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Respiratory Distress in Newborn
Dr L S DeshmukhDM ( Neonatology )
Professor and Head,
Dept. of Pediatrics
Govt. Medical College,
Aurangabad
Respiratory distress
• Cause of significant morbidity and
mortality
• Incidence 4 to 6% of live births
• Many are preventable
• Early recognition, timely referral,
appropriate treatment essential
Respiratory distress
• RR > 60/ min
• Retractions
• Grunt
• + Cyanosis
Note : RR should be recorded in a quiet state for at least one minute.
RD IN NB - Causes Pulmonary
- Parenchymal
- Extraparenchymal
Non Pulmonary
- Heart
- Metabolic
- Brain
- Blood
- Abdominal
RD in Newborn – Causes
Pulmonary
Parenchymal Extraparenchymal
* RDS (HMD) * Upper airway obstruction
* TTN (RDS II) (Cloanal atresia, stenosis)
* Aspiration (Blood * Pneumothorax
meconium) * Pleural effusion
* PPHN * Cong. Diaph. hernia
* Pneumonia * Diaphragmatic paralysis
* Pulm. hemorrhage
* Pulm. hypoplasia
RD in Newborn – Causes
Extrapulmonary
Heart Metabolic Brain Blood Abdominal
- CCF - Met. Acidosis - Haemorrhage - Hypovolemia - NEC
- PDA - Hypoglycemia - Edema - Hyperviscosity - Pneumo
- CCHD - Hypothermia - Drugs - Acute blood peritonium
- Vascular - Sepsis - Pain loss - Large
mass
Surgical causes of respiratory distress
• Tracheo-esophageal fistula
• Diaphragmatic hernia
• Lobar emphysema
• Pierre -Robin syndrome
• Choanal atresia
Approach to respiratory distress
History
• Onset of distress
• Gestation
• Antenatal history / steroids
• Predisposing factors- PROM, fever
• Meconium stained amniotic fluid
• Asphyxia
Mathai ss et al ,MJAFI 2007; 63 : 269-272
Preterm - Possible etiology
Early progressive - Respiratory distress
syndrome or hyaline
membrane disease (HMD)
Early transient - Asphyxia, metabolic causes, hypothermia
Anytime - Pneumonia
Term – Possible etiology
Early well looking - TTNB, polycythemia
Early severe distress - MAS, asphyxia,
malformations
Late sick with - Cardiac
hepatomegaly
Late sick with shock - Acidosis
Anytime - Pneumonia
RR
(bpm
Aspiration cong. Pneumonia, sev. HMD CDH
cardiac malformation
Approx. 6 Hours of age
Normal
60
Course of Neonatal Tachypnoea : Etiologic possibilities
Source : Baurn DJ, Birth Risks, Nastle Nutrition Workshop, 1993
TTNB
HMD
Evaluation of RD in NB – Clinical History
Antenatal History Most likely association
* Prematurity, IDMs * HMD
* PROM, maternal fever, * Pneumonia
Unclean vaginal exams,
UTI, diarrhoea
* Asphyxia/MSAF * Aspiration
* Caesarean delivery * TTN
* Polyhydramnios * Pulm. Hypoplasia
* Oligohydramnios * TE fistula, CDH
* H/o receiving steroids * RDS less
* Traumatic/breech delivery * ICH / Phrenic nerve paralysis
Evaluation of RD in NB – Clinical History
When did the symptoms begin?
Best historical assistant
Stridor at birth – Cong. Anomaly
After increase feed volum. – GEF & aspiration
After intubation – tube block, air leak
After extubation – Trauma / atelectasis
Evaluation of RD in NB – Clinical History
Is the disorder new / chronic / recurrent?
Chronic disorder – BPD
Recurrent disorders
- Aspiration pneumonia
- Pulmonary hemorrhage
- Lobar atelectasis
Evaluation of RD in NB – Clinical History
Does the NB have spontaneous cough?
Spont. Cough, always abnormal in NB
Causes of cough in NB : CRADLE
C cystic fibrosis
R respiratory infection
A aspiration (reflux, TE fistula)
D dyskinesia of cilia
L lung, airway, vascular malformation
E edema (heart failure, BPD)
Fletcher MA, 1998, Physical diagnosis in neonatology
Approach to respiratory distress
Examination
• Severity of respiratory distress
• Neurological status
• Blood pressure, CFT
• Hepatomegaly
• Cyanosis
• Features of sepsis
• Look for malformations
Evaluation of RD in NB – Downes’ Score
0 1 2
Cyanosis None In room air In 40% FiO2
Retractions None Mild Severe
Grunting None Audible with
stetho.
