This document outlines anesthetic considerations for various pediatric neurosurgical conditions including myelomeningocele, hydrocephalus, and cleft lip/palate. It discusses the types and features of spina bifida, considerations for myelomeningocele repair including positioning and airway management. It also covers facts about cerebrospinal fluid physiology and production, the pathophysiology and management of hydrocephalus, and highlights challenges such as maintaining cerebral perfusion and preventing increased intracranial pressure during shunt procedures.

1. MMC, HCP, CL&CP
Tamrat kelelegn (addis ababa university)

2. Outline
12/28/2019BY TAMRAT.K2
 Types Spina bifida and features
 Anesthetic consideration for Myelomeningocele
 Facts and Physiology of CSF
 Anesthetic consideration for hydrocephalus
 Anesthetic consideration for cleft lip and cleft
palate

3. Spina Bifida “ split spine ”
 Defined as midline defects involving failure of the
bony spine to close.
Spina bifida occulta - defect not visible externally.
 Occurs most often in lumbosacral area.
 Not apparent unless there are gait disturbances,
foot deformities, sphincter dysfunction or other
neuromuscular manifestations.
 Many people with occulta will never have any
deficits and may not know they have it.
12/28/2019BY TAMRAT.K3

4. Spina Bifida cystica - visible defect with external
saclike protrusion.
A. meningocele- encases meninges and spinal
fluid, but no neurological deficits.
B. Meningomyelocele -contains meninges, spinal
fluid, and nerves.
 Neuromotor deficits depend on anatomic level of
protrusion and nerves involved.
 clinically most significant is myelomeningocele
(MMC; open Spina bifida)
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5. 12/28/2019BY TAMRAT.K5

6. Myelomeningocele
 Myelomeningocele is the most common
congenital primary neural tube defect.
 Women who take 400 mcg of folic acid every day
reduce the risk by up to 70%.
 occurs in approximately 0.5 to 1 of every
1,000 live births.
 It results from failure of neural tube closure
during the fourth week of gestation.
12/28/2019BY TAMRAT.K6

7. Cont. …..
Dx
 prenatal ultrasound.
 Elevated maternal serum AFP(α fetoprotein)
detects 50% to 90% of open neural tube defects
but has a false-positive rate of 5%.
 Amniotic fluid AFP is more reliable and
typically used for confirmation after elevated
serum levels.
 cystic mass on the back containing a neural
placode, arachnoid, dura, nerve tissue and
roots, and cerebrospinal fluid.
12/28/2019BY TAMRAT.K7

8.  The lesion most commonly occurs in the
lumbosacral(85%) or sacral region, although it can
extend to the thoracic region.
 The bony canal is also malformed, leading to
multiple orthopedic problems as the child matures.
 have an associated anomaly of the brainstem known
as the Arnold–Chiari II (Chiari II) malformation.
 The Chiari II malformation is characterized by
caudal displacement of the cerebellar vermis
through the foramen magnum, caudal
displacement of the medulla oblongata and the
cervical spine, kinking of the medulla, and
obliteration of the cisterna magna.
12/28/2019BY TAMRAT.K8

9.  Post MMC Hydrocephalus requiring shunting
approximately 80% to 90% of infants with
myelomeningocele.
 And 20% of patients have a brainstem
dysfunction the mortality rate among those
symptomatic patients is high.
 Complications of brainstem dysfunction include
stridor, apnea and bradycardia, aspiration
pneumonia, sleep-disordered breathing patterns,
vocal cord paralysis, lack of coordination, and
spasticity.
 If the symptoms are not improved by shunting,
posterior fossa decompression is necessary.
12/28/2019BY TAMRAT.K9

10.  The infant with a myelomeningocele is usually
operated on within the first 24 to 48 hours of life.
 This reduces the risk for development of ventriculitis
or progressive neurologic deficits.
 Most centers close the defect and place a shunt
at the same time.
 However, some centers may delay placement of
a shunt until the infant shows symptoms of
hydrocephalus.
 There is ongoing work(studies) to determine the
benefits of intrauterine repair of
myelomeningocele, hopefully with the benefits of
decreased development of a Chiari II
malformation, decreased hydrocephalus, and
increased lower limb function.
12/28/2019BY TAMRAT.K10

11. Preoperative Care
 focuses on the prevention of infection,
maintenance of ECF volume, avoidance of
hypothermia, and assessment for other congenital
anomalies.
 The exposed neural placode is susceptible to
trauma, leakage, and infection.
 The infant is usually placed in the prone position,
and the placode is covered with warm saline-
soaked gauze to prevent drying.
 Because of the high risk of infection, antibiotic
therapy is initiated in the preoperative period.
 Rupture of the cyst on the back can lead to
ongoing cerebrospinal fluid leakage.
12/28/2019BY TAMRAT.K11

12.  This fluid is replaced with a full strength,
balanced salt solution(NS).
 The infant is also assessed for any
potentially life-threatening congenital anomalies.
12/28/2019BY TAMRAT.K12

13. Perioperative Care
 The high prevalence of clinical latex allergy and
latex sensitization in children with
myelomeningocele
 Positioning is critical in the infant with
myelomeningocele.
 For induction of anesthesia, the infant may
be placed supine with the defect resting in a
“doughnut” to minimize trauma.
12/28/2019BY TAMRAT.K13

