What is the current consensus on using diuretics in infants with bronchopulmonary dysplasia who have persistent pulmonary edema or fluid overload?

Diuretics in Bronchopulmonary Dysplasia: Current Consensus

The American Thoracic Society recommends against the routine use of diuretics in infants, children, and adolescents with post-prematurity respiratory disease (PPRD) and BPD, and suggests judicious discontinuation of chronic diuretic therapy for infants discharged from the NICU on these medications. 1

Evidence Quality and Limitations

The confidence in diuretic efficacy for BPD is very low, with critical limitations in the available evidence 1:

• Most studies were conducted between 1983-1992, before widespread surfactant use, examining "old BPD" characterized by airway injury and parenchymal fibrosis rather than the current phenotype of disrupted alveolarization 1
• No study has demonstrated an association between diuretic use and reductions in BPD incidence, duration of mechanical ventilation, or NICU length of stay 1
• Studies enrolled few patients (largest included only 43 infants) and focused on short-term pathophysiological parameters rather than clinically important outcomes 1, 2
• Evidence is considered indirect, with incomplete outcome data, lack of intention-to-treat analysis, and restriction to infants with limited comorbidities 1

When Diuretics May Be Considered

Despite the recommendation against routine use, diuretics may have a limited role in specific clinical scenarios:

For signs of right heart failure associated with pulmonary hypertension, loop diuretics, thiazides, or spironolactone should be used cautiously 3. This represents supportive therapy rather than primary treatment, as the American College of Cardiology emphasizes aggressively treating underlying lung disease before initiating pulmonary vasodilator therapy 3.

Short-term physiological improvements have been documented 1, 4, 5:

• Furosemide therapy for 7-8 days improved dynamic pulmonary compliance and airway resistance, and decreased FiO2 requirements 1
• Lung ultrasound studies show decreased pulmonary edema severity scores and improved oxygenation during the first week of diuretic treatment 4
• Oral thiazide-spironolactone combination improved lung compliance over 4 weeks 5

Significant Complications and Risks

The risks of diuretic therapy are substantial and well-documented 1, 5:

• Nephrolithiasis and metabolic bone disease, particularly with furosemide 1
• Electrolyte abnormalities: Potassium and phosphorus depletion are potential complications requiring monitoring 5
• Decreased calcium excretion with associated concerns for nephrocalcinosis 5
• Metabolic alkalosis and dehydration 1
• Ototoxicity with prolonged use 1
• Impaired weight gain, which is critical in premature infants 1

Practice Variation and Lack of Long-Term Benefit

There is marked institutional variation in diuretic prescribing patterns, with the percentage of infants receiving courses >5 days ranging from 4% to 86% across hospitals 6. This variation persists even after adjusting for patient characteristics, highlighting the lack of evidence-based consensus 6.

Critically, diuretic use does not reduce the duration of home oxygen therapy 7. In a cohort of 154 infants with BPD discharged on home oxygen, those exposed to diuretics had significantly longer hospital length of stay but no difference in duration of home oxygen therapy compared to unexposed infants 7.

Practical Approach for Infants Discharged on Diuretics

For infants already receiving chronic diuretic therapy at NICU discharge, discontinuation should proceed in a judicious manner 1. This means:

• Avoid abrupt cessation without clinical assessment
• Monitor for signs of worsening pulmonary edema or increased work of breathing during weaning
• Recognize that many infants are discharged on diuretics despite uncertain utility in post-NICU care 1
• Base weaning decisions on documented clinical stability rather than arbitrary timelines 3

Common Pitfalls to Avoid

Do not continue diuretics indefinitely without reassessing clinical necessity 1. The lack of evidence for long-term benefit, combined with significant potential complications, argues against prolonged maintenance therapy in the absence of specific indications like symptomatic pulmonary hypertension with right heart failure 1, 3.

Do not use diuretics as a substitute for optimizing underlying lung disease management, including appropriate oxygen saturation targets (92-95%), minimizing ventilator-induced lung injury, and addressing contributing factors like aspiration or structural airway abnormalities 8, 3.