Dr Varsha Atul ShahSenior Consultant

Dept of Neonatal and Devt Medicine, SGH

Visiting ConsultantDept of Child Devt,

KKH

Summary of presentationOverview- Background- Path physiology- Epidemiology- Mortality and MorbidityClinical PresentationDifferential diagnosisInvestigationsTreatment: Medical and surgicalFollow up care

Overviewappeared in the medical literature since its

first description in the early 18th century18th centuryIn 1946, Gross reported the first successful

repair of a neonatal diaphragmatic hernia In the 1960s, Areechon and Reid observed

that the high mortality rate of CDH was related to the degree of pulmonary hypoplasia at birth

Incidence1 in 2000-3000 live births 1 in 2000-3000 live births Accounts for 8% of all major congenital

anomaliesThe risk of recurrence of isolated (ie,

nonsyndromic) in future siblings is approximately 2% Familial is rare (< 2% of all cases)Both autosomal recessive and autosomal

dominant patterns of inheritance is reported

Genetic anomalies-SyndromeAssociated with genetic anomalies:Smith-Lemli-Opitz syndromeDiGeorge syndromeChromosome 15,18,13 and 21 anomaliesFryns syndromePallister-Killian syndrome

Pathophysiology and causeCause is unknownFailure of normal closure of the

pleuroperitoneal canal in the developing embryo

Abdominal contents herniate and compress the ipsilateral developing lung, causing pulmonary hypoplasia and hypertension

Path physiology of CDHIs associated with variable degree of pulmonary pulmonary

hypoplasia hypoplasia due to decrease in cross-sectional area of the pulmonary vasculature and alterations of the alterations of the surfactant systemsurfactant system

The lungs have a small alveolar capillary membrane small alveolar capillary membrane for gas exchange, which may be further decreased by surfactant dysfunction

There is increased muscularization increased muscularization of the intraacinar pulmonary arteries

In very severe cases, left ventricular hypoplasia is observed.

Pulmonary capillary blood flow is decreased Pulmonary capillary blood flow is decreased because of the small cross-sectional area of the pulmonary vascular bed, and flow may be further decreased by abnormal pulmonary vasoconstriction.

Types of congenital diaphragmatic hernia

Bochdalek hernia: Bochdalek hernia: Poster lateral (occurring at approximately 6 weeks' gestation)

Morgagni hernia: Morgagni hernia: Anteriomedial

The hiatus hernia

Left sided of CDHThe left-sided Bochdalek hernia occurs in

approximately 85% of cases85% of cases

Allow herniation of both the small and large bowel and intra-abdominal solid organs (stomach, liver) into the thoracic cavity

Right sided CDHOccurs in (13% of cases)Only the liver and a portion of the large

bowel tend to herniateBilateral hernias are uncommon and are

usually fatal.

Mortality/MorbidityMortality has traditionally been difficult to

determineThis is partially because of the "hidden mortalityhidden mortality"

for this condition who die in utero or shortly after birth, prior to transfer to a surgical site

A population-based study from Western Australia indicated that only 61% of infants with congenital diaphragmatic hernia are live born

Nearly 33% of pregnancies that involved a fetus were electively terminated

Mortality is reported to range from 40-62%40-62%

SexIt occurs equallyequally in both sexes

AgeIt is usually a disorder of the new-born new-born

period10% of patients may present after the new-

born period and even during adulthoodOutcome in patients with late presentation of

congenital diaphragmatic hernia is extremely good, with low or no mortality

Clinical PresentationHistoryIs diagnosed based on prenatal prenatal ultrasonography ultrasonography findings in approximately one half of affected infantsMay have a prenatal history of polyhydramniospolyhydramniosThe most commonly present with respiratory distress and cyanosis in the first minutes or hours of lifeThe respiratory distress can be severe and may be associated with circulatory insufficiency, requiring aggressive resuscitative measures.

