Transcript Slide 1

Complications of
Neonatal Surgical
Cases:
NEC and Birth Defects
Dr. Phillip Pan, MD
Neonatologist
Bellevue Woman’s Center, a service of Ellis Medicine
Albany Medical Center
Complications of Neonatal
Surgical Cases: Objectives
• Necrotizing Enterocolitis
• Birth Defects
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Tracheoesophageal Fistula
Myelomeningocele
Abdominal wall defects (gastroschisis, omphalocele)
Hydrocephalus (congenital, post-hemorrhagic)
• Gastrostomy tube
Necrotizing
Enterocolitis
• Characterized by injury to the intestines with variable
degrees of intestinal ischemia, usually including the
terminal ileum
• Gas develops within the muscular and submucosal
layers and may be seen as pneumatosis intestinalis
• When full-thickness necrosis occurs, perforation and
peritonitis develop
Characteristics
• 1-5% of all NICU admissions
• usually onset between 3rd - 10th day of life
• no association between sex, race, season or
socioeconomic status
• predominantly affects premature infants, but about
10% of those affected are term infants
• mortality is between 30-40%
Theories
• Variable theories – infection, inflammation,
ischemia/reperfusion injury
• Probably multifactorial and requires
interaction of immaturity, previous
gastrointestinal ischemia, enteral feeding and
bacterial invasion
• Contradicting the theory is NEC occurs in
infants
• with no identifiable risk factors,
• who were never fed enterally, and
• among otherwise healthy full-term infants
Bell Clinical Staging
• Stage I – Suspected NEC
• Temp instability, apnea, gastric residuals, abdominal
distension. No radiographic abnormalities
• NPO, antibiotics for 2-3 days pending culture
• Stage II – Definite NEC
• Also includes absent bowel sounds, abdominal
tenderness
• Ileus, pneumatosis (see photo)
• NPO, antibiotics x14 days
A plain anteroposterior radiograph demonstrating pneumatosis
Dimmitt, R. A. et al. Neoreviews 2001;2:110-e117
Copyright ©2001 American Academy of Pediatrics
Bell Clinical Staging
Stage III – Advanced NEC
• hemodynamic instability, DIC, neutropenia,
metabolic acidosis, respiratory compromise
• generalized peritonitis, marked tenderness and
distension of abdomen
• antibiotics, inotropes, assisted ventilation
• Includes bowel perforation,
pneuomoperitoneum
An anteroposterior radiograph showing extensive pneumatosis and free air
Dimmitt, R. A. et al. Neoreviews 2001;2:110-e117
Copyright ©2001 American Academy of Pediatrics
Surgical
Management
• Indications include pneumoperitoneum,
persistent metabolic acidosis, rapidly
worsening pulmonary status and unremitting
neutropenia or thrombocytopenia
• Emergently a peritoneal drain may be placed
• Staged exploratory laporatomies to identify
ischemic, perforated, and necrotic bowel
Complications
• stricture formation occurs in 25-35% of survivors
• “silent” strictures may be identified by barium enema
• late-onset intestinal obstruction following medical and/or
surgical management includes adhesions, scarring and
short bowel syndrome
• neurodevelopmental delays occur in 50% of
survivors
• most serious intestinal complication is short bowel
syndrome (25%)
Short Bowel
Syndrome
• NEC is the leading cause of SBS
• other causes include congenital malformations
• More than 50% of small bowel must be removed
before substantial malabsorption occurs
• normal lengths - 150 cm at 28 weeks vs 250 cm at term
• an important determinant of future function is presence of
ileocecal valve
• 20 cm is minimal length sufficient to allow dependence on
TPN
• following ileocolic anastomasis, painless rectal
bleeding or melena from anastomotic ulcers can occur
