Congenital diaphragmatic hernia

1. Congenital diaphragmatic hernia Dr. S. Parthasarathy MD., DA., DNB, MD (Acu), Dip. Diab.DCA, Dip. Software statistics PhD (physio) Mahatma gandhi medical college and research institute, puducherry, India Dr.S.Parthasarathy MD DNB PhD

2. What is it ?? • Herniation of abdominal contents in the thoracic cavity through a cong defect in the diaphragm Dr.S.Parthasarathy MD DNB PhD

3. How common ?? • Incidence:- • 1 in 2000 to 1 in 4000 • M:F : 2:1 • Lt : Rt : 5:1 Dr.S.Parthasarathy MD DNB PhD

4. Sites 80 % 10 % Dr.S.Parthasarathy MD DNB PhD

5. Then what is eventration ?? • Eventration of diaphragm- • absence of muscular component of the diaphragm, may be asymptomatic to s/s similar to Bochdalek hernia • Reported percentages vary Dr.S.Parthasarathy MD DNB PhD

6. Aetiology • Unclear • 2 % familial • Genetic association - trisomies13, 18 and 21. • Chromosome region 15q26 – necessary for diaphragm development Dr.S.Parthasarathy MD DNB PhD

7. 40 % associated with other anomalies • Cardiac anomalies • DuctusarteriosusSeptal defects, AV valve defects, Aortic arch hypoplasia • Musculoskeletal • Hypodactyly Long bone aplasia ,Talipes • CNS • Microcephaly, Cerebral palsy • Genitourinary • Hypospadias Renal dysplasia Dr.S.Parthasarathy MD DNB PhD

8. Embryology • The diaphragm, lungs, and gastrointestinal tract develop synchronously. • Developing Diaphragm envelops the esophagus, inferior vena cava, and aorta and fuses with the foregut mesentery to form the posterior and medial (membranous) portions of the diaphragm. • Pleuro peritoneal canals fuse • Failure of fusion --- CDH -- BUT Dr.S.Parthasarathy MD DNB PhD

9. Dr.S.Parthasarathy MD DNB PhD

10. Pathogenesis • Experimental evidence suggests that pulmonary hypoplasiaarises during the embryonic stage of gestation, prior to the development of the fetal diaphragm. • Persistant pulmonary hypertension • Transition ?? Endothelin !! Dr.S.Parthasarathy MD DNB PhD

11. How do we know ?? • One dose of the herbicide nitrofen, when administered to rodents in early pregnancy, consistently induces pulmonary hypoplasia and CDH in a high proportion of their offspring. • So pulmonary hypoplasia → CDH Dr.S.Parthasarathy MD DNB PhD

12. It is similar to films • A few people came to movies to see glamour • But now glamour is the major determinant to suck people into its fold • Pulmonary hypoplasia sucks ?? • Both sides problem in lungs – but contents worsen ipsilateral side Dr.S.Parthasarathy MD DNB PhD

13. Think as a whole • Its not a hole in the diaphragm • Many problems noted • Even sometimes – LV dysfunction is noted Dr.S.Parthasarathy MD DNB PhD

14. What is inside ?? • underdeveloped airways, • Abnormal differentiation of type II pneumocytes, • reduced number of pulmonary arteries per unit lung volume. • Intrapulmonary arteries become excessively muscularized • React to vasoactive substances Dr.S.Parthasarathy MD DNB PhD

15. Prenatal diagnosis • USG - 24 weeks – stomach in the thorax easy • But other contents and right sided may be difficult • Look for associated cardiac anomalies • Prognosis bad if other anomalies Dr.S.Parthasarathy MD DNB PhD

16. lung-thorax transverse area ratio (LT ratio) • ratio of right and left lung area to thorax area in a cardiac four-chamber view, to assess the severity of the pulmonary hypoplasia • Serial measurements – important • < 0.25 – bad • fetal lung-to-head ratio– LHR<1.0 implies a poor prognosis. Dr.S.Parthasarathy MD DNB PhD

17. Antenatal treatment • Surfactant therapy – proved use ?? • Steroids – betamethasone – beneficial • Fetoscopic repair ?? • Fetoscopic balloon occlusion of trachea • Surfactant remains and expands • At the time of delivery – unplug trachea • patients may benefit if liver is not the content Dr.S.Parthasarathy MD DNB PhD

18. After birth, can she be happy ?? • Normal or LSCS --=- NO PROBLEM • BUT BE SURE TO BE TERM Less mask ventilation Dr.S.Parthasarathy MD DNB PhD

19. Physical examination • scaphoid abdomen, • bulging chest, • decreased breath sounds • distant or right-displaced heart sounds, • bowel sounds in the chest • Cyanosis • Resp. distress . Dr.S.Parthasarathy MD DNB PhD

20. Morgagni-type hernia • Neonates with the Morgagni-type hernia may present with less severe respiratory compromise but with symptoms of bowel obstruction. Dr.S.Parthasarathy MD DNB PhD

21. bowel gas pattern in the chest, mediastinal shift Dr.S.Parthasarathy MD DNB PhD

22. Blood gas values of infants Dr.S.Parthasarathy MD DNB PhD

23. Pathophysiology • Hypoxia – tachypnea • ↓ • Hypocarbia – exhaustion • ↓ • Hypercarbia – respiratory acidosis • ↓ • Tissue hypoxia • ↓ • Metabolic acidosis Dr.S.Parthasarathy MD DNB PhD

24. Immediate intervention • decompression of the stomach with an orogastric or nasogastric tube • supplemental oxygen by mask. • No mask ventilation . • If cyanosis and hypoxemia persist, awake intubation should be done to facilitate mechanical ventilation Dr.S.Parthasarathy MD DNB PhD

