Grand seminar aprl 9 th

APPROACH TO A CASE OF RESPIRATORY DISTRESS IN THE

NEWBORN

DR JAGAN MOHAN VARAKALA

• Causes of significant morbidity and

mortality newborn

• Incidence 4 to 6% of live births

• Many are preventable

• Early recognition, timely referral,

appropriate treatment essential

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OBJECTIVES

• TO IDENTIFY THE RESPIRATORY PROBLEMS IN THE NEWBORN

• TO UNDERSTAND THE ETIOLOGY OF RESPIRATORY PROBLEMS IN THE NEWBORN

• TO LEARN ABOUT THE MOST COMMON RESPIRATORY PROBLEMS IN THE NEWBORN

APPROACH TO A CASE OF RDS

• WHY DO NEWBORNS DEVELOP HIGHER INCIDENCE OF RESPIRATORY DISTRESS ?

APPROACH TO A CASE OF RDS

• MAINLY BECAUSE OF DIFFICULTIES IN ADAPTING TO TRANSITION

• ASSSOCIATED DEVELOPMENTAL AND PATHOLOGIC PROBLEMS

• DUE TO PREMATURE BIRTHS

FETUS TRANSITION NEWBORN

TRANSITIONAL CIRCULATION

UVDV IVC RA

FO LA LV

SVC RA RV

DA Des Ao

F

E

T

A

L

Fetus Birth Newborn

Pu

lmo

na

ry V

as

cu

lar

Re

sis

tan

ce

PaO2

pH

PaCO2

Leukotrienes

Endothelin

PaO2

pH

PaCO2

Nitric oxide

Prostacyclin

CHANGES IN PULMONARY VASCULAR RESISTENCEAT BIRTH

FIRST BREATH

NEONATE

WITH

RESPIRATORY

DISTRESS

LABORATORY

TESTS

DIFFERENTIAL

DIAGNOSIS

CARDIACPULMONARY MOTHER CAUSES

HISTORYPRENATALINTRAPARTUM

PHYSICAL EXAMNATION

FINAL DIAGNOSIS

MANGEMENT:GENERAL AND SPECIFIC

APPROACH TO A CASE OF RDS

Determining Differential Diagnosis

What you need to know…History•

•

•

Presentation/X-raysLab values

clinical assessment

•

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EVALUATION OF NEONATES WITH RESPIRATORY DISTRESS

Ante History-obsterician friend

Premature delivery

Postmature delivery

Fetal distress

Meconium-stained

fluidMaternal diabetes

Oligohydramnios/

polyhydramnios

Decreased fetal movements

Traumatic delivery

Drugs

Cesarean section

Vaginal bleeding

Antenatal Steroids

• Respiratory distress syndrome (RDS)

• Meconium aspiration syndrome (MAS)

• Transient tachypnoea of newborn (TTNB)

• Asphyxial lung disease

• Pneumonia- Congenital, aspiration, nosocomial

• Persistent pulmonary hypertension (PPHN)

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• Tracheo-esophageal fistula

• Diaphragmatic hernia

• Pierre -Robin syndrome

• Choanal atresia

• Congenital lobar emphysema

10

Early progressive - Respiratory distresssyndrome or hyalinemembrane disease (HMD)

Early transient - Asphyxia, metaboliccauses, hypothermia

PneumoniaAnytime -

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TTNB, polycythemia

MAS, asphyxia,

malformations

Cardiac

Early well looking

Early severe distress

-

-

Late sick with

hepatomegaly

-

Late sick

Anytime

with shock - Acidosis

Pneumonia-

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• Obvious malformation

• Scaphoid abdomen

• Frothing

• History of aspiration

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EVALUATION OF NEONATES WITH RESPIRATORY DISTRESS

Major signs:

cyanosis, tachypnea

grunting, retraction, flaring

Stridor, wheezes,

hoarseness, and other

airway findings

CardiovascularassessmentBlood pressure

Neurologic assessment

Temperature

Physical Exam

Downes score*0 1 2

Resp. rate

Central

cyanosis

Retractions

Grunting

Air entry

<60

None

60-80

None with

40% FiO2

Mild

Minimal

Decreased

>80

Needs

>40% FiO2

Severe

Obvious

Very poor

1.

2.

None

None

Good

3.

4.

5.