Audible without
stetho.
Air entry C;ear Decreased Barely audible
RR Under 60 60-80 Over 80 or
apnea
Score : > 4 = Clinical respiratory distress; monitor ABG
> 8 = Impending respiratory failure
Evaluation of RD in NB – RR
Affected by various conditions
Low rates – Decreased MV
High rates – Wasted ventilation
Rapid & shallow – Stiff lungs (RDS)
Slow & Deep – Increased resistance (MAS)
Isolated tachypnoea – Acidosis, sepsis, CCF
Evaluation of RD in NB – Grunting
Classical in HMD, may be seen in
pneumonia, pulmonary edema & others.
Expiration through partially closed glottis.
Intermittent / continuous (Severity)
Generates CDP of 2-3 cms H2O
Maintains FRC
Evaluation of RD in NB – Cyanosis
Total desat. Hb > 3.5 gm/dl
Central cyanosis – always abnormal
Acrocyanosis – May be normal
Hyperoxia test – Pulm. Vs Cardiac
Anemia / Polycythemia - Falacious
Hyperoxia test
test Method result diagnosis
Hyperoxia 100 % fio2 5-10
min
Pao2 increases
to > 100 torr
Pao2 increases
by < 20 torr
Parenchymal
lung disease
PPHN / CCHD
Hyperoxia-hypervetilation
MV 100 % fio2
& VR 100-150 /
min
Pao2 increases
to > 100 torr
w HV
Pao2 increases
at critical Pco2
No increase in
Pao2 with HV
Parenchymal
lung disease
PPHN
CCHD
Evaluation of RD in NB – Physical Exam.
Look for :
- Shrill cry / abn. tone (CNS disorder)
- Persistent frothing at mouth (TE fistula)
- Cyanosis, relieved on crying (choanal atresia)
- Seaphoid abd. (CDH)
- Single umbilical astery (CHD)
- Meconium staining of skin, nails or cord (MAS)
Evaluation of RD in NB – Retractions
Site of
retraction
Probable
region affected
Likely clinical association
Intercostal Pulmonary
parenchyma or
distal airway
Conditions of decreased
parenchymal compliance
MHD, TTN, Pneumonia
Subcostal Insertion of
diaphragm
Mild degree of retraction
are normal in neonates;
Airway obstruction or
parenchymal disease; in
the absence of intercostal
retractions, indicates
proximal airway obstruction
Evaluation of RD in NB – Retractions
Site of
retraction
Probable region
affected
Likely clinical association
Unilateral
subcostal
Decreased
movement of
opposite diaphragm
Isolated phrenic nerve weakness
Brachial palsy
Massive pleural effusion
Tension pneumothorax,
CDH
Suprasternal Obstruction in
upper airway
Choanal atresia or stenosis
Laryngeal stenosis or malacia
Obstruction of upper airway due
to secretions, edema
Sternal Sternal compliance
greater than pulm.
compliance
Proximal airway obstruction
Clinical Examination
Color—pink, dusky, pale, mottled
– Central
– Peripherally
Heart rate
Pulses
– Distal vs Central
Perfusion
– Capillary Refill Time (CRT)
– Blood Pressure
Clinical Examination
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, hepatomegaly, situs inversus
Suspect surgical cause
• Obvious malformation
• Scaphoid abdomen
• Frothing
• History of aspiration
Evaluation of RD in NB – Chest Exam.
Increased A-P diameter of chest
- Pneumothorax, emphysema or CDH
Asymmetric chest movement
- Tension pneumothorax, pleural effusion, CDH, Diaphragmatic paralysis, PIE.
Auscultation
- Breath sounds ,
- Early, coarse crackles – Pneumonia & HMD
- Late crackles - PIE
Wheezing – BPD, GER, Vascular rings, bronchomalacia
Auscultatory percussion – Lobar atelectasis, effusion.
