Title: Neonatal Surgery PrinII Juan E Gonzalez, CRNA, MS, ARNP
1Neonatal SurgeryPrin-IIJuan E Gonzalez, CRNA,
MS, ARNP
- Based on prior lecture by
- John P. McDonough, CRNA, Ed.D., ARNP
- Professor Director
- Anesthesiology Nursing
2Anatomical Differences
3Pedi vs. Adult Airway
4Head Position
Visual Alignment of Oral/Pharyngeal/Laryngeal axes
Attempt to achieve sniffing position will
OBSTRUCT pt
5Intubation
- Anterior position of larynx large tongue
- Mask ventilation more difficult than adults
- Neck/Shoulder roll (compensate for large occiput)
- Smaller potential submental space in which to
displace tongue during laryngoscopy - Straight blade preferred
6A little trick
7To intubate or not to intubateIs that a
question??
- Most clinical situations require ETT d/t anatomic
physiologic considerations - If anesthesia provided is skillful surgery is
short and no need for relaxation ? mask
ventilation or LMA could be considered - Controlled vs. Spontaneous Ventilation??
- If healthy pt short Sx ? spontaneous
ventilations acceptable - If debilitated pt, long-standing dz, circulatory
instability muscle relaxation needed for Sx ?
controlled ventilation is only choice
8Choice of Intubating Technique(patient factors)
- Awake intubation (topicalization IV
lido 1.5mg/kg) - Causes HTN ? can rupture fragile intracerebral
vessels (mainly premies) - awake intubation OK if
- Pt is Moribund in need of resuscitation
- Persistent vomiting
9Choice of Intubating Technique(patient factors)
- Asleep intubation
- IV induction
- Mask induction
10Blood Pressure Control
- Normal newborn SBP 60-70 mm/Hg
- Controlled hypotension 40-50 mm/Hg
- SBP lt 40 mm/Hg requires vigorous Rx
- Fluid (10ml/kg) bolus
- Oxygenation controlled ventilation
- Then analgesia
- titrated doses of ketamine (0.5 mg/kg increments)
- followed by opioids (fentanyl 2.5 µg/kg
increments) - BEWARE of postop respiratory depression
11Emergence
- ? Extubation at conclusion (depends)
- Reversal of Muscle Relaxant
- Edrophonium (1mg/kg) will achieve 90 of reversal
in 2min. Use Atropine 0.01-0.02 mg/kg (Enlon
Plus) Faster reversal fewer muscarinic
side-effect - Neostigmine (0.06mg/kg) will achieve 90 reversal
in 10min. Use Glyco (0.01mg/kg) or Atropine - If extubating
- Awake state is associated with control of airway
reflexes - Awake open eyes, grasp ETT (purposeful
movements), cry (cant be heard d/t ETT but can
be observed) - If partially anesthetized ? laryngospasm, apnea
12Surgeries in the First Week of Life
- Congenital Diaphragmatic Hernia (CDH)
- Omphalocele Gastroschisis
- Tracheoesophageal Fistula (TEF) (hrs-days to
diagnose) - Intestinal Obstruction (hr-days to diagnose)
- Meningomyelocele
13Confounding Factors
- Prematurity
- When associated with Resp Distress Syndrome may
worsen surgical outcome - Use of surfactant has increase of survivors
- Associated Congenital Anomalies
- Presence of one congenital anomaly increases
chances of ANOTHER congenital anomaly - TEF mortality associated with congenital heart
defect is far greater than mortality d/t Sx
correction of TEF - TEF (15-25 cardiac anomaly)
- CDH (25-30 cardiac anomaly)
14Maternal Cocaine Use in Pregnancy
- Cocaine reduces catecholamine reuptake
- Accumulation of catecholamines
- Circulatory negative effects on uterus, umbilical
blood vessels (AVA), fetal CV system - Premie birth, IU growth retardation, CV abn
- One report showed low CO SV 1st day of life but
return to normal 2nd day - CV abn
- Periph pulm stenosis, RV conduction delay, RVH
- EKG abn
- ST T wave changes
15Congenital Diaphragmatic Hernia(CHD)
- 14000 live births
- 40-50 mortality (severe lung underdev)
- 90 detected in 1st week are left sided
- Defect is more than a hernia in diaphragm
- Anesthetic techniques dictated by patient
condition - PAP should not exceed 30 cm/H2O
16Embriologic features of CDH
- 5th-10th wk the gut is herniated or extruded to
the extraembryonic coelom - 7th wk diaphragm develops ? separate thoracic
abd cavitity - 9th 10th wk developing gut returns to
peritoneal cavity - If diaphragm closure is delayed or incomplete or
if the gut returns earlier prevent normal diaph
closure ? CDH ? degrees of herniation of
intestinal contents into the chest - L side closes later than R side ? higher
incidence on L side (foramen of Bochdalek)
17CDH scenarios
- If CDH developed early ? lots of gut pressing on