years after NEC surgery
Prognosis
• prognosis of patients with short bowel syndrome is guarded
• infants are followed by the primary physician, pediatric
gastroenterologist and surgeon
• Some of these complications may be present at discharge from the
NICU, and some require continued surveillance
• Poor growth is a frequent outcome
• Dumping syndrome is observed in infants with ostomies or severe
diarrhea during GI infections
• Dumping syndrome may cause rapid dehydration and electrolyte
imbalance
Changing Pattern of Causes
and Mortality of SBS
Date of
Report
Study
size
Intestinal
Anomalies : NEC
(%)
Mortality
Rate(%)
Reference
1972
50
100 : 0
32
1986
-
71 : 29
-
1998
34
56 : 44
12
Sondheimer
2001
30
57 : 43
30
Andorsky
2004
78
80 : 20
27
Zuiros-Tejeira
2008
19
56 : 44
11
Salvia
2008
89
4 : 96
50
Cole
Wilmore
Ziegler
Bowel and Liver
transplantation
• Boston Children’s Hospital
• Children Hospital of Philadelphia
• New York city
• 105.09 liver transplantation - for 1 year following the
date of transplantation
TPN-related
cholestasis
• Characterized by direct hyperbilirubinemia,
hepatomegaly and increased serum transaminases
• Risk factor includes prolonged enteral fasting
• Treatment includes enteral nutrition, increasing bile
acid production (actigall, phenobarbitol) and stopping
TPN
Gastrostomy tube
• Anatomic, neurologic and developmental disorders
• Memorable cases
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Congenital myotonic dystrophy
Pierre Robin sequence
Tracheo-esophageal fistula
Severe bronchopulmonary dysplasia
• 105.10 - Need for supplemental daily enteral feeding
via a g-tube for children < 3 years
Gastrostomy tube
Mickey button
G-tube for GER
• some children who have antireflux surgery also benefit
from a G-tube
• G-tube should be considered in children with
neurologic impairment, poor gastric motility, or poor
nutritional status
• In addition to facilitating postoperative feeding, it
allows drainage or venting of the stomach
Birth Defects:
outline
• Tracheoesophageal Fistula
• Myelomeningoceles
• Abdominal wall defects
• Gastroschisis
• Omphalocele
• Hydrocephalus
• Congenital
• Post-hemorrhagic
Birth Defects
• An abnormality of
structure, function or
metabolism that results in
physical or mental
disabilities or death
• 3% of all children
(120,000 babies) are born
with a serious structural
defect
• The leading cause of
death in the 1st year of life
Tracheoesophageal
Fistula
Surgical Repair of
TEF
• Surgical repair depends on presence of esophageal
atresia, gap between proximal and distal esophagus
ends, degree of respiratory compromise
• Initial timing must consider aspiration of gastric
contents into the lower lungs with urgent
decompression and ligation of the distal TEF
• May involve gastric pull-up, colonic graft, gastrostomy
tube
Complications
• Early – anastomotic leak, recurrent TEF and
anastomotic strictures
• Late – GER, esophageal dysmotility and
tracheomalacia
Outcome and
Prognosis
• Statistics are constantly changing and improving
• Mortality ranges from 7-63% and 0-11% depending on
classification technique and reporting statistics
• Fetuses with prenatal diagnoses of esophageal atresia
have a worse prognosis with a mortality rate as high as
75% vs 21 % without esophageal atresia
Omphalocele vs
gastroschisis
Omphalocele
Gastroschisis
Pathogenesis
Abnormality during
body folding
Compromise of
vascular supply
Etiology
Sporadic. Increased
assoc with genetic
syndrome
Sporadic. Increased
assoc with young
mothers
Birth weight (< 5th %ile) 20%
77%
Mortality at 1 yr
40%
7.7%
PE
AGA infant, enclosed
sac, may include liver
and other organs
SGA infant, exposed
intestines.
