Chronic Lung Disease of Prematurity (Bronchopulmonary Dysplasia – BPD)

00:01 In this talk we’re going to focus on pulmonary disease in the newborns.

00:07 And it makes sense to start right off the bat with chronic lung disease of prematurity, which is also called bronchopulmonary dysplasia.

00:16 Bronchopulmonary dysplasia or chronic lung disease of prematurity is a condition that’s common in infants who are born prematurely.

00:25 It starts as a neonatal respiratory distress soon after birth.

00:30 It then is worsened by a subsequent respiratory support.

00:35 So, the pressure that we’re using to ventilate these children is actually worsening their long-term disease.

00:43 It’s defined as any child who has an oxygen requirement after 28 days of life or over 36 weeks corrected.

00:53 In other words, if you are born at 32 weeks, when you are four weeks old, you are 36 weeks corrected.

01:02 It’s more common in premature babies.

01:05 So the more premature you are, the more likely you’ll get chronic lung disease of prematurity.

01:11 Here’s an example of a graph you might see in any hospital where they’re delivering children.

01:16 You’ll notice if you’re born at less than 24 weeks, only a tiny percentage of those infants are going to end up completely normal.

01:25 A substantial percentage, perhaps 15% of them, will end up with chronic lung disease, and the majority will actually pass away before being able to leave the NICU.

01:36 Flipside, when you’re born at 32 weeks, the vast majority of children are born completely healthy with a tiny percentage getting chronic lung disease and very few fatalities.

01:45 And this is about a typical picture of what it looks like right now in the United States.

01:51 This curve is moving to the slides left.

01:55 In other words, more and more of those very young children are having better and better outcomes as a result of research that actively is taking place in these infants across the United States.

02:07 So risk factors for chronic lung disease of prematurity include at a baseline surfactant deficiency and we’ll talk about that a little bit separately.

02:16 Children who have hyperoxia who are requiring high amounts of oxygen are at increased risk for developing other problems, such as retinopathy of prematurity.

02:27 Infants who have prolonged mechanical ventilation with high pressures through their endotracheal tube are at increased risk for developing more severe chronic lung disease of prematurity.

02:38 The actual mechanical action of ventilating them is actually hurting their lungs.

02:45 Also, neonates and NICU patients with poor nutrition are at increased risk for developing chronic lung disease of prematurity.

02:54 So how do you diagnose this? Well, it’s a clinical and a historical diagnosis primarily.

03:00 Typically, it’s a very premature infant who’s had respiratory distress early on in their life.

03:06 Lab findings are consistent with chronic lung disease.

03:10 So for example, on a Chem 7 you might see a high bicarbonate as the kidneys are accommodating their respiratory acidosis.

03:19 They’re creating a metabolic alkalosis through renal function that’s counteracting that so that the child maintains a decent pH.

03:29 Patients may be on Lasix with this illness because it helps to dry out those lungs and let the pulmonary mechanics work a little better, and so, for patients who are on Lasix, when we get that Chem 7, we will often see a low chloride, a low potassium.

03:44 The chest X-ray may show diffused haziness, as is pictured here, with low lung volumes, and this is classic for chronic lung disease.

03:55 The treatment of chronic lung disease involves respiratory support with as minimal settings as possible.

04:03 We’re going to do something in the NICU which we call permissive hypercarbia.

04:07 It’s not at all unusual to allow a child to have a carbonate level of around 55 as opposed to 40, which is normal, to allow the child to be a little bit acidotic from a respiratory standpoint because that will allow us to back off on the settings and cause less damage to the lungs.

04:28 Sometimes neonatologists will switch up the method which they intubate -- Rather ventilate children in that they’ll use an oscillator, which has very quick respirations, very fast at a fixed pressure as opposed to wild fluctuations in pressures with the goal of reducing some of that damage.

04:47 We’ll treat these patients with diuretics like Lasix to keep those lungs clear to allow for better gas exchange.

04:54 And if these patients are severely ill, we’ll give corticosteroids keeping in mind that there are some evidence that administration of corticosteroids may negatively impact IQ later on down the line.

05:07 So there can be complications of chronic lung disease of prematurity that we should be aware of.

05:12 Specifically, these children may go on to develop pulmonary hypertension and often are followed by a cardiologist where they’re watching those right ventricular sizes and pressures.

05:22 They may develop congestive heart failure and that has to be treated accordingly with medications.

05:27 They may develop recurrent pulmonary infections, so these patients are at more risk for viral illnesses like bronchiolitis and at more risk for bacterial infections like pneumonia.

05:39 Later on in childhood and even into adulthood, they are at increased risk for asthma.

05:44 And for the very severely premature, they’re at risk for streptococcal infections like pneumonia and they will put these children on palivizumab.

05:53 Palivizumab is falling out of favor as we’re realizing that it’s not particularly cost-effective and you may see that going out of style.

06:02 Palivizumab, remember, is an antibody against RSV, and so it prevents RSV infection.