congenital diaphragmatic hernia dr. s. parthasarathy md., da., dnb, md (acu), dip. diab.dca, dip....
TRANSCRIPT
Dr.S.Parthasarathy MD DNB PhD
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
What is it ??
• Herniation of abdominal contents in the
thoracic cavity through a cong defect in the
diaphragm
Dr.S.Parthasarathy MD DNB PhD
How common ??
• Incidence:-• 1 in 2000 to 1 in 4000
• M:F : 2:1
• Lt : Rt : 5:1
Dr.S.Parthasarathy MD DNB PhD
Sites
80 % 10 %
Dr.S.Parthasarathy MD DNB PhD
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
Aetiology
• Unclear • 2 % familial • Genetic association - trisomies 13, 18 and 21.• Chromosome region 15q26 – necessary for
diaphragm development
Dr.S.Parthasarathy MD DNB PhD
40 % associated with other anomalies • Cardiac anomalies• Ductus arteriosus Septal 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
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
Dr.S.Parthasarathy MD DNB PhD
Pathogenesis
• Experimental evidence suggests that pulmonary
hypoplasia arises 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
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
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
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
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
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
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
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
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
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
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
bowel gas pattern in the chest, mediastinal shift
Dr.S.Parthasarathy MD DNB PhD
Blood gas values of infants
Dr.S.Parthasarathy MD DNB PhD
Pathophysiology
• Hypoxia – tachypnea • ↓• Hypocarbia – exhaustion • ↓• Hypercarbia – respiratory acidosis • ↓• Tissue hypoxia • ↓• Metabolic acidosis
Dr.S.Parthasarathy MD DNB PhD
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
• 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
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
• 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
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
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
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
ECMO
Dr.S.Parthasarathy MD DNB PhD
Other bad prognostic indicators
1. symptoms severe enough to require intubation immediately after birth
2) <1000g3)< 33 weeks gestational age4) PaCo2 > 50 mm Hg
Dr.S.Parthasarathy MD DNB PhD
Anaesthetic options
Dr.S.Parthasarathy MD DNB PhD
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
B- Specific problems of prematurity (less than 37 weeks)
• - Perioperative hypoglycemia. – • Hypothermia.• Intracranial haemorrhage• - Congestive heart failure. • Retinopathy.• - Respiratory distress.
• HHHH RR - pneumonic
Dr.S.Parthasarathy MD DNB PhD
As Prof. mentions
In neonates -- Take care of
• oxygenation, • Temperature • IV fluids
Dr.S.Parthasarathy MD DNB PhD
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
Premed and monitors
• No premedication
• Monitors for • RS, ( pre and postductal SPO2)• CVS ( CVP- preferably femoral access )• Temperature
Dr.S.Parthasarathy MD DNB PhD
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
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
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
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
• Do not extubate
• But beware of transport
Dr.S.Parthasarathy MD DNB PhD
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
• 30 – 60 % mortality
Dr.S.Parthasarathy MD DNB PhD
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
Summary
• Definition • Incidence • Types • Prenatal • Bad prognosis • Pre anaesthesia • Anaesthesia • Post op
Dr.S.Parthasarathy MD DNB PhD
Thank you all