Respiratory newborns

Question 1

Causes of respiratory distress in newborn term infant?

Answer 1

PULMONARY:
Most common-transient tachypnea newborn
Meconium aspiration
Pneumonia
Resp.distress syndrome
Pneumothorax
Pulm.HT

(Rare) Diag.hernia, tracheo-oesopha fistula, Pulm. hypoplasia, obstruction,..

NON PULMONARY: 
Congenital HD
Encepalopathy
Anemia severe
Met. acidosis

Question 2

Symptoms of respiratory distress in newborn?

Answer 2

Tachypnea >60
Laboured breathing: nasal flaring, chest wall indrawing
Expiratory grunting
Cyanosis (if severe)

Question 3

TTT caused by? and risk factors

Answer 3

Delay in reabsorption of lung liquid, particularly in C section
- usually settles within 1st day - a few days if more severe

Risk factors :

Elective cesarean section delivery
Male sex
Macrosomia
Excessive maternal sedation
Prolonged labor
Fluid overload to the mother, especially with oxytocin infusion

Question 4

MAS- meconium aspiration syndrome probable causes?

Answer 4

Increases with gestational age
Acute or chronic hypoxia and/or infection can result in the passage of meconium in utero.

Vagal stimulation and distress can cause passage of meconium in utero.

Gasping (because asphyxiated in utero) can cause aspiration of amniotic fluid contaminated by meconium.

Question 5

MAS- meconium aspiration syndrome consequences on lungs?

Answer 5

Meconium aspiration before or during birth can cause airway obstruction, chemical pneumonia, therefore severe respiratory distress.

Specifics:

• Areas of complete obstruction-atelactasis
• Areas of partial obstr.- air leakage because air can’t escape on expiration
• ->pneumothorax
• Chemical pneumonitis
• Inhibition surfactant
• Hypertrophy of pulm.art so persistent pulm. HT –>can lead to R-L shunt–>hypoxemia

Question 6

MAS- meconium aspiration syndrome happens mostly in which situations?

Answer 6

Postterm pregnancy.
Abnormal fetal heart rate and biophysical profile. 
Thick meconium.
Preeclampsia.
Maternal hypertension.
Maternal diabetes mellitus.
Intrauterine growth retardation.
Oligohydramnios.
Maternal heavy smoking, chronic respiratory or cardiovascular disease.

Question 7

MAS diagnostic tests

Answer 7

During labour: monitor, aminoiinfusion

Observation after: if infant vigorous, routine care/ if depressed, inspect larynx, consider intubation
Blood gas levels
Xray

Oxygen therapy
Assisted ventilation
Medications
Antibiotics
Surfactant

Question 8

What does Xray for MAS look like?

Answer 8

Diffuse, assymetric patchy infiltrates.
Areas of consolidation and hyperinflation
Pneumothrax may be present

Question 9

Pneumonia in newborns age onsets:

Answer 9

Early onset 48h-1week
-congenital

Late onset (3 weeks of age)

Question 10

What causes early onset Pneumonia

Answer 10

Bacteria: usually ascending birth canal into amniotic fluid
Strep B,A (b-hemolytic)
Listeria monocytogenes
E.coli
Staph.Aureus
H.Influenzae
Strep.pneumoniae (alpha-hemolytic)
Chlamydia

Viral: usually through maternal placenta
RSV
CMV
HSV
HIV

Question 11

What are risk factors for newborn Pneumonia

Answer 11

Chorioamnionitis
Premature or prolonged ROP
Maternal fever
Strep B colonization vagina
STD mother/child
Intrauterine asphyxia

Question 12

Late onset pneumonia: cause?

Answer 12

Usually in environment of neonate: nosocomial infections (klebsiella, pseudomonas, E.coli) ,catheters (staph.epidermidis)

Question 13

Symptoms of pneumonia in newborn?

Answer 13

Respiratory distress (laboured breathing,nasal flair, tachypnea,cough, apnea, cyanosis, jaundice, vomiting, hypo/hyperthermia)

Question 14

RDS- resp distress syndrome (hyaline membrane disease): what is it?

Answer 14

Caused by deficiency of surfactant:

• leads to widespread collapse
• inadequate gas exchange

Question 15

RDS risk factors:

Answer 15

-more severe in boys
-prematurity
diabetic mother

Question 16

TT of RDS antenatally and post-natally

Answer 16

Antenatal: GC to mother
Newborn: surfactant natural (tracheal tube)
Ambient O2 +/- +ve pressure,
+/-artificial ventilation
Blood gas monitor
Breathing movements

Question 17

Apnea of newborn what is it?

Answer 17

> 20s absence of gas flow

<20s if bradycardia too

Question 18

Apnea of newborn most common in?

Answer 18

Preterm infants <1500g

Question 19

Physiological mechanisms behind newborn apnea

Answer 19

Sleep related: premies sleep 80% time
CO2: premies need higher PaC02 to stimulate resp.
Hypoxia: premie goes tachypneic then apneic if hypoxic
Immature central NS: decrease CO2 sensitivity

Question 20

Types apnea:

Answer 20

Central (CNS), Obstructive, mixed

Question 21

Other causes of apnea (not related to respiration)

Answer 21

Hypo/hyperthermia
Hypoglycemia
Hyponatremia
Sepsis
Anemia
Intra-ventric.hemmorhage (not good progn.)
NEC
Maternal drug withdrawal (Magnesium)

Question 22

TT apnea:

Answer 22

Caffeine (best, least dangerous)
Oxygen therapy (MONITOR 02 LEVELS)
CPAP (just air +ve pressure on airway)