Lung Diseases

Question 1

3 Main Pediatric Lung Diseases

Answer 1

Respiratory Distress Syndrome (RDS)
Sudden Infant Death Syndrome (SIDS)
Cystic Fibrosis (CF)

Question 2

What is another name for RDS?

Answer 2

Hyaline membrane disease

Question 3

Define RDS

Answer 3

Lung disease in a preterm infant resulting from insufficient surfactant

Question 4

What is the major cause of morbidity & mortality in infants born prior to 30 weeks gestation?

Answer 4

RDS

Question 5

What product has changed clinical course & decreased morbidity & mortality rates in RDS?

Answer 5

Exogenous surfactant

Question 6

Epidemiology of RDS

Answer 6

Incidence decreases over 35 weeks
More severe in male infants
More severe & common in white infants

Question 7

Increased Incidence Risk Factors of RDS

Answer 7

Low gestation
Male sex
White race
Maternal DM (decreased lung development & surfactant production)
C-section pre-onset of labor
Perinatal asphyxia
Maternal HTN

Question 8

Decreased Incidence Risk Factors of RDS

Answer 8

Prolonged rupture of membranes
Chronic congenital infections
Maternal substance abuse
Antenatal corticosteroid exposure

Question 9

2 Major Issues in RDS

Answer 9

Immature lungs

Lack of surfactant

Question 10

Reasons for Immature Lungs

Answer 10

Born before lung development

Born before surfactant production

Question 11

At what stage can true gas exchange occur?

Answer 11

Saccular stage

Alveolar ducts present

Question 12

Reasons for Lack of Surfactant

Answer 12

Production begins at 23-24 weeks

Adequate amounts not produced until 35 weeks

Question 13

What does surfactant do?

Answer 13

Reduces surface tension in alveoli
Facilitates lung expansion
Prevents alveolar collapse

Question 14

Other Issues in RDS

Answer 14

Excessively compliant chest walls
Weakness of respiratory muscles
Alveolar collapse

Question 15

Pathophysiology of RDS

Answer 15

Alveolar collapse alters V/Q
Pulmonary shunting
Arterial hypoxemia
Metabolic acidosis
Vasoconstriction
Pulmonary HTN
May have R to L shunting
Increased pulmonary blood flow
Pulmonary edema

Question 16

How do the lungs appear in hyaline membrane disease?

Answer 16

Solid & congested with diffuse atelectasis

Question 17

What are hyaline membranes made from?

Answer 17

Plasma proteins leaked from damaged capillaries

Question 18

PE findings in RDS

Answer 18

Progressive tachypnea
Retractions
Grunting
Cyanosis
Decreased breath sounds

Question 19

Diagnostics of RDS

Answer 19

CXR

ABGs

Question 20

Findings with CXR in RDS

Answer 20

Increased density of lung fields
Reticulogranular infiltrates
Air bronchograms
Elevation of diaphragm

Question 21

ABG Findings in RDS

Answer 21

Hypoxemia
Hypercarbia
Metabolic acidosis

Question 22

How does exogenous surfactant drastically change the course of RDS?

Answer 22

Decreased need for oxygen
Decreased mechanical ventilation
Reduce incidence of gas leaks

Question 23

What needs to be done for babies with RDS?

Answer 23

Stabilization
Cardiopulmonary function monitoring
Adequate respiratory support
Proper thermal, metabolic, & nutritional support

Question 24

Prevention of RDS

Answer 24

Prevention of premature delivery

Antenatal corticosteroids

Question 25

What do antenatal corticosteroids do?

