2. Diaphragmatic HerniaDiaphragmatic Hernia
๏ Migration of abdominal viscera through aMigration of abdominal viscera through a
defect in the diaphragm into the chestdefect in the diaphragm into the chest
๏ Three anatomical formsThree anatomical forms
Posterolateral foramen of BochdalekPosterolateral foramen of Bochdalek
Substernal foramen of MorgnaniSubsternal foramen of Morgnani
Oesophageal hiatusOesophageal hiatus
๏ The termThe term Congenital diaphragmatic herniaCongenital diaphragmatic hernia
refers to the first.refers to the first.
3.
4. EmbryologyEmbryology
๏ Four sources for the diaphragmFour sources for the diaphragm
i)i) Septum transversumSeptum transversum
ii) Dorsal mesogastriumii) Dorsal mesogastrium
iii) Dorsal body wall musculatureiii) Dorsal body wall musculature,,
Anterior costal sructures.Anterior costal sructures.
iv) Pleuroperitoneal membranesiv) Pleuroperitoneal membranes
5. Non closure of PPC leads to a
posterolateral defect by 8th
week
โ
Bowel that is returning into abdominal
cavity enters thoracic cavity
โ
Direct compression of the developing
lung and pulmonary hypoplasia.
6. Lung DevelopmentLung Development
๏ Develops as ventral groove in floor of pharynxDevelops as ventral groove in floor of pharynx
๏ By 6By 6thth
wk two lung buds formedwk two lung buds formed
๏ All generations of bronchi btwn 6 โ 16 wksAll generations of bronchi btwn 6 โ 16 wks
๏ Air sacs & alveoli develop & mature betweenAir sacs & alveoli develop & mature between
16 wks โ 8 yrs.16 wks โ 8 yrs.
๏ Pulm vasculature mimics bronchialPulm vasculature mimics bronchial
development.development.
7. Lung development in CDHLung development in CDH
๏ Ingrowth of abdominal contents results inIngrowth of abdominal contents results in
pulmonary hypoplasia โ there is reduced lungpulmonary hypoplasia โ there is reduced lung
volume & weight & alveolar surface area which isvolume & weight & alveolar surface area which is
permanent.permanent.
๏ Deficiency of type II pneumocytes results inDeficiency of type II pneumocytes results in
decreased surfactant.decreased surfactant.
๏ Decrease in overall cross sectional area ofDecrease in overall cross sectional area of
pulmonary vascular bed.pulmonary vascular bed.
๏ Muscular hyperplasia in the media of pulmonaryMuscular hyperplasia in the media of pulmonary
arteries from central arteries till the preacnararteries from central arteries till the preacnar
arteries.arteries.
8. Fetal pulmonary circulationFetal pulmonary circulation
๏ Pulm blood flow - 7% of fetal cardiac output.Pulm blood flow - 7% of fetal cardiac output.
๏ Pulm vasc resistance remains high in the fetus.Pulm vasc resistance remains high in the fetus.
๏ Shunts oxygenated blood from placenta throughShunts oxygenated blood from placenta through
foramen ovale & ductus arteriosus in a RโLforamen ovale & ductus arteriosus in a RโL
shunt into systemic circulationshunt into systemic circulation
9. Transitional pulmonary circulationTransitional pulmonary circulation
๏ Sudden decrease in pulm vascSudden decrease in pulm vasc
resistance.resistance.
๏ Concomitant increase in systemic vascConcomitant increase in systemic vasc
resistanceresistance..
๏ 10 fold increase in pulm vasc flow.10 fold increase in pulm vasc flow.
๏ Increased left atrial pressure.Increased left atrial pressure.
๏ Closure of foramen ovale.Closure of foramen ovale.
๏ Blood flow in the ductus arteriosusBlood flow in the ductus arteriosus
reversed.reversed.
๏ The duct closes in response to highThe duct closes in response to high
oxygen tension.oxygen tension.
10. Reasons for fall in pulm tension areReasons for fall in pulm tension are
๏ Lung expansion & onset of ventilationLung expansion & onset of ventilation
๏ Decrease in CO2 concentrationDecrease in CO2 concentration
๏ Increase in alveolar O2 tension.Increase in alveolar O2 tension.
๏ The actual pulm vasodilation is mediatedThe actual pulm vasodilation is mediated
through Nitric Oxidethrough Nitric Oxide
11. Persistent Pulmonary HypertensionPersistent Pulmonary Hypertension
(PPHN )(PPHN )
๏ Persistence of RโL shunt @ atrial & duct levels withPersistence of RโL shunt @ atrial & duct levels with
delivery of unsaturated blood into systemicdelivery of unsaturated blood into systemic
circulation.circulation.