Antenatal Diagnosis:59% antenatal detection with average age 24.2 24.2

weeksweeksPolyhydramniosIntrathoracic stomach or liverLung-to-head ratio and lung/transverse thorax

ratio.Usually at prenatal ultrasound (15 weeks).(15 weeks).Recently fetal MRI and fetal echocardiography,

helpful to determine degree of pulmonary hypoplasia. (MRI lung volumetry, left ventricular mass and pulmonary artery diameter)

Clinical PresentationHistoryHistoryRespiratory distress TachypneaCyanosis in the first minutes or hours of lifeThe respiratory distress can be severe and may be associated with circulatory insufficiency, requiring aggressive resuscitative measures.

Three general presentationsSevere respiratory distress Severe respiratory distress at the time of

birth.( Severe hypoplasia)Respiratory deterioration hours after delivery

(honeymoon period). Benefit from correction of hypoxemia and pulmonary hypertension.

Feeding difficulties, chronic respiratory disease, pneumonia, intestinal obstruction 24h after birth. (10-20% of patients).Best prognosis

Physical Examination Scaphoid abdomen, barrel-shaped chest, Scaphoid abdomen, barrel-shaped chest, and signs of

respiratory distress (retractions, cyanosis, grunting respirations)

In left-sided posterolateral hernia, auscultation of the lungs reveals poor air entry on the left, peristalsis heard in chest, with a shift of cardiac sounds over the right chest

In patients with severe defects, signs of pneumothorax (poor air entry, poor perfusion) may also be found

Associated anomalies occur in a relatively high percentage of infants

Dysmorphisms such as craniofacial, extremity abnormalities, or spinal dysraphism may suggest syndromic congenital diaphragmatic hernia

Differential DiagnosesCystic Adenomatoid MalformationBronchopulmonary sequestrationBronchogenic cystBronchial atresiaEnteric cystTeratomaDisorders of the Thoracic Cavity and PleuraPneumothoraxPrimary Pulmonary Hypertension of New-born

(PPHN)

Imagining study-Chest X-rayPlacement of an orogastric tube Placement of an orogastric tube prior to the

study helps decompress the stomach and helps determine whether the tube is positioned above or below the diaphragm

Typical findings in a left-sided posterolateral congenital diaphragmatic hernia include

- Air-filled or fluid-filled loops of the bowel in the left hemithorax

- Shift of the cardiac silhouette to the right- Look for evidence of pneumothoraxpneumothorax

Chest X-Ray

Imagining study-2D Echography2DE2DE: To exclude Cardiac anomalies (25%) and

degree of PPHN

Assessing myocardial function and determining whether the left ventricular mass is significantly decreased

Renal USGRenal USG: Genitourinary anomalies occur in 6-8% of infants

Cranial USG Cranial USG for CNS anomalies

Investigations-Lab studiesABG (pre-right radial and post ductal-left radial

or posterior tibial artery) measurements to assess for pH, PaCO2, and PaO2

Note the sampling site because persistent pulmonary hypertension of the newborn (PPHN) with right-to-left ductal shunting often complicates CDH

The PaO2 is often higher from a preductal (right-hand) sampling site

Serum lactate may be helpful in assessing for circulatory insufficiency or severe hypoxemia associated with tissue hypoxia

Medical Care in the delivery room: ( if the infant is known or suspected to have congenital diaphragmatic hernia)Immediately place a vented orogastric tube and connect it to continuous suction to prevent bowel distension and further lung compressionAvoid mask ventilation and immediately intubate the tracheaAvoid high peak inspiratory pressures and be alert to the possibility of early pneumothorax if the infant does not stabilize

InvestigationsSerum electrolytes, ionized calcium, and

glucose initially and frequentlyMaintaining glucose levels in the reference

range and maintaining calcium homeostasis are particularly important

Pre and Post Pulse OxymetryContinuous pulse oximetry is valuable in the

diagnosis and management of PPHNPlace oximeter probes at preductal (right-

hand) and postductal (either foot) sites to assess for a right-to-left shunt at the ductus arteriosus level