Answer 25

Improve lung compliance Increase lung volume Decrease capillary protein leak

Question 26

Complications of RDS

Answer 26

``` Hemorrhagic pulmonary edema Capillary rupture & interstitial fluid May be seen with exogenous surfactant First 5-7 days of life Rapidly fatal ```

Question 27

Define SIDS

Answer 27

Sudden unexpected death of an infant less than 1 year of age, with onset of the fatal episode apparently occurring during sleep, that remains unexplained after a thorough investigation, including a complete autopsy & review of the circumstances of death & clinical history

Question 28

Age and time of death in SIDS

Answer 28

Sparing in 1st month Increases in 2nd month Peak incidence at 3 months Occurs during the night

Question 29

Possible Maternal Risk Factors for SIDS

Answer 29

``` Young age Multiparity Smoking & drug abuse during pregnancy Previous fetal deaths Anemia during pregnancy Placenta previa Premature rupture of membranes Low social class Low family income Short inter-pregnancy interval Unmarried mother Partner unemployed Late attendance of antenatal clinic Postnatal depression Attendance to psychiatrist UTI in pregnancy ```

Question 30

Possible Infantile Risk Factors in SIDS

Answer 30

``` Male Low birth weight Premature Blood type B Low APGAR scores Low hematocrit @ 48 hours Not using a pacifier Prone/side sleeper Bed-sharing Overheating Formula fed Siblings in family Sleeping in own room Previous SIDS in family Previous cyanotic episode ```

Question 31

What is the most important preventable risk factor for SIDS?

Answer 31

Maternal smoking

Question 32

Risks to child from maternal smoking include

Answer 32

Fetal hypoxemia Inhibition of airway growth and development Decreased ability to arouse to noxious stimuli Increased susceptibility to respiratory tract infections

Question 33

How do pacifiers help to prevent SIDS?

Answer 33

Reduce arousal threshold | No evidence to discourage pacifier use

Question 34

Why is a prone position a risk to develop hypercapnia?

Answer 34

Rebreathing of expired air Hypoxemia Upper airway closure Arousal deficit

Question 35

Pathology of SIDS

Answer 35

Intrathoracic petechial hemorrhages Frothy secretions around mouth & nose Evidence of URI Hypoxic tissue markers Abnormalities in brain stem serotoninergic system

Question 36

Monitored events of SIDS have shown

Answer 36

Apnea, bradycardia, unlikely primary mechanism No arousal reaction Gasping occurs in majority of victems

Question 37

Prevention of SIDS

Answer 37

``` Supine sleeping Firm sleep surface Soft objects out of crib Don't sleep with infant Smoke-free environment Pacifier at nap & bedtime Avoid overheating ```

Question 38

Define Cystic Fibrosis

Answer 38

Syndrome of chronic sinopulmonary infections, malabsorption & nutritional abnormalities

Question 39

Organ Dysfunction in CF

Answer 39

``` Sinuses: sinusitis, nasal polyps Lungs: endobronchitis, bronchiectasis Pancreas: exocrine insufficiency, CF DM Intestine: meconium ileus, constipation Liver: focal sclerosis Vas Deferans: failure to develop Sweat gland: salt-losing dehydration ```

Question 40

CF Related Complications

Answer 40

``` Stunting, wasting Micronutrient deficiencies Steatorrhea Intestinal obstruction Intussusception Hypoelectrolytemia Airway infection Progressive obstructive lung disease Bronchiectasis DM Rectal prolapse Sinusitis Vasculitis Non-alcoholic steatohepatitis Male infertility ```

Question 41

Genetics of CF

Answer 41

Large gene on chromosome 7 Carrier rate high Autosomal recessive

Question 42

Diagnostics of CF

Answer 42

One or more symptoms Positive "newborn screen" CFTR dysfunction- sweat chloride Emphasis on the process

Question 43

"End Stage" Lung Disease in CF

Answer 43

Bronchiectasis Infection Inflammation Mucous plugging

Question 44

Physiologic Abnormalities in CF

Answer 44

Severe airflow obstruction | Increased RV, FRC

Question 45

Treatment for CF

Answer 45

``` Airway clearance therapy Antibiotics Inhaled mucolytics Bronchodilators Enzyme replacement Fat soluble vitamins Azithromycin Ibuprofen ```