perspective: Prospective
Sampling method: Probability Sample
Study population: 
        Children between the ages of 37 weeks and 2 years old with evidence of bronchiolitis.
      
Keywords: Bronchiolitis; ANP; BNP; Atrial Natriuretic Peptide; Brain Natriuretic Peptide; Vasopressin; ADH; Pediatric; Respiratory Distress; Fluid Balance