Transcript Neonatal Emergencies

Peadiatric surgery
emergencies
{
Yanal Abaza.MD
*Pyloric Stenosis
* Congenital Diaphragmatic
Hernia
*Tracheoesophageal Fistula
*Abdominal Wall Defects
*Necrotizing Enterocolitis
(NEC)
Preoperative Evaluation
• Maternal and perinatal history
• Recreational drug use
• Birth history
• Minimum labs: glucose and CBC
• Look for associated anomalies
• Cardiac and respiratory status
• Metabolic and electrolyte imbalance
• Hydration status
• Coagulation profile
• IV access
Pyloric Stenosis
Pyloric Stenosis
Most common GI obstructive anomaly in neonates
Hypertrophy of the muscular layer of the pylorus
A medical emergency but not a true surgical
emergency
Incidence: 1 – 3 :1,000 live births
2 - 5x more common in first born, M > F (4:1)
Etiology : unknown
? acquired condition with hereditary
predisposition
Symptoms are apparent between 2nd-6th wk of
life
Presents with nonbilious projectile vomiting,
signs of dehydration, jaundice (2%)
Pyloric Stenosis
Pyloric Stenosis
Physical Exam
visible gastric peristalsis
palpable “olive-shaped” mass to the right
of the epigastric area
signs of dehydration
Labs: CBC
serum electrolytes
ABG
EKG
BUN
Pyloric Stenosis
Diagnosis
history and physical exam
abdominal ultrasound
upper GI series with barium contrast
not recommended
pathological
pyloric wall thickness ≥ 4 mm
pyloric length of > 16 cm
Pyloric Stenosis
Metabolic Abnormalities
• hyponatremia
• hypochloremia
• hypokalemia
• 1° metabolic alkalosis
• compensatory respiratory acidosis
• paradoxical acidic urine
Pyloric Stenosis
Preoperative Preparation
supportive treatment
surgical management
check labs
Pyloric Stenosis
Preoperative Preparation
Supportive therapy
• Correction of fluid deficits
maintenance: D5 0.2% NaCl + KCl
20 - 40 mEq/L
replacement: albumin, normal saline
• Correction of electrolyte imbalance
• Prevention of aspiration : NGT
Surgical Management
Pyloromyotomy
definitive treatment
open or laparoscopic
Lab indices for safe anesthesia
Pyloric Stenosis
serum Cl >100 mEq/L
HCO3 < 28 mEq/L
Pyloric Stenosis
Concerns :
* pulmonary aspiration
* severe dehydration
* metabolic alkalosis
Congenital Diaphragmatic
Hernia
Congenital Diaphragmatic Hernia
Herniation of abdominal viscera into the thorax
Result from failure of the pleuroperitoneal canal
to close at ~ 8th wk of gestation or early
return of midgut to the peritoneal cavity
Most challenging and frustrating of all neonatal
surgical emergencies
Congenital Diaphragmatic Hernia
50% mortality regardless of the method of
treatment
Incidence: 1:2,000-5,000 live births
M<F 1:1.8, frequently full term
Etiology: unknown
no genetic factors have been implicated
Antenatal history: polyhydramnios
Congenital Diaphragmatic Hernia
Classification
• Absent diaphragm : rare
• Diaphragmatic hernia
80% posterolateral L >R
(Bochdalek)
2% anterior (Morgagni)
15 - 20% paraesophageal
• Eventration (15 - 20%)
Congenital Diaphragmatic Hernia
Associated anomalies (20-50%)
cardiovascular
13 - 23%
CNS
28%
gastrointestinal
20%
genitourinary
15%
• increase the mortality rate
Congenital Diaphragmatic Hernia
Classic Triad
Dyspnea
Cyanosis
Apparent dextrocardia
Congenital Diaphragmatic Hernia
Physical Exam
scaphoid abdomen and barrel chest
bowel sounds in the chest
displaced heart sounds
Laboratory Studies
CBC
ABG
electrolytes
calcium
glucose
Congenital Diaphragmatic Hernia
