Chapter e2: Management of Bronchopulmonary Dysplasia (BPD)

DISEASE/CONDITION(S)

Management of early (up to 1 postnatal [PN] week), evolving (>1 PN week to 36 weeks postmenstrual age [PMA]), and established (>36 weeks PMA) phases of bronchopulmonary dysplasia (BPD).

GUIDELINE/ OBJECTIVES

Suggest oxygen supplementation, ventilator strategies, pharmacological approaches, and nutritional support practice guidelines in all three phases of BPD.

BRIEF BACKGROUND

BPD is the most common chronic lung disease in infants. The status of the mode of respiratory support, with “physiologic” testing to ascertain the supplemental oxygen requirement, at 36 weeks PMA is the current recommended definition. Genetic predisposition plus interactions with environmental factors (lung immaturity, ventilator-induced lung injury, pre- and postnatal infections, and exposure to prolonged, high concentrations of supplemental oxygen) underlie the etiopathogenesis of BPD.

MAJOR RECOMMENDATIONS

Initiate nasal continuous positive airway pressure (NCPAP) in the delivery room (DR). Consider early surfactant administration, with early extubation to nasal intermittent positive pressure ventilation (NIPPV) and maintenance of noninvasive modes of respiratory support (NIPPV, NCPAP, and nasal cannula) in the early and evolving phases of BPD. Avoid hypoxia and hyperoxia in all three phases of BPD. Restrictive fluid intake with adequate energy intake are preferred in all three phases of BPD. Early treatment with caffeine is strongly recommended during the early and evolving phases of BPD. Diuretics may be used in the evolving and established phases of BPD. Prophylaxis against respiratory syncytial virus (RSV) is strongly recommended in the established phase of BPD.

PRACTICE OPTIONS

Practice Option #1: Ventilator Strategies

• Early phase: Avoid intubation; initiate support with NCPAP. If intubated, give “early” (<2h PN life) surfactant. Use short inspiratory times (0.3–0.4 s), rapid rates (40–60/min), low peak inspiratory pressure (PIP) (14–20 cm H₂O), moderate positive end expiratory pressure (PEEP) (4–6 cm H₂O), and low tidal volume (3–6 mL/kg) when on invasive mechanical ventilation. Extubate early to NIPPV. Blood gas targets: pH 7.25–7.35, PaO₂ 40–60 mmHg, and PaCO₂ 45–55 mmHg. High-frequency ventilation to be used for “rescue” if conventional ventilation fails.

• Evolving phase: Avoid endotracheal tube ventilation. Maximize noninvasive ventilation (NIPPV/NCPAP) for respiratory support. Blood gas targets: pH 7.25–7.35, PaO₂ 50–70 mmHg, and PaCO₂ 50–60 mmHg.

• Established phase: Older infants with severe BPD may require larger tidal volumes (10–12 mL/kg), with longer inspiratory times (>0.6 s), with slower rates (10–20 breaths/min). Blood gas targets: pH 7.25–7.35, PaO₂ 50–70 mmHg, and PaCO₂ 50–65 mmHg. Infants still requiring mechanical ventilation at 90–100 days of life or those with >5–7 failed extubation events should be considered as candidates for tracheostomy.

Practice Option #2: Oxygen Supplementation

• Early and evolving phases: Controversial, but generally alarm limits between 85 and 95% preferred; target SpO₂ 87–93%.

• Established phase: For prevention of pulmonary hypertension. SpO₂ alarm limit between 90 and 98% preferred; target SpO₂ 92–96%.

Practice Option #3: Pharmacotherapy

1. Caffeine: Use in early and evolving phases of BPD. Improves successful extubation rate; decreases BPD.

2. Vitamin A: Consider use in early and evolving phases. Dose is 5000 IU administered intramuscularly three times per week for the first 4 PN weeks. One additional infant survived without BPD for every 14–15 infants who received vitamin A.

3. Steroids: Evolving phase: Dexamethasone effective in weaning off mechanical ventilation when used “moderately early” and “delayed.” Established phase: Oral prednisolone may be helpful in weaning oxygen.

4. Diuretics: Evolving and established phases: Furosemide: may use daily or every other day with transient improvement in lung function. Spironolactone and thiazides: chronic therapy improves lung function, decreases oxygen requirements.

5. Beta agonists: Established phase: Transient relief with increased compliance and reduced pulmonary resistance. No significant effect on incidence or severity of BPD.

6. Anticholinergics: Established phase: Used in combination with beta agonists.

7. Fluids/Nutrition: Early, evolving, established phases: Restrictive (~140 cc/kg/day by PN day 7) fluid intake may decrease BPD. Increased energy intake (~110–120 Kcal/kg/day by PN day 7–10) may help with lung and body growth.

8. Immunization: Established phase: RSV prophylaxis and vaccination against influenza decreases incidence of rehospitalization and morbidity.

DESCRIPTION OF IMPLEMENTATION STRATEGY

Initiate NCPAP in the DR. If intubated in the DR, consider surfactant administration with early extubation to NIPPV. If supported on NCPAP in the neonatal intensive care unit (NICU), consider early (<2h of PN life) surfactant administration, with early extubation to NIPPV. Avoid hypoxia (SpO₂: <85%) and hyperoxia (SpO₂: >95%). Restrictive fluid intake (~140 cc/kg/day by PN day 7), with adequate energy intake (110–120 Kcal/kg/day by PN day 7–10) are preferred. Early treatment with caffeine is strongly recommended.

QUALITY METRICS

Maintenance of noninvasive respiratory support, targeting SpO₂ with acceptable limits avoiding hypoxemia and hyperoxemia, and monitoring growth (head, length, and weight) parameters.

“Gentle” invasive/noninvasive approaches to ventilation with judicious exposure to oxygen supplementation along with early/selective surfactant use in conjunction with specific pharmacotherapy and nutritional support form the basis of the management of BPD.