Management of
Open Ventral Wall Defects
• Multidisciplinary teamwork
• Protect exposed bowel/mucosa
• Prevent heat loss
• Prevent insensible water loss
• Prevent vascular compromise
• Nasogastric decompression
• Broad-spectrum antibiotic coverage
• Total parenteral nutrition
• Surgical correction
Gastroschisis
Compromised bowel
Omphalocele
Large with wharton jelly
Bowel in silo
Neural Tube defects
• Neural tub defects affect about 3000 pregnancies each
year in the US
• Risk may be reduced by taking at least 0.4 mg of
vitamin B folic acid before and during early pregnancy
• The neural tube folds inward to form a tube by the 28th
day after conception
• Includes spina bifida, anencephaly, encephalocele
Spina Bifida
• The most common NTD, affect 1500 babies each year
in the US
• 3 classic forms
• Occulta – mildest form with usually no symptoms
• Meningocele – rarest from with just cyst or fluid-filled sac
without spinal nerves
• Myelomeningocele
Myelomeningocele
• both the membranes and nerve roots of the spinal cord
are enclosed in cyst or fully exposed
• In spite of surgical repair, affect babies have some
degree of leg paralysis, encoparesis and eneuresis
Hydranencephaly
Classic Dandy-Walker
variant
Melissa A. Parisia and William B. Dobyns. Human malformations of the midbrain and hindbrain: review
and proposed classification scheme. Molecular Genetics and Metabolism. 80 (2003): 36–53.
Dandy-Walker Variants
Incidence of IVH
• 34 - 49% LBW infants in 1970’s
• 20 - 29% LBW infants in 1980’s
• Incidence correlates with degree of prematurity
• Survival rates of smallest infants continue to increase
Risk of IVH
• Risk is inversely proportional to gestational age
• 35% of infants with birth weights of 500-600 g have
grade 3 or 4 IVH
• If posthemorrhagic ventricular dilatation occurs after
intraventricular hemorrhage does, it is usually apparent
on cranial ultrasonography within 2-3 weeks
• Infants who have had intracranial hemorrhage must
always be monitored in neurodevelopmental follow-up
clinics
IVH: Grade I
IVH Pathology
IVH Pathology Severe bleed
Outcomes for IVH
• ELBW preterm infants with grade I or II IVH
may have poor neurodevelopmental outcomes
• Grade III or grade IV IVH is associated with
the least favorable neurodevelopmental results
• the degree of prematurity and the presence of
chorioamnionitis may also be major contributors to
severe long-term disabilities
• IVH may lead to posthemorrhagic
hydrocephalus
Post-hemorrhagic
Ventricular Dilation
• 65% no progressive ventricular dilation
• Majority of infants with slight/moderate IVH
• Minority of infants with severe IVH
• 35% slowly progressive ventricular dilation
• 65% spontaneous arrest within 4 weeks with some or
complete resolution
• 30% continue to progress > 4 weeks, 1/3 of these
become rapid
• 5% rapidly progress < 4 weeks
Outcomes for
PHH/PVL
• parenchymal hemorrhage causes cerebral infarction
and can lead to cerebral or cerebellar porencephaly
• Porencephaly and posthemorrhagic hydrocephalus are
among the most devastating CNS events in premature
infants.
• Cystic PVL
• High risk for CP
• Cognitive delays in children with severest lesions on u/s and
with spastic quadriplegia
Ventriculo-peritoneal shunt
• Although ventricular dilatation may be reversible, infants with
severe ventricular enlargement are at high risk for
neurodevelopmental handicap
• Rapidly progressive posthemorrhagic hydrocephalus may require
permanent placement of a cerebrospinal fluid (CSF) shunt
• The long-term neurodevelopment of ELBW infants who require
shunt insertion is very unfavorable compared with ELBW infants
with intraventricular hemorrhage who do not have ventricular
enlargement
• head circumference should be monitored for rapid or slow growth
Shunt Malfunction
• the NICU graduate with a VP shunt must be
monitored for for shunt infections or malfunctions
• Malfunctions are typically due to an occlusion of the
proximal or distal cannula with a subsequent increase
in intracranial pressure
• Poor feeding, vomiting, irritability, lethargy, sleepiness,
apnea, and seizures
• shunt infection and meningitis should be suspected
with fever and malaise
PVL sequelae
• Other postnatal events leading to PVL include CSF infections or
intraventricular hemorrhage, life-threatening apnea and
bradycardia, and cardiorespiratory arrest
• The condition is otherwise identified on cranial sonograms as
echogenic areas in the periventricular white matter. Injuries in
these areas evolve into cysts
• PVL is highly associated with subsequent neurodevelopmental
disabilities, particularly cerebral palsy
• Persistence of cysts is known to increase the risk of severe
neuromotor abnormalities