Diagnosis: chest x-ray
• loops of bowel in the
chest
• mediastinal shift
• absent lung markings
Congenital Diaphragmatic Hernia
IMMEDIATE
Intubation
+
Stomach Decompression
Congenital Diaphragmatic Hernia
Determinants of Survival
• degree of pulmonary hypoplasia
ipsilateral lung > contralateral lung
• development pulmonary vasculature
Congenital Diaphragmatic Hernia
Goals of Management
• maximize arterial oxygenation
mechanical ventilation: use low inflating
pressures
increases pulmonary blood flow
• prevention of pain
fentanyl infusion 3-10 mcg/kg/hr
• correction of acidosis
Congenital Diaphragmatic Hernia
Standard Management Strategy
Reduce pulmonary HTN
Moderate alkalosis
pCO2 < 40 mmHg
PaO2 >100 mmHg
Congenital Diaphragmatic
Hernia
Recent Strategy
• Permissive hypercapnia and hypoxemia
• Pressure-limited ventilation (<25 cmH2O)
• Postductal pCO2 40-65 mmHg
• Preductal SpO2 85-90%
• Postductal SpO2 ignored unless pH is
< 7.20 or pCO2 > 65
Congenital Diaphragmatic Hernia
Bohn (1986)
reevaluation of the traditional “mad dash”
surgical strategy
recommended 24 – 48 hrs medical stabilization
assessment of efficacy of delayed approach
infants unresponsive to initial therapy will fail to
survive with surgery or any other treatment
including ECMO
Congenital Diaphragmatic Hernia
The Relationship Between PaCO2 and Ventilation
Parameters in Predicting Survival in CHD
• Arterial CO2 accurately reflects the degree of
lung development
• Poor survival in the presence of severe
pulmonary hypoplasia
• CO2 retention and severe preductal shunting
have 90% mortality
Bohn, DJ, et al
J of Pedia Surg 19: 666-671, 1884
Congenital Diaphragmatic Hernia
nomogram:
to predict the degree of pulmonary hypoplasia in
the infants and chance of survival
used the preop PaCO2 and an index of ventilation
(Vi)
If PaCO2 < 40 and Vi < 1000: survival almost universal
If PaCO2 > 40 and Vi > 1000: death virtually inevitable
Vi = mean airway pressure x respiratory rate‫٭‬
Congenital Diaphragmatic Hernia
Acid Base Balance and Blood Gases in
Prognosis and Therapy of CHD
High Mortality
pH < 7.0
pCO2 >60 mmHg
pO2 < 50 mmHg
Boix-Ochoa J, et al
J Pediatric Surg 9:49-57, 1974
Congenital Diaphragmatic Hernia
Indications of Surgical Repair
• Reversal of ductal shunting
• O2 index of < 40
• Arterial pCO2 maintainable under
40 mmHg
• Hemodynamic stability
Congenital Diaphragmatic Hernia
Preoperative Preparation
• Look for associated anomalies
• Labs: CBC, electrolytes, ABG, glucose,
blood type and crossmatch
• CXR, Echo
• Venous access: upper extremities
preferred
• Prevention of hypothermia
Congenital Diaphragmatic Hernia
Intraoperative
Surgical repair
primary closure
staged procedure
Transabdominal subcostal incision
Thoracoscopic repair has been reported
Congenital Diaphragmatic Hernia
Intraoperative
Potential Problems
• Hypoxemia
distension of stomach
1° pulmonary hypoplasia / pulmonary HTN
• Contralateral pneumothorax
• Hypotension or IVC compression
• Cardiac arrest
Congenital Diaphragmatic Hernia
Postoperative Care
Ventilatory support
Close fluid management
Hemodynamic monitoring
“Honeymoon Period” followed by deterioration
increase abdominal pressure
impaired peripheral and visceral perfusion
limited diaphragmatic excursion
worsening of pulmonary compliance
Tracheoesophageal
Fistula
Tracheoesophageal Fistula
Incidence: 1:4000 live births