25. peak inspiratory pressures should not exceed 25 cm H2O. • FIO2 should be adjusted so that preductal arterial saturations (SaO2 ) are >85%. Dr.S.Parthasarathy MD DNB PhD

26. Options • A-a PO2 gradient is more than 500mmHg is predictive of bad prognosis • 400 – 500 – doubtful • < 400 -- OK • Preductal 20 to 30 mm Hg O2 more • Shunt is where ?? – PDA or PFO • NaHCo3, ventilation , • pulm. Vasodilators (inh. NO) – more useful in Right heart failure • It corrects PHT but not hypoxia Dr.S.Parthasarathy MD DNB PhD

27. Maintain temperature • IV fluids, • Fentanyl infusion • high-frequency oscillatory ventilation (HFOV) • Not more than 15 cm – no proper trials Dr.S.Parthasarathy MD DNB PhD

28. Before surgery • Hypoxemia • Hypercarbia • Acidosis • Should be corrected before surgery • NO PPH • Emergent to intervene • But emergent to operate ?? • May wait for 7 to 10 days Dr.S.Parthasarathy MD DNB PhD

29. One more index • oxygenation index • [FIO2x mean airway pressure x 100/PaO2].) Values of oxygenation index in excess of 40 predict mortality greater than 80%. • 0.5 * 25 * 0.5 • = 6.25 Dr.S.Parthasarathy MD DNB PhD

30. Extracorporeal membrane oxygenation • Yes useful if IPPV fails • Veno venous and veno arterial • Membrane oxygenator • Beware of heparin in ECMO • But long term survival and morbidity were worse in those cases Dr.S.Parthasarathy MD DNB PhD

31. ECMO Dr.S.Parthasarathy MD DNB PhD

32. Other bad prognostic indicators 1. symptoms severe enough to require intubation immediately after birth 2) <1000g 3)< 33 weeks gestational age 4) PaCo2 > 50 mm Hg Dr.S.Parthasarathy MD DNB PhD

33. Anaesthetic options Dr.S.Parthasarathy MD DNB PhD

34. Specific problems of neonates: • Anatomical problems : difficult venous and difficult airway access • - Physiological problems : high metabolic rate, limited pulmonary, cardiac and thermo regulatory reserve , impaired renal and hepatic function. • - Pharmacological problems: • multi-system immaturity contrast to adult • RAVI • ( reserve, rate, airway, venous, immaturity) Dr.S.Parthasarathy MD DNB PhD

35. B- Specific problems of prematurity (less than 37 weeks) • - Perioperativehypoglycemia. – • Hypothermia. • Intracranial haemorrhage • - Congestive heart failure. • Retinopathy. • - Respiratory distress. • HHHH RR - pneumonic Dr.S.Parthasarathy MD DNB PhD

36. As Prof. mentions In neonates -- Take care of • oxygenation, • Temperature • IV fluids Dr.S.Parthasarathy MD DNB PhD

37. Anaesthetic management • Laboratory tests • ABG, CBC, electrolytes, blood sugar, blood type, and cross-match for blood products. • Temperature corrected • Upper limb IV access √ – reduction of hernia may obstruct IVC Dr.S.Parthasarathy MD DNB PhD

38. Premed and monitors • No premedication • Monitors for • RS, ( pre and postductal SPO2) • CVS ( CVP- preferably femoral access ) • Temperature Dr.S.Parthasarathy MD DNB PhD

39. Induction • Awake intubation • Sevo induction and intubation • Relaxant ?? • No problem if already intubated by paediatrician • No nitrous before reduction – Air -O2- agent • Ventilate – high frequency, 25 – 30 cm pressure • Permissive hypoxemia Dr.S.Parthasarathy MD DNB PhD

40. Again it’s the same In neonates -- Take care of • oxygenation, • Temperature • IV fluids • IV fentanyl 1 – 3 Mic gm / kg Dr.S.Parthasarathy MD DNB PhD

41. Intraop problems • Closure • Sudden hypotension and desaturation • 1. tension pneumothorax – contralateral – ICD • 2. IVC compression – silastic patch closure • Pneumothorax can also happen ipsilaterally Dr.S.Parthasarathy MD DNB PhD

42. The basic fluid schedule • 5% dextrose in one-fourth to one-half strength saline are given at 4 mL/kg/hour. • Intraoperative evaporative and third space losses are replaced with Ringer's lactate or saline at approximately 6 to 8 mL/kg/hour. • Each milliliter of blood loss is replaced with 3 mL of Ringer's lactate or 1 mL of 5% albumin Dr.S.Parthasarathy MD DNB PhD

43. Do not extubate • But beware of transport Dr.S.Parthasarathy MD DNB PhD

44. Can go bad again • Pulmonary hypoplasia • Associated congenital defects • Inadequate preoperative preparation. • Pneumothorax Ineffective postoperative management. Hemorrhage, tension pneumothorax, inferior vena cava compression, persistent fetal circulation, excessive suction on chest tube Dr.S.Parthasarathy MD DNB PhD

45. 30 – 60 % mortality Dr.S.Parthasarathy MD DNB PhD

46. Long-term follow-up • Gastroesophageal reflux occurs in up to 62% of patients, • 56% are below the 25th percentile for weight • 32% require a gastrostomy, • 19% require fundoplication Dr.S.Parthasarathy MD DNB PhD

47. Summary • Definition • Incidence • Types • Prenatal • Bad prognosis • Pre anaesthesia • Anaesthesia • Post op Dr.S.Parthasarathy MD DNB PhD

48. Thank you all Dr.S.Parthasarathy MD DNB PhD