chest ? compression of developing lung bud ? very
small, hypoplastic lung - Bil hypoplastic lungs ? no survival
- If CDH developed later ? normal lung compressed
by gut - Large range of in between
- Relatively normal pulm vascular bed with various
degrees of pulm HTN that may revert to normal - Severe pulm hypoplasia abn pulm vasculature
(usually die)
18CDH Clinical Presentations
- 1st min APGAR may be WNL (determined by
oxygenation of placenta) - S/S r/t degree of herniation interference with
pulm Fx (may be evident at first or take hrs to
dx) - Severe case ? fast dx ? scaphoid abdomen d/t
absence of intraabd contents - Breath sounds on affected side are reduced or
absent - CXR confirms Dx quick
- Supportive Measures
- ETT controlled ventilation (High PIP ? pneumo)
- Decompression of stomach
19Surgery CDH
- Delay Sx until pt is stable (24-48hr to 1wk)
- ECMO preop ? weaned from ECMO scheduled for Sx
- Other pts have Sx while on ECMO remained on
ECMO up to 30 days - CDH pts are surfactant-deficient (ECMO allows
surfactant system to mature) - When is best time for Sx?
- Wait until pulm vascular resistance is decreased
20Anesthesia CDH
- 2 factors to consider
- Pulm Fx
- Ability to close abdominal incision
- If normal lungs small hernia may consider
extubation _at_ end of Sx or shortly after - Most often, stay intubated for airway control
- After repair, return of gut to abd cavity may be
difficult (avoid N2O) - Lung should be re-expanded gently under DV
(PIPlt30mmHg). - Contralateral pneumo is possible if ( high PIP
needed (suspected if desaturation and/or
hemodynamic instability after pressure starts -
-
21Omphalocele
- Gut extrudes normally at 5th-10th week
- Gut normally returns to abdominal cavity at 10
weeks of intrauterine life - Failure of all or part of intestinal contents to
return ? omphalocele - Covered by membrane (amnion). Protects abd
contents from infection loss of extracellular
fluid. Sx can wait for several days - Umbilical cord at apex of sac
- Other congenital abnormalities frequently seen
- 20 have Congenital Heart Lesions
- Beckwith-Wiedemann Syndrome
- Omphalocele, Mental retardation, hypoglycemia,
congenital heart dz, large tongue
22Gastroschisis
- Develops later in fetal life, after gut has
returned to abdomen - Interruption of omphalomesenteric artery
- Dissolution of abdominal wall tissue at base of
umbilical cord - Umbilical cord found to one side of intestinal
contents - Gut herniates through defect
- Slight or complete
- No sac (infection loss of extracellular fluid)
need Sx within 12-24hrs - Other defects not frequent
- GI defects common with both Gastroschisis
Omphalocele - Intestinal atresia/stenosis
- Malrotation
23Delivery Room Management of Gastroschisis
- Controversy
- C-section advocates
- Prevent trauma to exposed gut
- Allows better coordination of team of specialists
- Vaginal delivery advocates
- Most pts with abd wall defects are born w/o
injury to bowel - Goal ? Protection of exposed bowel minimization
of fluid/temp loss - bagging pt (placing lower body in sterile,
clear plastic bag filled with warm saline
tightened to pts body
24Gastroschisis Periop Concerns
- Fluid loss (may need to administer large amounts
of full-strength balanced salt solutions) - Adequacy of peripheral circulation UO reflexes
appropriate fluid resuscitation - Infection
- Associated Congenital Anomalies
- Postop HTN Ventilation
25Gastroschisis Periop Concerns
- If defect is small ? primary closure
- Excellent skeletal muscle relaxation needed
- If defect is large ? difficult to return viscera
to peritoneal cavity d/t underdevelopment of abd
muscle peritoneum (no N2O!!) - A silo is used to contain/cover viscera q2-3
days the size of the silo is reduced (staged
repair) similar to squeezing a tube of toothpaste - Pt may feel some discomfort (ketamine 0.5-1mg/kg)
- Pt is usually not intubated at this time (allows
assessment of appropriate silo reduction w/o
impairing ventilation/circulation - Final stage is Sx to complete closure of
abdominal wall
26Postop Care of Gastroschisis
Omphalocele
- May need ETT for 3-7 days
- Postop HTN edema of extremities
- Increased abd pressure reduces circulation to
kidneys ? release of renin ? activation of
renin-angiotensin-aldosterone system ? HTN - Obstruction of venous circulation of lower body ?