M > F (25:3)
10-40% are preterm
Antenatal history: polyhydramnios (60%)
Etiology: failure in mesenchymal separation of
upper foregut
Tracheoesophageal Fistula
Clinical Presentation
choking on 1st feed
coughing
cyanosis
excessive salivation
aspiration pneumonia
Tracheoesophageal Fistula
Diagnosis
• inability to pass a suction catheter
into the stomach
• CXR: coiled orogastric tube in the
cervical pouch; air in the stomach
and intestine
Tracheoesophageal Fistula
Esophageal Atresia
Tracheoesophageal
Fistula
Turnage RH, et al, Sabiston Textbook of Surgery,17th Ed. 2004
TracheoEsophageal Fistula
5 Types (Gross and Vogt)
7.7%
0.8%
86%
0.7%
4.2%
Gregory GA, ed, Pediatric Anesthesia, 3rd edition, 1996
Tracheoesophageal Fistula
35-65% have associated anomalies
VATER and VACTERL
V
vertebral anomalies or VSD
A
anorectal malformation
C
cardiac anomalies (common)
T
TEF
E
esophageal atresia
R
renal abnormalities
L
limb/radial malformation
Tracheoesophageal Fistula
Preoperative Preparation
Minimize pulmonary complication
npo
head-up position
sump tube (repogle) on low continuous suction
± gastrostomy under local anesthesia
CXR, abdominal x-ray, renal ultrasound
12-L EKG and Echocardiogram : mandatory
IV access ± arterial line
Tracheoesophageal Fistula
Preoperative Preparation
Laboratory studies
CBC
Electrolytes
Glucose
Calcium
ABGs
Tracheoesophageal Fistula
Preoperative Preparation
24-48 hr medical stabilization
Antibiotics: ampicillin and gentamicin
Ensure availability of blood in the OR
Optimize volume status and metabolic state
Intubation preferably in the operating room
under controlled situation
Tracheoesophageal Fistula
Intraoperative Management
Main Concern
oxygenation and ventilation
securing the airway
Monitors
ASA standard
± invasive : arterial line
Tracheoesophageal Fistula
Intraoperative Management
Surgical repair
• ligation of fistula
check air leak in suture line
• esophageal repair
identify the pouch
placement of feeding tube
• chest tube placement and closure of
thoracic cavity
Tracheoesophageal Fistula
Postoperative Management
Early extubation desirable
caution: disruption of surgical repair with
reintubation
Postop Pain Management
1. IV narcotics
2. epidural infusion: 0.1% bupivacaine +
fentanyl 0.5 mcg/ml at 01.-0.2 ml/kg/hr
3. rectal Tylenol + LA infiltration of incision
Tracheoesophageal Fistula
Main Cause of Mortality
associated anomalies
survival rates 85-90%
Long Term Complications
GE reflux
anastomotic stricture
tracheomalacia
Abdominal Wall
Defects
Gastroschisis
Omphalocoele
Gastroschisis
Greek word for “belly cleft”
Evisceration of gut through a 2-3 cm defect in
the anterior abdominal wall lateral to the
umbilicus, usually on the right
Absence of covering or sac
chemical peritonitis
infection
ECF loss
heat loss
Incidence: 1:15,000-30,000 live births
Gastroschisis
Gastroschisis
Etiology
exact cause unknown
Theories
• intrauterine occlusion of omphalomesenteric artery → ischemia and
atrophy of abdominal muscles
• early fetal rupture of an omphalocoele
Gastroschisis
• rupture of umbilical cord at the site
of the resorbed right umbilical vein
• ? Maternal: smoking, ETOH,
recreational drugs, medications
(NSAIDS, pseudoephredrine)
• associated anomalies - rare
Omphalocoele
Omphalocoele
External herniation of abdominal viscera into
the base of the umbilical cord through a
