Neonatal Respiratory Distress Syndrome

Question 1

Which neonates are more likely to get Respiratory Distress Syndrome (RDS)

Answer 1

Less than 36 weeks gestational age

Question 2

What is the pathophysiology of RDS

Answer 2

Pulmonary surfactant deficiency: inadequate surfactant will require higher inspiratory pressures to re-expand alveoli and achieve gas exchange

Question 3

What are the roles of pulmonary surfactant

Answer 3

Decreases surface tension forces at air:fluid interface at alveoli, prevents alveolar collapse (atelactasis), facilitates clearance of pulmonary fluid

Question 4

Why are neonates less than 36 weeks more likely to acquire RDS

Answer 4

Endogenous cortisol stimulates synthesis and secretion of pulmonary surfactant at 30-32 weeks of gestation and sufficient amounts are not reached until 36 weeks of gestation

Question 5

What is the increased risk risk factors

Answer 5

Prematurity, gestational diabetes, C-section without labor, male gender

Question 6

What are the decreased risk risk factors

Answer 6

Maternal hypertension, maternal narcotic addition, cardiovascular disease

Question 7

What are the sequence of events caused by diminished surfactant

Answer 7

Progressive atelectasis -> hypoventilation -> increased partial carbon dioxide/decreased oxygen/low pH -> hypotension -> pulmonary vasoconstriction -> alveolar hypoperfusion

Question 8

What is the clinical presentation of a patient with RDS, when would this be seen

Answer 8

Tachypnea, hypoxemia, hypercapnia, within the first six hours of life

Question 9

Who is RDS diagnosed

Answer 9

X-ray findings (diffuse reticulogranular pattern)

Question 10

What is the medication used to treat RDS, how does it alleviate the problem

Answer 10

Antenatal glucocorticoids: increases production fibroblast neumocyte factor, stimulates biosynthesis of surfactant in type II pneumocytes

Question 11

What are the atenatal glucoroticoids given

Answer 11

Betamethasone 12 mg IM every 24 hours for 2 doses OR dexamethasone 6mg IM every 12 hours for 4 doses

Question 12

What are the categories of drugs that are given to prevent premature delivery and allow for the steroids to start working

Answer 12

Beta-adnergic agonists, magnesium sulfate, prostaglandin inhibitors, calcium channel blockers

Question 13

What is the beta-adnergic agonist used to prevent premature delivery

Answer 13

Terbutaline (No longer used due to adverse effects)

Question 14

What is the MOA of magnesium for preventing premature delivery, what concentration does the magnesium sulfate need to be at

Answer 14

Inhibiting voltage- independent calcium channels at myometrial cell surface, 4-8 mg/dL (loading dose IV then continuous infusion)

Question 15

What are the adverse effects of magnesium sulfate in the mother, in the neonate

Answer 15

Mother: N/V, flushing, headache, blurred vision, pulmonary edema, shortness of breath, chest pains

Neonate: respiratory depression, slow GI function (also has neonatal neuroprotection)

Question 16

What is used in conjunction with magnesium to prevent preterm delivery, when can it ONLY BE TAKEN

Answer 16

Indomethacin, gestation age LESS THAN 30 weeks

Question 17

What is the only CCB that can be used to prevent premature delivery. adeverse effects

Answer 17

Nifedipine, headache, tachycardia, palpatations

Question 18

If a patient has RDS what can be done for supportive care to aid in breathing, what is this to prevent

Answer 18

Supplemental O2, CPAP, mechanical ventillation/ respiratory and metabolic acidosis

Question 19

What is a common problem for patients with RDS, how can this be prevented

Answer 19

Pulmonary Edema, 120-130 ml/kg/day

Question 20

When would diuretic be used in a patient with RDS, which diuretic would be used, what is the largest con with doing this

Answer 20

Reserved for neonates with pulmonary edema OR cannot be removed from the ventilator, furosemide 1-2 mg/kg/day in 1-2 divided doses, increases the ductus arterious opening

Question 21

What is adequate nutrion for patients with RDS, empiric antibiotic therapy to prevent what

Answer 21

100-110 kcal/kg/day/ ampicillin and gentamicin to prevent sepsis

Question 22

What is the major surface-active component of human surfactant, most important proteins for human surfactant for patients with RDS and why

Answer 22

DPPC or lecithin/ SP-B and SP-C: enhances spreadability and surface adsorption leading to DECREASED SURFACE TENSION

Question 23

What are the three FDA approved surfactant products for treatment and prevention of RDS

Answer 23

Beractant: 100 mg/kg PL , calfactant: 105 mg/kg PL, poractant: 200 mg/kg PL

Question 24

What are the natural surfactants, ones used for prevention and treatment, treatment only

Answer 24

Calfactant and Poractant, calfactant and Beractant/ Poractant

Question 25

T/F: Patients must be intubated in order to recieve natural surfactants

Answer 25

True

Question 26

What are the therapeutic effects of natural surfactants

Answer 26

Decreased supplemental oxygen and mechanical ventilation, decreased incidence of pneumothorax and PIE, increase survival by 40% regardless of birth weight or gestation age, reduce mortality of RDS by 50%

Question 27

What is the benefits of using the natural surfactants (calfactant and poractant), what is a significant improvement of poractant

Answer 27

Longer duration of effect (dosed every 12 hours), faster weaning from the ventilator, less supplemental oxygen required/ lower incidence or mortality and re-dosing

Question 28

When is it best to use surfactants in patients with RDS

Answer 28

Early therapy: given within two hours of life, Rescue therapy: once the patient is diagnosed

Question 29

How is it known a patient needs a 2nd dose of surfactant

Answer 29

Intubated infant requiring FIO2 greater than or equal to 30% to maintain arterial PaO2 greater than or equal to 50 mmHg or oxygen saturation greater than 90%

Question 30

What are the monitoring parameters of giving surfactants

Answer 30

heart rate, oxygen saturation, arterial blood gas

Question 31

What are the adverse effects of giving surfactants

Answer 31

oxygen desaturation, transient bradycardia, mucous plugging, increased risk of pulmonary hemmorrhage and apnea