Transillumination of the chest
RD in Newborn – Clinical Differences
Symptoms &
signs
Pulm.
disorder
CVS
disorder
CNS
disorder
Metabolic
disorder
Tachypnea + + + or apnea +
I/C Recession +++ ± - ±
Expiratory
grunt
+ - - -
Cyanosis + ++++ + -
Hepatomegaly + +++ - -
History Prematurity,
MSL,
PROM,
Polyhydram.
Rubella,
hydrops LFD
Breech
Hypotonia
birth asphyxia
Preterm
increase
protein intake
Seizures Rare Absent May occur Common
Auscultation ± Murmur - -
Investigations
• Gastric aspirate
• Polymorph count
• Sepsis screen
• Chest X-ray
• Blood gas analysis
Pulse oximetry
• Effective non invasive monitoring of
oxygen therapy
• Ideally must for all sick neonates and
those requiring oxygen therapy
• Maintain SaO2 between 90 – 93 %
Shake test
• Take a test tube
• Mix 0.5 ml gastric aspirate +
0.5 ml absolute alcohol
• Shake for 15 seconds
• Allow to stand 15 minutes for
interpretation of result
RD in Newborn – Differential DiagnosisCondition Gestation History Clinical signs
RDS PT>FT APH/IDM asphyxia Retractions, grunt
Pneumoni
a
Any PROM, smelly
liquor, fever in
mother
Hypo/hyperthermia
leukocytosis or
neutropenia
MAS FT NSAF, asphysia
MA
Distended chest
Meconium staining
TTNB FT>PT C section Tachypnoea ++
PPHH Usually
FT
Asphyxia Profound cyanosis
CVS normal
X-Ray
Structures
– Ribs
– Vertebra
– Liver
– Stomach/ intestine
– Lungs
– Heart
– Trachea
– Esophagus
39
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
– cardiomegaly40
Roentgen Finding in RD in the Neonate
Pulmonary infiltrates Aeration e/o PAL
Distributio
n
Characteristis
Hyaline
membrane
disease
Diffuse Fine reticulogranula
pattern with air
bronchograms
Hypoaeration Present usually
as a complication
of respirator
therapy
Transient
tachypnoea
Diffuse Symmetrical stringy
perihilar infiltration
Hypoaeration Uncommon
Meconium
aspiration
syndrome
Usually
diffuse
Bilat patchy, course
infiltrate & atelectasis
alternating with areas
of alveolar
emphysema
Hypoaeration Often seen in the
absence of
respiratory
therapy
Neonatal
pneumonia
Variable but
usually
asymmetrica
l & localized
Variable pattern
ranges from localized
to diffuse alveolar or
interstitial disease
Mild
hyperaeration
Uncommon
X-ray - RDS
RDS
43
44
X-ray - MAS
MAS
46
MAS
47
TTN
48
X-ray- TTNB
X-ray – Congenital pneumonia
X-ray - Pneumothorax
Pneumonia/ Sepsis
53
Pneumothorax
54
Pneumothorax
Right lateral decubitus view of
pneumothorax
55
Pneumopericardium
56
Gomella, 2004
Respiratory distress - Management
• Monitoring
• Supportive
- IV fluid
- Maintain vital signs
- Oxygen therapy
- Respiratory support
• Specific
Oxygen therapy*
Indications
• All babies with distress
• Cyanosis
• Pulse oximetry SaO2 < 90%
Method
• Flow rate 2-5 L/ min
• Humidified oxygen by hood or nasal prongs
* Cautious administration in pre-term
Antenatal corticosteroid
- Simple therapy that saves neonatal lives
• Preterm labor 24-34 weeks of gestation
irrespective of PROM, hypertension and
diabetes
• Dose:
Inj Betamethasone 12mg IM every 24 hrs X
2 doses; or Inj Dexamethasone 6 mg IM
every 12 hrs X 4 doses
• Multiple doses not beneficial
Surfactant therapy - Issues
• Should be used only if facilities for
ventilation available
• Cost
• Prophylactic Vs rescue
Prophylactic therapy
Extremely preterm <28 wks
<1000 gm
Not routine in India
Rescue therapy
Any neonate diagnosed to have RDS
Surfactant therapy - Issues
Dose 100mg/kg phospholipid Intra tracheal
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
65
TTN presents:
Respiratory Assessment
–Tachypnea 60-150 bpm
–Nasal flaring
–Grunting
–Retracting
–Fine Rales
–Cyanotic
66
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
67
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!!