ProceduresUAC insertion: For frequent ABG monitoring and

BP monitoringUVC insertion for infusion of inotropes, Calcium

and for venous access Venoarterial or venovenous ECMO support is an

adaptation of cardiopulmonary bypass and involves a surgical team

NICU admission/Critically careMinimal Handling/stimulation, and gentle

suctioningMaintain temperatureContinuous monitoring of oxygenation,

transcutaneous PaO2, PaCO2, blood pressure, and perfusion

Maintain glucose (reflo regime) and ionized calcium

Inotropes for BPUse volume expansion and inotropic support with

dopamine, dobutamine, or milrinone , 2-20 mcg/kg/min

Dobutamine and milrinone may be particularly helpful if myocardial dysfunction is present

Epinephrine infusions may be necessary in severe cases; low-dose epinephrine (< 0.2 mcg/kg/min) may help to promote pulmonary blood flow and improve cardiac output

Maintain PaO2/PaCO2PaO2 concentrations greater than 50 mm Hg Permissive mild hypercarbia is allowedMaintain PH, avoid acidosisInhaled INO ( Nitric Oxide) as indicatedMagnesium sulphate loading and infusion if

no INO availableECMO if availableSedation is an important adjunctive therapy,

but the use of paralytic agents remains highly controversial

SedationFentanyl 1 mcg/kg/hour or Morphine infusionParalysis with Pancuronium, Vancuronium

(Controversial)

Surgical Care- AntenatalOpen fetal surgery: Open fetal surgery: remove the compression of

theabdominal viscera. High risk for fetus and themother. No survival advantage. (Harrison et al, J Ped

Surg, 1997)Fetal tracheal occlusion: Fetal tracheal occlusion: stimulation of lung

growthwith accumulation of fluid. Result in larger butpersistent abnormal lung. Steroids therapy weekly to improve lung function iscontroversial (risk of brain and body developmentproblems).

Surgical Care-Time of surgeryCirculatory stability, respiratory mechanics, and

gas exchange deteriorate after surgical repairThe ideal time to repair a congenital

diaphragmatic hernia is unknown Some suggest that repair 24 hours after 24 hours after

stabilization stabilization is ideal, but delays of up to 7-10 days are typically well tolerated, and many surgeons now adopt this approach

Some surgeons prefer to operate on these neonates when normal pulmonary artery pressure is maintained for at least 24-48 hours based on echocardiography.

Approaches for surgical repairAbdominal subcostalThoracotomyLaparoscopic vs ThoracoscopicMIS (Minimal Invasive surgery) ideal for Morgagni hernias but

can be challenging because the peumoperitoneum widens the defect.

Laparoscopy for Bochdalek’s has a high failure rate and is associated with ↑pCO2 and acidemia

Contraindicated if very high pCO2.Thoracoscopy is better approach for Bochdalek hernias with

recurrence of 14%. Open approach 3-22%.

Small defect can be repaired primarilyLarge defect will require abdominal or thoracic

muscle flaps, or prosthetic patch (tension free)

SurgeryBefore Surgery After Surgery

Follow up careGERDGrowth Failure (FTT)Foregut dysmotilityChronic lung diseaseScoliosisPectus excavatumNeurodevelopmental delay, Cognitive skills,

LD, seizures,Hearing loss

Further Inpatient Care-Respiratory careSeverely affected infants have chronic lung chronic lung

diseasediseaseMay require prolonged therapy with

supplemental oxygen and diuretics, an approach similar to that for bronchopulmonary dysplasia

The use of steroids, particularly high doses for prolonged periods, is controversial and may hinder appropriate lung and brain development

Late pulmonary hypertension Late pulmonary hypertension has been successfully treated with low-dose inhaled nitric oxide

Neurologic evaluationNeurologist or developmental pediatrician

perform an examination that includes an evaluation for CNS injury using head CT scanning or MRI

The incidence of hearing loss appears to be particularly high in patients with congenital diaphragmatic hernia (approximately 40% of 40% of infantsinfants)

An automated hearing test should be performed prior to discharge

Gastroesophageal reflux (GERD)GERD is very high in patients who survive

congenital diaphragmatic hernia, and studies document an incidence of 45-85%.45-85%.