edema of legs (large amounts of extracellular
fluid resuscitation needed)
27Tracheoesophageal Fistula(TEF)
- 1-3000 live births
- 50 have associated congenital
- anomalies
- Death d/t
- prematurity
- associated congenital heart defect (15-20)
- 85 fistula from distal trachea to esophagus
blind proximal esophageal pouch (85-90 are type
III-B) - 10 blind proximal esophageal pouch with no TEF
- Embryologic defect from imperfect division of
foregut into the anteriorly positioned larynx
trachea the posteriorly positioned esophagus
28Tracheoesophogeal Fistula
29TEF Clinical Presentation
- Inability of fetus to swallow amniotic fluid d/t
esophageal atresia ? polyhydramnios - If polyhydramnios seen in U/S ? attempt NG tube
after delivery (not routine in delivery room so
TEF may not be seen until pt is fed ? choking
cyanosis - Concerns Aspiration pneumonia Dehydration
- At times a G-tube is needed prior to repair of
TEF d/t high degree of reflux pneumonia - Actual Surgical repair consists of ligation of
fistula primary repair with approximation of 2
ends of esophagus (NG Tube helps surgeon as
landmark)
30TEF Anesthetic Considerations
- If G-tube is present ? open to air kept at head
of table to prevent kinking/obstruction - Intubation Technique (avoid excessive press
ventilation) - Awake
- Topicalization (2 lido spray 5mg/kg) of airway
Lido IV (1.5mg/kg) - Asleep (two techniques)
- Inhalation Induction followed by topical lido in
intubation keeping spontaneous ventilation - Inhalation or IV induction w/ intubation after
paralysis
31Tracheoesophogeal Fistula
- Essential airway techniques
- Avoid excessive positive pressure before
intubation - ETT tip between fistula and carina (perform
endobronchial intubation start to slowly pull
ETT back until BBSE again) - The ETT may go into the fistula by accident
during - Initial intubation
- Turning pt
- Surgical manipulation (surgeon can palpate tip of
ETT in fistula) - Be suspicious if increased difficulty in
ventilating pt, low O2 sats, low ETCO2 - A-line indicated
- Avoid post repair neck extension
32VATER syndrome
- Vertebral defects
- Anal atresia
- TEF
- Esophageal atresia
- Renal dysplasia
33Intestinal Obstruction(Upper GI obstruction)
- Seen within 24hrs ? feedings ? vomiting
- Fluid/electrolyte deficits (mostly Na)
- Aspiration (awake intubation may be needed)
- Anesthetic management tailored to
- Adequate relaxation
- Repair of defect
- Closure of abd
- GETA combined with Caudal
- May need postop ETT with PEEP
34Intestinal Obstruction(Lower GI obstruction)
- Seen b/w 2 to 7 days of age ? progressing
distension ? little or no stool is passed ?
