Bronchopulmonary dysplasia (BPD), also known as chronic lung disease (CLD), is a major complication of premature birth and is associated with a significant increased risk of complications including death. Diuretics have been used for decades in babies with BPD and are considered a standard of care. Patients receive electrolyte supplementation to replace the electrolytes removed by the diuretics. Spironolactone is not as good as other diuretics at removing extra fluid, but it is different from chlorothiazide and furosemide because instead of removing potassium, it actually can increase potassium levels in our body. Spironolactone is used with chlorothiazide to try to minimize the potassium lost; therefore, reduce the electrolyte supplementation needed. However, studies have suggested that preterm babies aren´t developed enough to appropriately respond to spironolactone. Also, one study has shown that adding spironolactone to chlorothiazide in patients with BPD has no effect on whether or not patients receive electrolyte supplementation. This study will examine whether there is a difference in the amount of electrolyte supplementation between patients receiving chlorothiazide only or chlorothiazide plus spironolactone. the investigators hypothesize there will be no difference in the amount of electrolyte supplementation between the two groups.

Brief Title

Determining the Effect of Spironolactone on Electrolyte Supplementation in Preterm Infants With Chronic Lung Disease

Official Title

Determining the Effect of Spironolactone on Electrolyte Supplementation in Preterm Infants With Chronic Lung Disease

Brief Summary

Bronchopulmonary dysplasia (BPD), also known as chronic lung disease (CLD), is a major<br /> complication of premature birth and is associated with a significant increased risk of<br /> complications including death. Diuretics have been used for decades in babies with BPD and<br /> are considered a standard of care. Patients receive electrolyte supplementation to replace<br /> the electrolytes removed by the diuretics. Spironolactone is not as good as other diuretics<br /> at removing extra fluid, but it is different from chlorothiazide and furosemide because<br /> instead of removing potassium, it actually can increase potassium levels in our body.<br /> Spironolactone is used with chlorothiazide to try to minimize the potassium lost; therefore,<br /> reduce the electrolyte supplementation needed. However, studies have suggested that preterm<br /> babies aren´t developed enough to appropriately respond to spironolactone. Also, one study<br /> has shown that adding spironolactone to chlorothiazide in patients with BPD has no effect on<br /> whether or not patients receive electrolyte supplementation. This study will examine whether<br /> there is a difference in the amount of electrolyte supplementation between patients receiving<br /> chlorothiazide only or chlorothiazide plus spironolactone. the investigators hypothesize<br /> there will be no difference in the amount of electrolyte supplementation between the two<br /> groups.

Detailed Description

Bronchopulmonary dysplasia (BPD), also known as chronic lung disease (CLD), is a major
complication of premature birth and is associated with significant morbidity and mortality.
Bronchopulmonary dysplasia most commonly affects preterm infants who have required prolonged
aggressive mechanical ventilation and/or oxygen supplementation. Risk factors associated with
BPD include degree of prematurity, infection, mechanical ventilation, oxygen concentration,
and nutritional status. Despite significant advances in the care of preterm infants and
improved survival, the incidence of BPD has been fairly static over the past decade.

Diuretics and fluid restriction are considered a mainstay of therapy in the management of BPD
to combat interstitial alveolar edema. Short courses of furosemide followed by long-term
therapy using a thiazide diuretic with concurrent spironolactone have shown improvement in
pulmonary function and better outcomes. Double-blinded, randomized, placebo-controlled trials
have shown improvement in pulmonary compliance, airway resistance, infants alive at
discharge, and a decrease in fraction of inspired oxygen and need for furosemide boluses.

Spironolactone is a competitive aldosterone receptor antagonist that acts on the distal
convoluted tubule and collecting duct to facilitate sodium excretion while conserving
potassium and hydrogen ions. Since only a minimal amount of sodium filtered by the glomerulus
reaches the distal tubule, spironolactone is considered a weak diuretic. Spironolactone is
primarily used with chlorothiazide for its potassium-sparing effect to reduce the need for
electrolyte supplementation. There has only been one prospective, randomized, double-blind,
placebo-controlled study comparing chlorothiazide with or without the addition of
spironolactone in premature infants with chronic lung disease. This study demonstrated no
difference between the groups in the need for electrolyte supplementation, electrolyte
balance, or pulmonary function. In addition, preterm infants' distal tubules may respond
inadequately to aldosterone; thereby, limiting the role of spironolactone in this patient
population.

In the neonatal population, spironolactone is primarily used in addition with chlorothiazide
for its potassium-sparing effects to reduce the need for electrolyte supplementation.
However, evidence and current practice suggests the majority of patients still receive
electrolyte supplementation. One study evaluated spironolactone's effect on the need for
electrolyte supplementation, but there is no published data with a primary outcome evaluating
spironolactone's effect on the quantity of electrolyte supplementation. We hypothesize there
will be no difference in the amount of electrolyte supplementation between the two groups.

Outcome Measures

Outcome measures are the tests that investigators perform to prove whether or not a treatment being tested in a clinical trial is having any effect.

Inclusion Criteria:

  -  The attending makes the decision to start enteral chlorothiazide for long-term
     diuretic therapy.

  -  Gestational age < 32 weeks at time of delivery

  -  If patient is currently receiving furosemide and electrolyte supplements, these must
     be discontinued prior to enrollment.

Exclusion Criteria:

  -  Renal anomaly

  -  Receiving maintenance IV fluids for more than the previous 48 hours

  -  Any contraindication to receiving enteral medication

  -  Serum Na < 132 mEq/L

  -  Serum K < 3.0 mEq/L

  -  Serum Cl < 92 mEq/L

  -  Presence of ostomy of any sort