The Respiratory System and Acute Causes of Distress in the Newborn

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Respiratory Diseases of
the Newborn
Beth Mogensen, RRT-NPS
1
OBJECTIVES
1. Provide overview of respiratory system of
the newborn
2. Identify non-respiratory causes of
distress in the newborn
3. Review respiratory diseases/ anomalies
of the newborn
2
3
Early Development
4
Fetal Lung Development
Week 4: the laryngotracheal groove forms
on the floor foregut
Week 5: the left and right lung buds push
into the pericardioperitoneal canals
(primordial of pleural cavity)
Week 6: the descent of heart and lungs
into the thorax. Pleuroperitoneal foramen
closes
5
6
Fetal Lung Development
Week 7: the lung buds divide into
secondary and tertiary bronchi
Week 24: the bronchi divide 14 more
times and the respiratory bronchioles
develop
By birth, there will be an additional 7
divisions of bronchi
7
Fetal Lung Histology
STAGE 1: Pseudoglandular Period (517 weeks) all the major elements of the
lungs have formed except for those
involved with gas exchange
STAGE 2: Canalicular Period (16-25
weeks) bronchi and terminal bronchioles
increase in lumen size and the lungs
become vascularized
8
Fetal Lung Histology
STAGE 3: Terminal Sac Period (24
weeks to birth) more terminal sacs
develop and interface with capillaries
lined with Type I alveolar cells or
pneumocytes
--Also have Type II pneumocytes which
secrete surfactant thereby decreasing
the surface tension forces and aids in
expansion of the terminal sacs
9
STAGE 4:
Alveolar Period
(late fetal period to
8 years) 95% of
mature alveoli
develop after birth.
A newborn has
only 1/6 to 1/8 of
the adult number
of alveoli and
lungs appear
denser on x-ray
10
Respiratory Distress at Birth
Rule of 6: non respiratory causes of distress
S&S
Hypothermia/
Hyperthermia
Hypovolemia
Hyoptension
Hypoglycemia
Anemia
Polycythemia
transfusion
Diagnosis
- check temperature
- obtain prenatal history
- measure blood pressure
- blood glucose measurement
- measure hematocrit
- measure hematocrit
Management
- heat or cool as
necessary
- gingerly give volume
- give volume and/or
vasopressor
- give glucose
- transfuse with PRBC
- partial exchange
(lower Hct)
11
Respiratory Distress in the
Newborn
Transient Tachypnea of the Newborn
(TTN)
Surfactant Deficiency (HMD,RDS)
Meconium Aspiration Syndrome (MAS)
Pneumonia/ Sepsis
Pneumothorax or other air leaks
12
Respiratory Distress in the
Newborn
Respiratory Causes
Congenital Abnormalities of the Lung/Thorax



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
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Congenital Heart Disease (CHD)
Congenital Diaphragmatic Hernia (CDH)
Congenital Cystic Adenomatiod Malformation (CCAM)
Tracheal Abnormalities
Esophageal Atresia
Pulmonary Hypoplasia
Persistent Pulmonary Hypertension of the
Newborn (PPHN)
13
What do you need to know
to Figure out the Cause…
Maternal History

Any risk factors
Gestational age of Infant
Amniotic fluid (color/odor/volume)
Intrapartum history
Clinical Presentation/ Assessment
X-Rays
Lab Evaluations
14
Clinical Presentation
Respiratory Assessment


Respiratory rate
Quality
Shallow
Deep
Nasal Flaring
Grunting
Retractions
Breath Sounds
15
Clinical Presentation
Color—pink, dusky, pale, mottled


Central
Peripherally
Heart rate
Pulses

Distal vs Central
Perfusion


Capillary Refill Time (CRT)
Blood Pressure
16
Clinical Presentation
Physical characteristics

Flat nasal bridge, Simian crease, recessed chin, low
set ears
Deformities

Extra digits, gastroschesis, imperforate anus
Muscular

Hyoptonia vs Hypertonia
Skeleton

Choanal Atresia, Osteogenesis Imperfecta
Other

Scaphoid abdomen, heart tones on Right side
17
X-Ray
Structures




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
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
Ribs
Vertebra
Liver
Stomach/ intestine
Lungs
Heart
Trachea
Esophagus
18
X-Ray
Lungs



Lung Volume
Expansion
Densities
Fluid/ collapse (atelectasis)>>white
Free Air>>dark
Mass
Heart shape and size