Severe reflux may result in chronic aspiration and is, therefore, aggressively treated

Although most infants can be medically treated with H2-blockers or proton pump inhibitors in combination with a motility agent such as Domperidone, surgical intervention is sometimes required.

Further Outpatient Care- Failure To Thrive (FTT)Possible causes include increased caloric

requirements due to chronic lung disease, oral aversion after prolonged intubation, poor oral feeding due to neurologic delays, and gastroesophageal reflux.

More than 50% of patients are below the 50% of patients are below the 25th percentile25th percentile for height and weight during the first year of life

In one study, one third of infants required gastrostomy tube placement to improve caloric intake

Developmental AssessmentBecause of the risk for CNS insult and

sensorineural hearing loss, infants should be closely monitored for the first 3 years of life, preferably in a specialty follow-up clinic

These risks are particularly high in infants who are discharged home on supplemental oxygen

Reassess hearing at age 6 months (and later if indicated) because late sensorineural hearing loss occurs in approximately 40% of 40% of patientspatients

School ageEven if a child has no major

neurodevelopmental delays, he or she should be evaluated prior to entering school to determine if any subtle deficits may predispose the child to learning disabilities.

Nursing related pointersDelivery room-Do not bag and Mask, early intubationInsert nasogastric tube to decompress stomach and

gutSat O2 monitor on right palm and left palm(pre and

post)Thermoregulation maintain temp 36.7-37.3°C by

control of ambient and/or skin temperatureMinimal stimulation/HandlingMinimal stimulation/Handling, XR,suction and

noiseStrict input outputUAC/UVC or IA line monitoring, perfusion chartInotrope infusion, Y site compatibility

Nursing related pointersHFOV, ETT position, mechanical ventilation charting, prevent

nosocomial pneumonia and infection controlEducate use and connection for INO NOXBOXAvoid hypoxia, hypercarbia, acidosisSedation, pain management Inline suctioning, Chest PTDevelopmental care- avoid noise, bright light etcFeeding, Expressing breast milk, Weight chart, wound care Positioning and posture: - Supportive positioning (Position infant with affected side Position infant with affected side

down to aid ventilation of the “good” lung)down to aid ventilation of the “good” lung)- Also position infant in a nesting position to decrease agitationParent Education and support

Parent educationParents receiving the diagnosis of Congenital

Diaphragmatic Hernia initially experience emotional distress, which has been shown to impair optimum learning

Studies of prospective parents of an infant with a fetal anomaly revealed their inability to assimilate all the information given to them in one session

Parents have indicated that both visual and auditory learning is important and have suggested that written material and drawings would be useful in helping parents retain and review information.

Parent educationDescription of Congenital Diaphragmatic Hernia Explanation of what to expect in the delivery room Tour of neonatal unit Explanation of what to expect upon admission to

NICU and first day of life including intubation, ventilation, antibiotics, umbilical venous/arterial lines, IV therapy, gastric decompression and cardiac monitoring.

Education upon admission to NICU: Reinforce information given prenatally as noted

above Discuss plan of care given to the parents prenatally:

Parent EducationPre-Op: Update parents to plans for surgery and what to expect post-operativelyPost-operative Education: Update parents about infant’s status post-operatively and review any new equipment, medication, or therapies that have been added to infant’s care.Discharge Education: General Infant Care Car seat Safety Care for the infant with reflux (as appropriate) Care for the infant on oxygen therapy (as appropriate)

ConclusionCDH is a congenital anomaly with a high mortalityUsually associated with pulmonary hypoplasia and hypertensionSurgical repair is only treatmentDelayed surgery until the patient is stable is associated with

better outcomesCongenital cardiac and renal diseases, hypoxemia and

hypercapnia increases mortalityHFOV, ECMO, iNO has improved the survival of CDHPermissive hypercapnia with acceptable pO2 has shown to

improve survivalLong term follow up is necessary to detect complicationsTracheal occlusion in utero, keeps lung expanded but is a

abnormal lungPrimary repair if small defect, patch if large defect, to prevent

tension