central defect
Defect: small or large
Umbilical cord is inserted into the apex of the
lesion
Presence of covering or sac (amnion and
peritoneum)
Incidence: 1-5,000-10,000 live births
Omphalocoele
Embryology
Failure of the midgut to return to the
abdominal cavity by the 10th wk of
gestation
Omphalocoele
Omphalocoele
Etiology
• incomplete return of the gut to the
abdominal cavity due to an abdominal
lateral fold defect
• Failure of migration and fusion of cranial,
caudal and/or lateral folds of the embryonic
disc at ~ 3rd wk of gestation
Omphalocoele
Cranial Fold : Pentalogy of Cantrell
Epigastric omphalocoele
Sternum cleft
Diaphragmatic defect
Ectopia cordis
Cardiac anomaly
Omphalocoele
Lateral Fold
omphalocoele with cord coming of the
center of the sac
Caudal Fold
Hypogastric omphalocoele
Extrophy of the bladder
Imperforate anus
Colonic agenesis
Vesicointestinal fistula
Omphalocoele
Associated Congenital Anomalies: 75-80%
chromosomal: trisomy 13, 15, 21
cardiac anomalies: 20%
craniofacial
gastrointestinal
Beckwith-Wiedeman Syndrome
omphalocoele
microcephaly
visceromegaly
hypoglycemia
macroglossia
hyperviscosity
Pentalogy of Cantrell
Omphalocoele
Survival: 20% with heart disease
70% without heart disease
Major cause of mortality
cardiac defects
prematurity
Definitive Treatment: surgical repair
Incidence
Peritoneal
covering/sac
Location of
defect
Herniated
bowel
Associated
anomalies
Gastroschisis
Omphalocoele
1:15,000-30,000
1:6,000
absent
present
periumbilical
matted, edematous
low (10-15%)
intestinal atresia
(15%)
within the umbilical
cord
normal
high (40-60%)
congenital heart dis.
Beckwith-Weidman
syndrome
Gastroschisis
Omphalocoele
Abdominal Wall Defects
Preoperative Management
• Hydration / fluid status
warm moist sterile saline-soaked gauze
plastic bowel bag
initial fluid requirement 10 -15 ml/kg/hr; higher with
gastroschisis 100-200 ml/kg/hr
• Heat loss : neutral thermal environment
• Difficulties of surgical closure
• Associated congenital anomalies & prematurity
Abdominal Wall Defects
Preoperative Management
• Infection and postop nutrition
• Postoperative ventilation
• Airway
• Metabolic status
• Aspiration precautions
• Direct trauma to herniated organ
Abdominal Wall Defects
Preoperative Management
Lab workup
CBC
Electrolytes and Glucose
ABG
CXR
Echocardiography
Abdominal Wall Defects
Intraoperative Management
Prevent hypothermia
full access body hugger
heating blanket
increase room temp
plastic wrap
fluid warmer
Fluid requirement
maintenance: D5 0.2% NS
3rd space loss replacement
isotonic fluid 10 -15 ml/kg/hr
blood loss from adhesions
Abdominal Wall Defects
Intraoperative Management
Surgical Closure
• optimal method remains controversial
1) primary fascial closure : 80%
± intraop and postop muscle paralysis
2) staged repair
silicone elastometer pouch
primary skin closure
Abdominal Wall Defects
Intraoperative Management
• Closure dependent on the
1) size of the defect
2) development of abdominal wall
3) presence of associated anomalies
Abdominal Wall Defects
Intraoperative Management
Unsafe for Primary Abdominal Closure
• Intragastric pressure > 20 cmH2O
• Intravesical pressure > 20 cmH2O
• Change in CVP 4 ≥ mmHg
Abdominal Wall Defects
Intraoperative Management
Staged Reduction
• Dacron reinforced silastic silo
• Gradual reduction over 1- 2 weeks
• Ketamine or opioid ± muscle relaxant in