68
Congenital pneumonia
Predisposing factors
PROM >24 hours, foul smelling liquor,
Peripartal fever, unclean or multiple per
vaginal
Treatment
Thermoneutral environment, NPO, IV
fluids, Oxygen, antibiotics-
(Amp+Gentamicin)
Nosocomial pneumonia
Risk Factor : Ventilated neonates
: Preterm neonates
Prevention : Handwash
: Use of disposables
: Infection control measures
Antibiotics : Usually require higher antibiotics
Respiratory distress in a neonate with
asphyxia
• Myocardial dysfunction
• Cerebral edema
• Asphyxial lung injury
• Metabolic acidosis
• Persistent pulmonary hypertension
Pneumothorax
Etiology
Spontaneous, MAS, Positive pressure ventilation (PPV)
Clinical features
Sudden distress, indistinct heart sounds
Management
Needle aspiration, chest tube
Persistent pulmonary
hypertension (PPHN)
Causes
• Primary
• Secondary: MAS, asphyxia, sepsis
Management
• Severe respiratory distress needing ventilatory support, pulmonary vasodilators
• Poor prognosis
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?
74
Pneumothorax/ Air Leaks
Respiratory Assessment
– Tachypnea
– Nasal flaring
– Grunting
– Retractions
– BS absent or decreased
75
Pneumothorax/ Air Leak
Clinical Assessment
– Cyanotic
– Pale, gray
– Heart Rate
Tachycardia
Bradycardia
PEA
– Pulses
Normal
Poor
absent
76
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!!
77
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
78
CDH
79
CDH/ CCAM
Respiratory Assessment
– Tachypneic
– Retractions
– Nasal flaring
– Grunting
– Breath Sounds
Decreased on the affected side
May hear bowel sounds in chest with CDH
80
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
81
Left Congenital Diaphragmatic
Hernia
82
CCAM
83
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
84
Evaluation of RD in NB
History and physical examination
Dawnes’ or RDS score (clinical)
Arterial blood gases
Pulse oximetry – SaO2
Chest x-ray
Serum glucose and calcium; central hematocrit, WBC and differential; platelet count.
Maternal vaginal culture
Newborn surface (e.g. earcanal, gastric aspirate) smears, cultures (?), blood culture, urine culture (?). CSF culture (?)
Respiratory distress syndrome (RDS)
• Pre-term baby
• Early onset within 6 hours
• Supportive evidence: Negative shake test
• Radiological evidence
Pathogenesis of RDS
• Decreased or abnormal surfactant
• Alveolar collapse
• Impaired gas exchange
• Respiratory failure
RDS - Predisposing factors
• Prematurity
• Cesarean born
• Asphyxia
• Maternal diabetes
RDS - Protective factors
• PROM
• IUGR
• Steroids
Table 1. Potential Pulmonary Causes for Respiratory Distress in Neonates
Parenchymal conditions
Transient tachypnea of the newborn
Meconium aspiration syndrome and other aspirations
Respiratory distress syndrome
Pneumonia
Pulmonary edema
Pulmonary hemorrhage
Pulmonary lymphangiectasia
Developmental abnormalities
Lobar emphysema
Pulmonary sequestration
Cystic adenomatoid malformation
Congenital diaphragmatic hernia
Tracheoesophageal fistula
Pulmonary hypoplasia
Airway abnormalities Choanal atresia/stenosis
Laryngeal web
Laryngotracheomalacia or bronchomalacia
Subglottic stenosis
Mechanical abnormalities Rib cage anomalies (eg, Jeune syndrome)
Pneumothorax
Pneumomediastinum
Pleural effusion
Chylothorax
Respiratory distress
(needing referral)
• RDS (HMD)
• MAS
• Surgical or cardiac cause
• PPHN
• Severe or worsening distress
Meconium aspiration syndrome (MAS)
• Meconium staining
- Antepartum, intrapartum
• Thin
- Chemical pneumonitis
• Thick
- Atelectasis, airway blockage, air
leak syndrome
Meconium aspiration syndrome
• Post term/SFD
• Meconium staining – cord, nails, skin
• Onset within 4 to 6 hours
• Hyperinflated chest
MAS - Prevention
• Oropharyngeal suction before delivery of
shoulder for all neonates born through
MSAF
• Endotracheal suction for non vigorous*
neonates born through MSAF
*Avoid bag & mask ventilation till trachea is
cleared