* Score > 6 indicates severe distress

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• Downes J,Vidyasagar D and Boggs T (1971)

Color—pink, dusky, Central Cyanosis Peripherally

Heart rate

Pulses Distal vs Central

Perfusion Capillary RefillTime Blood Pressure

,pale,mottled

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EVALUATION OF NEONATES WITH RESPIRATORY DISTRESS

Laboratory Workup

Chest radiograph

Arterial blood gas

Blood glucose

Central hematocrit

White blood cell

and differential

If indicated:

Blood culture

Echocardiogram

Other diagnostic

imaging

TTNTERM INFANT IN RESPIRATORY DISTRESS

A male infant weighing 3000g is born at 36 weeks'gestation, with normal Apgar scores.Examinationthe child is tachypneic, with subcostal retractions.Lung sounds are clear and there is no heartmurmur.

X-Ray findings Prominent Perihilar

Hyperinflation

Fluid in fissure

streaking

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X-ray

Fluid in the fissure

What Next ?

Most common diagnosis of respiratorydistress in the newbornIneffective clearance of amniotic fluid

from lungs with deliveryMost often seen at birth or shortly after birth

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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)

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70

• Myocardial dysfunction

• Cerebral edema

• Asphyxial lung injury

• Metabolic

• Persistent

acidosis

pulmonary hypertension

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CASE HISTORY

• A 3kg female infant is delivered via caesarean section at 41 weeks’ gestational age because of MSAF. She is limp and cyanotic at birth with minimal respiratory effort. Apgar scores are 2 and 7 at 1 and 5 minutes, respectively. Temp:is 99°F (37.2°C), HR: 177/ minute, and RR: 80/minute.

• Physical examination findings include marked increased work of breathing with nasal flaring, subcostal and suprasternal retractions.

• Barrel-shaped chest, and coarse rhonchi in bilateral lung fields.

• Chest X Ray findings…

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Increased AP diameter

Hyperinflation

Atelectasis

Note meconium staining of skin Increase AP

diameter of chest and the convexity of the sternum

MAS:PATHOPHYSIOLOGY

Vidysagar D. PEDIATRICS 1975

PREVENTION OF MECONIUM ASPIRATION SYNDROME(MAS)

• Because of potential morbidity and

mortality from MAS,

prevention would clearly be beneficial.

• This has led to a number of antenatal,

intrapartum and postnatal preventative

therapies with a varying degree of

success.

IS MENONIUM PRESENTYESNO

IS THE BABY VIGOROUS?

Intubate and tracheal suction.

CONTINUE WITH RESUSCITATION

CLEAR MOUTH AND NOSE FROM SECRETIONS

DRY,STIMULATE AND REPOSITION

GIVE OXYGEN AS NECESSARY

NOYES

Bag and masking is contraindicated

Small right pneumothorax

Pneumomediastinum

Pneumopericardium

EtiologySpontaneous, MAS, Positive pressureventilation (PPV)

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Respiratory Assessment Tachypnea

Nasal flaring

Grunting

Retractions

BS absent or decreased

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Clinical Assessment Cyanotic

Pale, gray

Heart Rate

▪

▪

▪

Tachycardia

Bradycardia

PEA

Pulses

▪

▪

▪

Normal

Poor

absent

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Perfusion Capillary Refill (CRT)

Blood Pressure if monitoring Arterial narrowing pulse pressure

Deformities of ChestWall

Asymmetry of chest

Line,

CHEST X-Ray speaksfor itself!!

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Pneumothorax/Airleaks

•Management• Needle aspiration, chest tube

TERM INFANT IN RESPIRATORY DISTRESS

Left diaphragmatic hernia

Defect present at birth Increased risks: Parents have CHD? Siblings have CHD? Maternal diabetes

often picked up on usg

Exposure to German mother HIV+

measles, toxoplasmosis, or if

Alcohol use during pregnancy Cocaine use during pregnancy

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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

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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

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Hyperoxia Test

• Obtain ABG–> Then place the patient on 100% O2 for 10 minutes then repeat ABG , If the cyanosis is pulmonary , the PaO2 should be increased by 30 mm of Hg. If the cause is cardiac , there will be minimal improvement in PaO2.

Echocardiogram Best test to aid in diagnosis

Cardiac Cath for possible intervention

PRETEM INFANT WITH RESPIRATORY DISTRESS

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Respiratory Distress Syndrome

• Also called as hyaline membrane disease• Most common cause of respiratory distress in

premature infants, correlating with structural & functional lung immaturity.

• 1/3 infants born between 28 to 34 weeks, but less than 5% of those born after 34 weeks.