intubated patients or
• Titration of ketamine 0.5 -1 mg/kg IV with
spontaneous breathing unintubated infants
• Final closure in the OR
Abdominal Wall Defects
Intraoperative Management
Silo closure
Necrotizing Enterocolitis
(NEC)
Necrotizing Enterocolitis (NEC)
Life-threatening intestinal inflammation
or injury
Caused by bacterial invasion of previously
injured or ischemic bowel wall
Incidence: 5 -10% in infants <1500g birth
weight
Mortality rate: 10 - 30%
Necrotizing Enterocolitis (NEC)
Single most important factor
PREMATURITY
Can occur in:
premature infants
LBW infants
Full term infants
fed and unfed infants
Necrotizing Enterocolitis (NEC)
Other factors
ischemia
bacterial infection
GI endotoxemia
enteral feeding
use of hyperosmolar formula
congenital heart disease
hx of umbilical arterial catheterization
hx of exchange transfusion
Necrotizing Enterocolitis (NEC)
Early signs
↑ gastric residuals with feedings
temperature instability
poor feeding
bilious vomiting
lethargy
mucoid or bloody stool
apnea and bradycardia
Necrotizing Enterocolitis
Late Signs
Hemodynamic instability
Anemia
Thrombocytopenia
Coagulopathy, DIC
Prerenal azotemia
Metabolic acidosis
Necrotizing Enterocolitis (NEC)
Physical Exam
distended and tender abdomen
Labs:
CBC
electrolytes and glucose
platelets and coagulation profile
DIC profile
ABG
Necrotizing Enterocolitis (NEC)
Abdominal X-ray
• signs of bowel obstruction
• ileus with edematous
bowel
• Pneumatosis intestinalis
or intramural air (arrow)
• portal vein air
• pneumoperitoneum
Necrotizing Enterocolitis (NEC)
Medical Management
initial treatment, for 7-10 days
75% successful
Surgical Treatment
10 - 50% mortality
Necrotizing Enterocolitis (NEC)
Medical Management
• No enteral feedings for 10-14 days
• NGT on intermittent suction
• Hydration and correction of electrolytes
• Ventilatory support
• Antibiotics
• Blood and platelet transfusion if needed
Necrotizing Enterocolitis (NEC)
Surgical Indications
• Absolute Indications
1) bowel perforation
peritoneal drains under
local anesthesia
2) intestinal gangrene
Necrotizing Enterocolitis (NEC)
• Relative Indications
• clinical condition
metabolic acidosis
respiratory failure
oliguria, hypovolemia
thrombocytopenia
leucopenia, leukocytosis
• air in the portal vein
• bowel wall edema
• persistent dilated bowel loops
Necrotizing Enterocolitis
• Non-Surgical Indications
severe GI hemorrhage
abdominal tenderness
intestinal obstruction
gasless abdomen with ascites
Necrotizing Enterocolitis (NEC)
Preoperative Management
• Electrolyte imbalance: hyperkalemia
• Coagulopathy: thrombocytopenia
• Respiratory failure
• Sepsis / hemodynamic instability
inotropic support
dopamine infusion
Summary
• Almost all neonatal surgical “emergencies”
are really “urgencies”
• Immaturity of organ system in neonates
alters pharmacology and physiology
• Thorough preop assessment is required in
all neonates
• One anomaly mandates a search for others
• Murmurs necessitate a cardiology consult
• Successful perioperative outcome depends
on open communication and teamwork
between neonatologist, anesthesiologist and
surgeon
• Initial resuscitation of neonatal surgical
candidates includes:
airway protection
adequate IV access
fluid resuscitation
temperature stabilization
gastric decompression
administration of antibiotics
identify associated anomalies
Thank you