Neonatal respiratory distress

Congenital diaphragmatic hernia, Pneumothorax, MEconium aspiration, Transient tachypnoea of the newborn

Content

• What is respiratory Distress? • Pathophysiology of respiratory distress • Can it be non specific? • How do we diagnose underlying reason? • Differential diagnosis • Investigations • Important points in the History • Respiratory causes • X ray features of different conditions • Cardiac causes

What is respiratory Distress?

• A baby with difficulty in breathing – ‘Respiratory distress’

• How do you identify? (signs of respiratory distress) ➢ Tachypnea (RR over 60) ➢ Increased work of breathing - Recessions – Intercostal, Subcostal, Sternal - Nasal flaring ➢Expiratory grunting (expiration agaisnt a forced glottis) ➢Low oxygen saturation

• As the condition deteriorates cyanosis may develop

Pathophysiology of respiratory distress

• Stiff Lungs due to surfactant deficiency – difficult to inflate (IRDS) • Lungs filled with fluid (pulmonary edema) or irritant material (meconium, milk) • Problems with thoracic cavity – fluid or air filling plural cavity (pneumothorax, effusion) • Neuro-muscular problems (myopathy) • Problems of Respiratory center (Drugs, Perinatal Hypoxia) Pethidine and diazepam... Can depress respiratory center in

Can it be non specific?

• Newborns have very few ways of manifesting illness • Manifestations can be not specific for a system • Poor feeding • Change in colour • Lethargy • Difficulty in breathing

How do we diagnose underlying reason?

• So respiratory distress in a newborn is non-specific • Aetiology may vary • May be due to different pathologies • To decide on the most likely diagnosis/diagnoses • History • examination • investigations

Differential diagnosis

• Congenital - lung - absent / poorly developed lung (pulmonary aplasia/hypoplasia) - cystic lung disease - heart disease • Obstruction –of airway (choanal atresia, large tongue) • Infection – pneumonia, sepsis • Inflammation – meconium aspiration syndrome • Metabolic – acidosis, drugs • Traumatic – hemorrhage, asphyxia

Investigations

Gbs colonisation of genital tract?

• Differential diagnosis will depend on the history and Examination • First line Investigations - Chest X-ray, FBC, CRP, Blood culture • Other investigations will depend on likely differential diagnoses • Depending on the circumstances ECG, 2DE etc. • Certain other investigations are necessary in management rather than diagnosis - RBS because it can cause feeding problems, Blood gas, SE, BU, SC etc

Important points in the History

• Maturity of the baby and BW • Antenatally detected abnormalities • History of meconium in liquor • History of asphyxia/hypoxic insult • Time of onset of symptoms • Progression of symptoms • Signs outside the respiratory system

Mother had infection or fever around perinatal area

Transient tachypnea of new born But if more than 4 hours then need to diagnose But always start on anitbiotics

Respiratory causes

• IRDS • Meconium aspiration • Pneumothorax • Pleural effusion • Congenital pneumonia • Lung aplasia/hypoplasia • Cystic adenamatoid malformation (CAM) • Congenital empysema

Babies start breathing after birth.. First cry.. Before that filled with liquor. Liquor on mouth and GI tract and lung is collapse.

Hypoxic during delivery or before delivery they can gasp and then inhale meconium and start the lung expand with meconium.

Resourtaory distress in hypoxia? Lactic acidosis, metabolic acidosis and they increase respiratory rate..

Radiological findibgs and gradings of IRDS?

Air bronchi gram... Grondglass appearance

Cotton wool appearance in meconium aspiration Nodular opacitues

Common side of diaohraognaic hernia?

Resourtaory distress... And heart sounds pushed over? Diaphragmatic hernia...other causes? Management will learn in neonatal surgical conditions

Black fields x rays? Black is emphysema

Pneomothorax x ray findings important....(need to know thoroughly)

Cardiac causes

• Conditions causing left heart obstruction are the conditions which lead to symptoms in the immediate newborn period • Eg. Obstructed Total Anomalous Pulmonary Venous drainage Cardiac Abnormalities the could manifest as rs distress???

Idiopathic Respiratory Distress Syndrome

• Specific entity • Prematurity is the greatest risk factor - less than 28 weeks – 80% - 32-36 weeks – 15% - more than 37 weeks – 5% • Caused by a deficiency of surfactant – surfactant deficient lung disease • Pathology – hyaline membrane disease • Usually a condition common in the preterm • Characteristic clinical course

IRDS

Risk increased in ➢Maternal DM ➢Multiple births ➢Asphyxia ➢Hypothermia (cold) ➢Male sex

Risk decreased in ➢ PIH or chronic hypertension ➢ antenatal steroids ➢ maternal heroin addiction ➢ PROM

IRDS - Pathology

• Lack or deficiency of surfactant • High surface tension in the alveoli and small airways • High inflation pressure needed to expand at inspiration • Tendency to collapse at the end of expiration • Failure to establish a good FRC • Atelectasis – V/Q mismatch → hypoxia • Increased dead space

IRDS - Pathophysiology

• Increased work of breathing hypercapnia and acidosis • Insufficient ventilation • Combination of hypoxia, hypercapnia and acidosis leads to pulmonary vasoconstriction and R to L shunting via FO and DA • Decreased pulmonary blood flow ischemic damage to lung • Exudation of protein containing fluid hyaline membrane

Clinical course

• Develops within minutes of birth ( up to 4 hours) • Severity increased gradually up to 48 – 72 hours • Remains stable for a variable length of time – few days to a week • Improvement – reduced requirement of ventilator support and oxygen

IRDS

• Self limiting course • Aims of management is to improve oxygenation and aid in CO2 elimination • Maintain the rest of baby’s physiology at optimum – Temp, BS, SE etc • Wait for recovery • DO NOT CAUSE MORE DAMAGE

Prognosis

• Neurologically intact survival increased with • Early provision of intensive care/early use of CPAP • Antenatal steroids • Post natal surfactant • Improved modes of ventilation to minimize lung damage • Developmentally appropriate care

Study (Home work)

• Other main causes of respiratory distress and diagnosis and management • How to suspect each diagnosis with history and examination • Investigations to confirm/support diagnosis of each condition • Common causes of RDS in a term baby and a preterm baby

Cardiac causes of resou systems... Even win management still the oxygen saturation us low.. Then can be cardiac cause and need echo cardiography....

That slide and algorithm for when to investigate pulse oxymetry

Need to give dexmethosaone steroid atleast 24 hours before delivery!!!!!!!.

Basic management of diaphragmatic hernia.. Can't be managed by ambu ventilation as can make it worse by dilating bowels. So ned to drain the bowels and collapse it by nasi gastric tube.... Can only help by endotracheal tube. Its the only condition where ambu ventilation is bad. Can cause pul hypertension so need to do othe rtreatkents for that.

Newborn care guidelines

Guidelines for surfactant use

Add from the guidelines below

Surfactant-Therapy.pdf

496.9KB

Respiratory-Distress-in-the-Newborn.pdf

495.1KB