Boot shaped
Egg or Oval shaped
19
Lab Values
CBC with diff
ABG/CBG/VBG
Blood Cultures
CRP
Electrolytes
Type and Cross
PKU
20
Respiratory Distress
Determining Differential Diagnosis
What you need to know…
•
•
•
•
History
Presentation/ clinical assessment
X-rays
Lab values
21
Transient Tachypnea of the
Newborn (TTN)
Most common diagnosis of respiratory
distress in the newborn
Remember often “term infants” may be a
little early
Ineffective clearance of amniotic fluid from
lungs with delivery
Most often seen at birth or shortly after
22
Transient Tachypnea of the
Newborn
History







Common with C-Section delivery
Maternal analgesia
Maternal anesthesia during labor
Maternal fluid administration
Maternal asthma, diabetes, bleeding
Perinatal asphyxia
Prolapsed cord
23
TTN presents:
Respiratory Assessment
Tachypnea 60-150 bpm
 Nasal flaring
 Grunting
 Retracting
 Fine Rales
 Cyanotic

24
TTN
X-Ray findings



Prominent Perihilar streaking
Hyperinflation
Fluid in fissure
Labs


CBC within normal limits
ABG/CBG showing mild to moderate
hypercapnia, hypoxemia with a respiratory
acidosis
25
TTN
26
TTN
Have delayed reabsorption of fetal lung
fluid which eventually will clear over
several hours to days
Treatment: Treat signs and symptoms.
Support infant, may need O2, is probably
too tachypneic to PO feed so start IV fluids
Be patient!!
27
Surfactant Deficiency
(RDS, HMD)
One of the most common problems
associated with a premature infant
Decreased surfactant production in lungs
of pre-term infants
With decreased surfactant production,
alveoli collapse, become atelectatic,
yielding poor lung function and increasing
signs of respiratory distress
28
RDS
History


Gestational age < 38 weeks
Prenatal care
Diabetes (controlled vs uncontrolled)
Perinatal infection

Problems during pregnancy/delivery
Asphyxia
Stress to fetus
Hypothyroidism

Multiple births
29
RDS presents:
Respiratory Assessment








Tachypnea > 60 bpm
Nasal flaring
Grunting
Retracting
Apnea/ irregular respiratory pattern
Rales (crackles)
Diminished breath sounds
Cyanosis
30
RDS
X-Ray
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Loss of volume
Reticulogranular pattern or “ground glass”
appearance
Air bronchograms
Bell shaped thorax
Air leak, PIE
Loss of heart borders/ atelectasis
White out
31
RDS
32
33
RDS
34
RDS
Laboratory Results

ABG/CBG
Hypoxia
Hypercarbia
Acidosis

CBC with Differential/ HHP
Used to rule out other causes of respiratory
distress

Always check electrolytes, especially
glucose, potassium and calcium
35
Treatment for RDS
Post-Exogenous Surfactant
Therapy

Many on the market
Prophylactic Treatment

Administered in the delivery room
Rescue Treatment

Given after a definitive diagnosis of RDS
36
MECONIUM ASPIRATION
SYNDROME
Most often found in post date infants > 40
weeks, but may occur in infants >34 weeks
Infant passes meconium due to varying degrees
of asphyxia in utero
Obstruction of large and small airways with
aspirated meconium
Aspiration may occur:



in utero
intrapartum
postpartum period
37
MAS
History
Prenatal Care
Maternal diabetes
Pregnancy Induced Hypertension (PIH)
Pre-eclampsia
Problems during pregnancy/delivery
Color of amniotic fluid
38
MAS
Respiratory Assessment

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Tachypnea
Nasal flaring
Grunting
Retracting
Apnea/ irregular respiratory pattern
Decreased breath sounds/ wet/ rhonchi
39
MAS
Clinical Assessment

Color
Pale/gray
Cyanotic
Stained skin
X-Ray




Increased AP diameter
Hyperinflation
Atelectasis
Pneumothorax
40
MAS
41
MAS
42
Pneumonia/ Sepsis
Occurs frequently in newborns
3 types



Congenital Pneumonia
Intrapartum Pneumonia
Postnatal Pneumonia
Most often seen with chorioamnionitis,
prematurity and meconium aspiration
Get thorough history
43
Causes
Prematurity
Prolonged rupture of membranes
Maternal temp > 38C
Foul smelling amniotic fluid
Nonreassuring stress test
Fetal tachycardia
Meconium
Maternal hx of STDs
44
Respiratory Assessment
Tachypnea
Apnea, irregular breathing pattern
Grunting
Retractions
Nasal flaring
Colorful secretions
Rales, rhonchi
Cyanosis
45
Clinical Assessment
Gray, pale color
Lethargy
Temperature instability
Skin rash-pettechia
Tachycardia
Glucose issues
Hypoperfusion
Oliguria
46
X-Ray
Patchy infiltrates (aspiration)
Bilateral diffuse granular pattern
Streaky
Loss of volume
Densities
47
Pneumonia/ Sepsis
48
Pneumothorax and other
Air Leaks
History