INCREASED RISK FACTORS

• Infants of diabetic mothers

• Delivery before 37 wk gestation

• Multifetal pregnancies

• Cesarean section delivery

• Precipitous delivery

• Asphyxia

• Cold stress

• History of previously affected infants

DECREASED RISK FACTORS

• Chronic or pregnancy-associated hypertension

• Maternal opiate addiction

• Prolonged rupture of membranes

• Antenatal corticosteroid use

PATHOPHYSIOLOGY

PATHOPHYSIOLOGY

• Surfactant deficiency - decreased production and secretion

• Present in amn.fluid:28-30wks, mature levels after 35 wks

• Surfactant reduce surface tension and prevent the collapse alveoli

• Alveolar atelectasis, hyaline membrane formation, and interstitial edema make the lungs less compliant, so greater pressure is required to expand the small alveoli and airways

PATHOPHYSIOLOGY (CONTD…)

• Decreased lung compliance- insufficient alveolar ventilation – result in hypercapnia

• Combination of hypercapnia, hypoxia, and acidosis → pulmonary arterial vasoconstriction → increased R → L shunting through the foramen ovale and ductus arteriosus →Pulmonary blood flow is reduced → ischemic injury cap endothelium & alveolar epithelium → leak of plasma (proteinaceous material) into the alveolar spaces

PATHOPHYSIOLOGY (CONTD…)

• leak of plasma (proteinaceousmaterial) into the alveolar spaces →combine with fibrin & necrotic alveolar pneumocytes & form hyaline membrane

• Hyaline membranes: coagulum of sloughed cells and exudate, plastered against epithelial basement membrane

Primary Hyaline membranedisease(HMD):e.g Prematurity

Secondary HMD e.g Meconium aspirationsyndrome, asphyxial lung injury, pulmonaryhaemorrage

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PREVENTION

• Prevention of prematurity

• Lecithin:sphingomyelin ratio in amniotic fluid: >2 means mature lungs <1.5 means HMD

• Betamethasone to women 48hr before the delivery - between 24 and 34 wk of gestation- 6mg IM for 4 doses 12 hrs apart or 12 mg IM for 2 doses 12 hrs apart

PREVENTION (CONTD…)

• First dose of surfactant into the trachea of symptomatic premature baby immediately after birth (prophylactic) or during the first few hours of life (early rescue)

• MonitoringSupportive

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• Avoid hypothermia

• IV Calories and fluids

• Warm humidified oxygen

• CPAP : prevents collapse of surfactant-deficient alveoli

• Assisted ventilation

• High-frequency ventilation (HFV )

Indications

• All babies with distress

• Cyanosis

• Pulse oximetry SaO2 < 90%

Method

• Flow rate 2-5 L/ min

• Humidified oxygen by hood ,nasal prongs ,or CPAP

* Cautious administration in pre-term

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DEFINITIVE TREATEMENT

SURFACTANT THERAPY : DEFINITIVE

TREATEMENT

• Multidose endotracheal instillation : 4ml/kg

• Treatment (rescue) is initiated as soon as possible in the 1st 24hr of life

• Dose repeated - via the ET tube 6–12hrly for a total of 2-4 doses

• Appropriate monitoring equipment must also be available - radiology, blood gas laboratory, and pulse oximetry

INDICATIONS FOR MECHANICAL VENTILATION

• Clinical: Absolute: Apnea (intractable), gasping, cyanosis not responsive to O2

RDS SCORE: >4-6 ,Increased Fio2,Work of breathing

• Laboratory (while on CPAP or FiO2 > 0.5):

pH < 7.25 with increasing PCO2 > 50 mm Hg

(or) PO2 < 60 and / or SpO2 < 85 %

• Other: Surgical procedures, compromised airway

Neonate with

respiratory

distress Abnormal

Chest X-Ray

?

Common Uncommon

Yes Look for

abnormalities

of:

No

Resp Distress Synd

Transient Tachypnea

Aspiration Syndromes

Pneumonia

Air leaks

Effusion

Pulmonary Edema

Diaphrag. Hernia

Trach-Esoph fistula

Cysts, tumors

Hypoplasia

Hemorrhage

Cong. Lobar Emph.

Lymphangiectasia

Sequestration

AV fistulae

Perfusion,

BP, HCT

Upper or lower

airway

Cardiac problems

Neuro-

muscular

Diaphragm or

Chest wall

AbdomenOther or

Mixed findings

IN SUMMARY

TAKE HOME MESSAGES

• Obtain good Prenatal and Perinatal history• Identify at risk pregnancies• Establish communication between

OB/PED/NEONATAL services prior to delivery• Early diagnosis of infant in Respiratory Distress,

using:• Clinical and Diagnostic work up :RDS score, pulse

oximetry, X-ray ,CBC.

• EARLY AND SAFE TRANSFER TO LEVEL II AND III NICU WILL SAVE MANY BABIES

Thank You …

Thank You …