vomiting ? fluid/electrolyte imbalance - Lots of fluid may be sequestered within the
intestinal tract (high Na) - Preop labs ? Na needs to be gt130mEq/L
- Preop UO ?1-2ml/kg/hr
- Imperforate anus should be Dx after birth
35Lower GI obstruction
- If minimal or no vomit ? RSI
- If mod-high vomit ? Awake intubation after
gastric decompression (even if an NG tube is in,
there is no guarantee that stomach is empty) - No N2O
- Think twice before electing to extubate
36Meningomyelocele
- 5 concerns
- Infection
- Fluids
- Position for tracheal intubation
- Presence of Arnold-Chiari malformation
- Hydrocephalus
37Meningomyelocele
- Infection Fluid
- Sac can break/leak d/t trauma, positioning,
delivery - Leakage of CSF (serum levels of Na K) can lead
to electrolyte problem. Replace with
full-strength balanced salt - If large meningomyelocele long Sx, additional
third space blood loss may result - Position for Intubation
- Place padding while pt is supine to avoid contact
of meningomyelocele with hard OR table surface
38Meningomyelocele
- Arnold-Chiari Malformation
- Caudal displacement of brain stem cerebellar
tonsils into cervical spinal canal - Associated with an obliteration of the normal
exit foramina of 4th ventricle - gt90 cases ? hydrocephalus ? shunt Sx
- Hydrocephalus is usually not present during
Meningomyelocele repair but later on in postop - Unusual breathing or BP patterns ? inc ICP?? ?May
develop hoarseness feeding difficulties - Pts with Arnold-Chiari Malformation,
hydrocephalus increased ICP ? bilateral vocal
cord paralysis (cause?)
39Hydrocephalus
- May occur after closure of meningomyelocele d/t
Arnold-Chiari Malf - Cranial sutures of neonates are open
- Increases in ICP are minimized/blunted
- Pt with hydrocephalus eventually has increase in
head size, inc ICP ? lethargy, vomiting,
cardioresp problems
40HydrocephalusAnesthetic Approach
- Intubation technique depends on condition
- Major issue airway protection control of ICP
- Awake intubation
- Laryngoscopy, crying, struggling, straining ?
increase ICP - Asleep intubation may be preferred
- RSI (4-5mg/kg Pentothal or 2-3mg/kg Propofol
Sux) - Hyperventilation Barbiturate will control ICP
- VAA, N2O, opioids for maintenance
- Keep intubated with PEEP postop if preop apnea
bradycardia was seen as result of inc ICP
41Surgical Procedures in the First Month of Life
- E-lap for Necrotizing Enterocolitis (see Pedi
Lecture by G. Hogan) - Pyloric Stenosis (See Pedi Lecture by G.
Hogan) - Inguinal Hernia repair
- PDA ligation
- Placement of CVP
42Inguinal Hernia Repair(IHR)
- Statistics
- Of 100 infants lt2 month old who needed IHR
- 30 were premies, 42 h/o RDS, 16 were on
Ventilators, 19 h/o Cong Heart dz - 31 had incarcerated hernias, 9 had intestinal
obstruction, 2 had gonadal infarction - Data precludes waiting until premie reaches 6mo
or 1yr before electivesx
43Inguinal Hernia RepairAnesthetic Techniques
- GA (with or w/o local as adjunct)
- Regional (combined with GA)
- Ilioinguinal-iliohypogastric nerve block
- 0.25 Bupivacaine 3mg/kg with epi affords
excellent postop analgesia w/o need for opioids
44Inguinal Hernia RepairPost Op Apnea in Premies
- Premies can develop apnea postop ? prolonged
associated with bradycardia - Respond well to O2 Tx stimulation
- Rarely reintubation is needed postop but
respiratory status must be closely monitored - Consensus today
- Premies younger than 50wks postconceptual age
should stay overnight
45Ligation of PDA
- Number of small premies is increasing ? number of
pts with PDAs with heart failure resp failure
is ALSO increasing - Prostaglandin relaxes smooth muscle of PDA
- Indomethacin (Prostaglandin Synthetase inhibitor)
is used to close the PDA - Indomethacin is usually unsuccessful in Tx of
small premies because of lack of muscle within
PDA - Maximal medical management with fluid restriction
diuretics - Usually stay intubated postop
46Placement of Central Venous
Catheter
- Monitoring lytes for Hyperal
- IV meds
- 3 major concerns
- Airway management (ETT)
- Pneumothorax
- Bleeding (hemothorax, hypovolemia)
47References
- Barash 1080-1084, 1098-1112
- NZ 1148-1164
- Cote 5-24, 353-395