respiratory distress in newborn

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


• 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


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


Is the disorder new / chronic / recurrent?

Chronic disorder – BPD

Recurrent disorders

- Aspiration pneumonia

- Pulmonary hemorrhage

- Lobar atelectasis


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

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


– 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


– 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


(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

respiratory distress in newborn

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