What happened in the delivery room?
Was positive pressure given?
Large amount of negative pressure generated
with the 1st breath?
49
Pneumothorax/ Air Leaks
Respiratory Assessment


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Tachypnea
Nasal flaring
Grunting
Retractions
BS absent or decreased
50
Pneumothorax/ Air Leak
Clinical Assessment



Cyanotic
Pale, gray
Heart Rate
Tachycardia
Bradycardia
PEA

Pulses
Normal
Poor
absent
51
Pneumothorax/ Air Leak
Perfusion


Capillary Refill (CRT)
Blood Pressure if monitoring Arterial Line,
narrowing pulse pressure
Deformities of Chest Wall

Asymmetry of chest
CHEST X-Ray speaks for itself!!
52
Pneumothorax
53
Pneumothorax
Right lateral decubitus view of
pneumothorax
54
Pneumopericardium
55
Congenital Abnormalities of the
Lung and Thorax
Congenital Heart Disease (CHD)
Congenital Diaphragmatic Hernia (CDH)
Congenital Cystic Adenomatiod
Malformation
Tracheal Abnormalities
Esophageal Atresia
Pulmonary Hypoplasia
56
Congenital Heart Disease
Defect present at birth- often picked up on
early ultrasound
Increased risks:

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Parents have CHD?
Siblings have CHD?
Maternal diabetes
Exposure to German measles, toxoplasmosis,
or if mother HIV+
Alcohol use during pregnancy
Cocaine use during pregnancy
57
CHD
Two types of CHD

Acyanotic-blood returning to Right side of
heart passes thru lungs—usually defect in
heart wall, or obstructed valve or artery
Pink baby
Sats within normal limits

Cyanotic-have a mixing of oxygenated blood
with venous blood—shunting ductus, PFO,
ASD, VSD
Blue baby
Low sats
58
CHD
Respiratory Assessment

Respirations
Normal
Tachypnea

Saturations depend upon defect.
Acyanotic lesions sats are more normal
Cyanotic lesions acceptable sats are low
~ 70% is acceptable; ideally on 21% FiO2
59
CHD
Clinical Assessment

HR
Slow, fast, variable
murmur

BP
Check in all 4 extremities



Pulses in all extremities
CRT in all 4 extremities
Color
Acyanotic -pink
Cyanotic-blue
60
CHD
Labs and Tests


ABGs—dependent upon defect
Lactic Acid
Chest X-Ray


Heart shape and size
Pulmonary blood flow
Echocardiogram

Best test to aid in diagnosis
Cardiac Cath for possible intervention
61
Congenital Diaphragmatic Hernia
Congenital Cystic Adenomatoid
Malformation
Ideally diagnosed in utero
Develops during pseudoglandular stage,
but CCAM can form up to 35 weeks
Normally compromised at delivery
requiring immediate intubation
CDH more commonly found on Left side
62
CDH
63
Congenital Diaphragmatic
Hernia
64
CDH/ CCAM
Respiratory Assessment


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Tachypneic
Retractions
Nasal flaring
Grunting
Breath Sounds
Decreased on the affected side
May hear bowel sounds in chest with CDH
65
CDH
Clinical Assessment


Scaphoid Abdomen- classic sign
Color
Cyanotic

Heart Rate
Fast, slow or normal

Perfusion
Depends upon the severity

X-Ray—Best diagnostic tool
Bowel, stomach, liver in chest

ABGs
Acidosis, hypoxemia and hypercarbia
66
Left Congenital Diaphragmatic
Hernia
67
CCAM
68
Persistent Pulmonary
Hypertension (PPHN)
Pulmonary hypertension resulting in
severe hypoxemia secondary to R>L shunt
thru PFO and/or PDA
Usually affecting term or near-term infants
May be extremely difficult to manage
If not responding to available therapy
consider transporting to an ECMO center
69
Fetal Circulation
70
PPHN
History





Meconium?
Asphyxia?
Stress?
Pneumonia/ Sepsis
Primary Pulmonary Hypertension
Dysfunction in pulmonary endothelial vasodilating
mechanism

CDH/ CCAM
71
PPHN
Respiratory Assessment




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Tachypnea
Retractions
Grunting
Nasal flaring
Breath Sounds
Depend on cause