๏ As blood flow in the shunt increases systemic O2As blood flow in the shunt increases systemic O2
saturation falls. Mixed venous return to the right sidesaturation falls. Mixed venous return to the right side
of the heart becomes progressively desaturated.of the heart becomes progressively desaturated.
๏ The resulting hypoxia further increases pulmThe resulting hypoxia further increases pulm
resistanceresistance
12. PFC in CDHPFC in CDH
๏ Hyperplasia of arterial mediaHyperplasia of arterial media
๏ Increased levels of vasoactive peptides like endothelin 1,Increased levels of vasoactive peptides like endothelin 1,
TXA2TXA2
๏ Increased sensitivity & reactivity of pulm vasc to theseIncreased sensitivity & reactivity of pulm vasc to these
peptides - response more severe & prolonged.peptides - response more severe & prolonged.
๏ Hypoxia, acidosis, hypercarbia, hypothermia, stress,Hypoxia, acidosis, hypercarbia, hypothermia, stress,
sepsis etc.sepsis etc.
๏ However over a period of days the medial hyperplasiaHowever over a period of days the medial hyperplasia
and hyper reactivity is reducedand hyper reactivity is reduced
13. Pathophysiology of CDHPathophysiology of CDH
๏ Pulm hypoplasiaPulm hypoplasia
๏ Labile & reactive pulm vasc resulting in PFCLabile & reactive pulm vasc resulting in PFC
๏ Surfactant deficiencySurfactant deficiency
๏ Cardiac dysfunction with lowered cardiacCardiac dysfunction with lowered cardiac
output complicates these problems.output complicates these problems.
14. IncidenceIncidence
๏ 0.3 / 1000 live births0.3 / 1000 live births
๏ More than 85% occur on the left sideMore than 85% occur on the left side
๏ Associated anomalies:Associated anomalies:
Seen in about 20% casesSeen in about 20% cases
MalrotationMalrotation
Neural tube defectsNeural tube defects
Cardiac anomaliesCardiac anomalies
Cleft palate, Omphalocoele etc.Cleft palate, Omphalocoele etc.
15. Clinical featuresClinical features
๏ Respiratory distress, cyanosis, gasping.Respiratory distress, cyanosis, gasping.
๏ Scaphoid abdomen & asymmetric funnelScaphoid abdomen & asymmetric funnel
chestchest
๏ Tracheal shift to opposite sideTracheal shift to opposite side
๏ Absence of breath soundsAbsence of breath sounds
๏ Bowel sounds in chestBowel sounds in chest
16. DiagnosisDiagnosis
๏ Often made on prenatal USG โ GastricOften made on prenatal USG โ Gastric
bubble / intestinal loops in the chest,bubble / intestinal loops in the chest,
PolyhydramniosPolyhydramnios
๏ Post natal Chest X rayPost natal Chest X ray
19. Poor prognostic factorsPoor prognostic factors
๏ Detected before 24 wksDetected before 24 wks
๏ PolyhydramniosPolyhydramnios
๏ Presence of stomach within the chestPresence of stomach within the chest
๏ Right sided herniaRight sided hernia
20. ManagementManagement
๏ Prenatal carePrenatal care
๏ Support fetus & mother, bringing them toSupport fetus & mother, bringing them to
delivery as close to term as possible.delivery as close to term as possible.
๏ Refer to tertiary centre.Refer to tertiary centre.
๏ Spontaneous delivery preferred.Spontaneous delivery preferred.
21. Preoperative carePreoperative care
๏ CDH is aCDH is a physiologic emergencyphysiologic emergency & not a& not a
surgical emergencysurgical emergency
๏ Do not bag/mask the baby.Do not bag/mask the baby.
๏ Insert NG tube, aspirateInsert NG tube, aspirate
๏ O2 by prongs / mask / endotracheal tubeO2 by prongs / mask / endotracheal tube
22. Stabilise the cardiorespiratoryStabilise the cardiorespiratory
systemsystem
๏ VentilationVentilation
๏ Pharmacology to reduce pulm pressure โPharmacology to reduce pulm pressure โ
TolazolineTolazoline
NitroprussideNitroprusside
NitroglycerineNitroglycerine
๏ Nitric oxideNitric oxide
๏ SurfactantSurfactant
23. SurgerySurgery
๏ Subcostal incision. Viscera gently reducedSubcostal incision. Viscera gently reduced
๏ Defect examined. Usually there is good anteriorDefect examined. Usually there is good anterior
lip and poorly formed posterior lip covered withlip and poorly formed posterior lip covered with
peritoneum.peritoneum.
๏ Primary repair with non-absorbable suturePrimary repair with non-absorbable suture
๏ If defect is too large prosthetic patch has to beIf defect is too large prosthetic patch has to be
used.used.