2b Respiratory Diseases (CLD) Yen

Question 1

What is an overview of Chronic Lung Disease (CLD)?

Answer 1

Also known as Bronchopulmonary Dysplasia (BPD). Important cause of respiratory illness in preterm infants. Major contributor to the morbidity and mortality seen with preterm infants. Overall incidence is 15% for preterm infants < 1,250g birth weight

Question 2

What are the current definitions of CLD?

Answer 2

Oxygen requirement at 28 postnatal days. Oxygen requirement at 36 weeks post conceptual age

Question 3

What is the pathogenesis (multifactoral) of CLD?

Answer 3

Inflammation (Lung is most vulnerable at the sacular stage of development (31-34 weeks gestation). Release of reactive oxygen radicals can damage lung structures). Oxygen toxicity (cellular damage from reactive oxygen metabolites and free radicals. Preterm infants have inadequate antioxidant defenses). Mechanical injury (Volutrauma from overdistended airways and airspaces. Barotrauma from increased pressures required)

Question 4

What is the pathology of CLD?

Answer 4

Findings noted at autopsy of infants with CLD: Disruption of lung development, Alveolar hypoplasia, Reduced microvascular development, Airway injury, Inflammation, Parenchymal fibrosis

Question 5

What are the signs and symptoms of CLD?

Answer 5

Radiographic findings. Abnormal pulmonary function. Pulmonary edema. Airway hyperreactivity. Airway inflammation. Chronic lung injury

Question 6

What is used for CLD prevention?

Answer 6

Antenatal Corticosteroids (ACS): Decreases risk of RDS, but does not decrease incidence of CLD (d/t increased survival). Fluid Restriction: May reduce pulmonary edema and potentially minimize lung injury, fluids should be adjusted to maintain neutral or slightly negative water balance. Vitamin A

Question 7

Why is Vitamin A used for CLD prevention?

Answer 7

Vitamin A deficiency causes impaired lung healing, reduced alveolar number, increased loss of cilia, increased susceptibility to infection. Preterm infants born deficient in Vitamin A stores. May help as an antioxidant

Question 8

How is Vitamin A dosed?

Answer 8

5,000 IU IM 3x week for 4 weeks

Question 9

What is used for management of CLD?

Answer 9

Mechanical Ventilation. Nutrition. Fluid restriction. Diuretics

Question 10

What is Mechanical Ventilation like for CLD management?

Answer 10

Use lowest possible pressures to maintain acceptable CO2. Deliver supplemental O2 to prevent hypoxia. Wean gradually

Question 11

What is Nutrition like for CLD management?

Answer 11

May need up to 150 kcal/kg/day. Ensures recovery, growth, extra demands from increased work of breathing

Question 12

What is Fluid restriction like for CLD management?

Answer 12

Avoid pulmonary edema. Modest restriction is 140-150 ml/kg/day. Severe restriction is 110-120 ml/kg/day

Question 13

What is Diuretic use like for CLD management?

Answer 13

Acutely improves pulmonary mechanics/oxygenation. Little evidence to support their long term use

Question 14

What are the diuretics used for CLD?

Answer 14

Furosemide. Chlorothiazide

Question 15

What are the Bronchodilators used for CLD?

Answer 15

Albuterol. Ipratropium

Question 16

What are the basic characteristics of Albuterol use with CLD?

Answer 16

Impacts survival, severity of CLD and duration of ventilatory support. Use based on management of children with asthma. Administered as MDI or nebulization (no difference). MDI may be more effective

Question 17

What are the side effects with Albuterol use?

Answer 17

Tachycardia, arrhythmias, tremor, hypokalemia and irritable behavior. Monitor for heart rates > 180 bpm

Question 18

What is Ipratropium use like for CLD?

Answer 18

Acute episodes of bronchospasm. Combination with albuterol for more effective bronchodilation

Question 19

What are the side effects with Ipratropium?

Answer 19

Tachycardia, blurred vision, eye pain, dry mouth. Caution in patients with narrow angle glaucoma. Caution with those with peanut allergy

Question 20

What are corticosteroids like for CLD?

Answer 20

Reduces inflammation and improves lung function. Reduces need for mechanical ventilation. Can be given inhaled or systemically. Systemic use associated with serious side effects (cerebral palsy)

Question 21

What does APP recommend for corticosteroid use in CLD?

Answer 21

Restrictive use of systemic steroids. Most often used for patients with severe CLD who cannot be weaned from maximal ventilatory and oxygen support. Dexamethasone must be used in low doses and duration. Inhaled steroids based on treatment of children with asthma

Question 22

What is the outcome like with CLD?

Answer 22

Most infants are mildly affected and usually do well. Severe CLD increases risk of abnormal pulmonary function, neurodevelopment and growth. In severe CLD, lung function remains abnormal during the first year. Infection prevention with vaccinations (influenza, RSV) should be employed