Pre and Post-ductal saturations to monitor
shunting- best indicator if ECHO not available
72
PPHN
Clinical Assessment

Color
Blue/ gray

X-Ray
Depends on cause
Usually with decreased blood flow, minimal lung markings

Lab
Dependent on cause
Many present with abnormal Platelets/ PT/ Fibrinogen

ABG
Respiratory and metabolic acidosis
73
Airway Abnormalities
Occur less frequently than pulmonary
parenchymal diseases
Presentation is often quite dramatic with
significant respiratory distress
Stridor may be an important key to
diagnosing the abnormality
74
Airway Abnormalities
Supraglottic




Nose-Choanal Atresia
Craniofacial-Pierre Robin
Macroglossia-Down’s
Tumors-Hemangioma
Glottic


Vocal Cord Paralysis
Tumors and Cysts
Hemangioma, Cystic Hygroma, Teratoma
Tracheal Esophageal Fistula/ Atresia
Webs
Trauma
75
Cystic Hygroma
76
Tracheal Esophageal Fistula/
Esophageal Atresia
77
Airway Abnormalities
Subglottic



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Stenosis—congenital or acquired
Webs
Atresia
Tumors
Trachea
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


Tracheomalacia
Stenosis
Cyst
Atresia
Extrinsic


Vascular Ring
Mediastinal Mass
78
History/ Presentation
Circumstances surrounding onset of symptoms
Speed of progression of symptoms
Position of comfort and how change affects
symptoms
Presence of feeding abnormalities
Nature of cry
Previous infection
History of previous intubation or trauma
Presence of associated cardiopulmonary
abnormalities
79
Airway Abnormalities
Respiratory Assessment



Tachypnea
Retractions
Work of Breathing
Breath Sounds

Stridor is the MOST important physical sign
created by airway turbulence and indicates
obstruction
Inspiratory—implies supraglottic or glottic
Expiratory—implies intrathoracic airway
Mixed—implies subglottic
80
Airway Abnormalities
Clinical Assessment

Heart Rate
Tachycardia
Bradycardia when obstructed

Color
Cyanotic



Lethargy
Irritability
Feeding Difficulty
81
Airway Abnormalities
Bronchoscopy used for evaluating
abnormality
“Tools” for Treatment:

Dependent upon Diagnosis
Prone patient
Oral Airway
N-P Tube
Steroids
Meds for reflux
OG, NG, NJ or G-Tube feedings
82
Airway Abnormalities

Possible Surgical Interventions
Cricoid Split
Tracheostomy
Excise Hygroma
Place stents
83
Scenario
Baby Boy S



No prenatal care. Uneventful delivery vaginal
delivery. APGARS 8 and 9 at 1 and 5
minutes, respectively.
Infant taken to newborn nursery and given
routine care. Eyes and thighs done, bath
completed. VSS. Looking good and smelling
nice.
Infant went out to mother to breast feed and
you have been summoned to “check on
baby”.
84
Scenario
Upon arriving in the mother’s room, you
begin assessing infant.
Baby’s color is rather blue.
Tachypneic—RR 70s to 80s
Bulb sx and get a little bit of colostrum.
Retractions and Grunting present
Baby’s temp is 35.9
What will you do?
85
Scenario
1. Take infant back to nursery for observation
and monitoring.
2. Place infant on O2 if sat < 90-92 depending
upon your policy.
3. Place infant under radiant warmer.
4. Obtain a full set of vital signs.
1.
2.
3.
4.
RR 80s—Retracting, nasal flaring, grunting
HR 180—with murmur
BP 42/30 with MAP 36
SaO2 on 100% blow by 88%
86
Scenario


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5. Color—dusky
6. CRT 4 seconds
7. Poor peripheral pulses
87
Scenario
CALL MD if you haven’t already…
Continually reassess infant.
With your next assessment: VS have not
changed much. Infant continues to grunt,
retract and have nasal flaring. Sats 86.
88
Scenario
When auscultating, you notice that the
heart tones are now more midline than on
left. You also notice that when
auscultating the left lung that you thought
you heard gas bubbles…
What do you want to do?
What do you suspect this infant has?
89
Scenario
STAT CXR
Intubate infant and ventilate
Place large bore Anderson/ Replogle tube
to continuous low suction
Give fluid bolus (and more if needed)
Probably start pressors
Do what needs to be done to stabilize this
infant and call for transport…
90
Take Away…
Don’t be afraid to “think out of the box”
We continually see “funky” things
Do no harm… this is someone’s baby
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