14.  Rolls are positioned to ensure the abdomen and
chest are free
 In most instances, the infant has an
intravenous line placed before surgery and an
intravenous induction is performed.(IV vs
inhal?)
 Succinylcholine may be used to facilitate
intubation
 increased intracranial pressure is rarely
present before closure of the defect,
 Inhalational induction is an alternative in the
infant with difficult intravenous access. 12/28/2019BY TAMRAT.K14

15.  The anesthetic management of these newborns
is rarely complicated unless there are other
congenital anomalies that warrant special
attention.
 Regional anesthesia has been reported as a safe
adjunct or alternative to general anesthesia in the
neonate with myelomeningocele.
 Studies or One small series has been published in
which tetracaine spinals were used as the anesthetic
for 14 infants undergoing repair of
myelomeningocele. In this series, there was no
evidence of anesthetic-induced neurologic damage.
Of note, 2 of the 14 infants had a postoperative
respiratory event (1 transient apnea/bradycardia
and 1 brief desaturation with bradycardia). Both
of these infants had received intraoperative
midazolam for sedation. 12/28/2019BY TAMRAT.K15

16. Post operative Care
 Infants must be monitored closely in the
postoperative period.
 Respiratory complications, including stridor,
apnea and bradycardia, cyanosis, and
respiratory arrest (infant with Arnold–Chiari II
malformation )
 post MMC signs of hydrocephalus, including
lethargy, vomiting, seizures, apnea and
bradycardia, or cardiovascular instability.
 majority of these patients will eventually
require a shunt(1/3).
12/28/2019BY TAMRAT.K16

17. Facts and Physiology of CSF
12/28/2019BY TAMRAT.K17

18. Facts and Physiology
 The majority of CSF is produced by the choroid
plexus within the brain through a metabolically
active process (i.e. requires ATP) whereby
sodium is pumped into the subarachnoid space,
and water follows from the blood vessels.
 Choroid plexus is primarily located in the lateral
ventricles (temporal horn roofs, and floors of
bodies), posterior 3rd ventricle roof, and caudal 4th
ventricle roof.
12/28/2019BY TAMRAT.K18

19. Facts and Physiology
 The average adult brain produces between 450
and 600 cc’s of CSF every day.
 Normally, production = resorption.
 At any given moment, there is only ~150 cc’s of
CSF present in the average adult; of this, only
~25 cc’s is within the brain ventricles!
 So, the CSF volume turns over three to four times
every day, with only a very small fraction of the CSF
being in the ventricles at any given time, even
though the majority of it is produced there!
12/28/2019BY TAMRAT.K19

20. Important concept to build on
 The CSF production/ resorption system exists in a
delicate balance under normal conditions.
 The normal range of ICP in neonates and infants
is 0-6 mm Hg/2-6 mmHg.
12/28/2019BY TAMRAT.K20

21. The CSF pathway
 From the lateral ventricle (remember, there are
two…one on each side), CSF travels through the
foramen of Monro into the 3rd ventricle (midline),
then passes through the Cerebral Aqueduct [of
Sylvius] into the 4th ventricle. It then exits the 4th
ventricle through either of two Foramina of
Luschka (“L” is for Lateral/Luschka) or the single
Foramen of Magendie (“M” is for
Midline/Magendie).
12/28/2019BY TAMRAT.K21

22. CSF pathway (cont’d)
 After exiting the 4th ventricle, the CSF flows
through the subarachnoid space over and around
the brain and spinal cord, and is eventually
reabsorbed into the venous (blood) system
through numerous arachnoid granulations along
the dural venous sinuses (especially the superior
sagittal sinus).
12/28/2019BY TAMRAT.K22

23. CSF pathway (cont’d)
 Arachnoid granulations contain arachnoid villi,
which function as pressure-dependent one-way
valves that open when the ICP is ~3 to 5 cm H20
greater than dural venous sinus pressure.
 Remember – CSF production is a metabolically
active process which uses ATP, whereas CSF
resorption is a passive process that is driven by
the pressure gradient between the intracranial
space (ICP) and the venous system (~CVP).
12/28/2019BY TAMRAT.K23

24. Hydrocephalus
• A syndrome, or sign, resulting from disturbances in
the dynamics of cerebrospinal fluid (CSF).
Two major distinctions:
 Communicating Hydrocephalus (CoH)
 Also known as “non-obstructive” hydrocephalus
 Comm. Hydrocephalus CSF production > resorption
 As a result, the ventricular system dilates uniformly, and ICP
rises.
ethology COH
 Infection (incidence after bacterial meningitis can
approach 30%)
 Subarachnoid Hemorrhage (blood and blood
breakdown products cause scarring of arachnoid
granulations)
 Post-operative
 Head trauma 12/28/2019BY TAMRAT.K24

25. Non-communicating Hydrocephalus (NCH)
 Most cases of non-communicating (obstructive)
hydrocephalus are a result of developmental
malformations.
 Also known as “obstructive” hydrocephalus
 ANY physical obstruction to the normal flow of CSF before it
leaves the ventricles.
 NCH have Many, many causes:
 Aqueductal stenosis
 Tumors/Cancers/Masses
 Cysts
 Infection
 Hemorrhage/hematoma
 Congenital malformations/conditions
12/28/2019BY TAMRAT.K25

26. Clinical manifestations
 Head grows at alarming rate with hydrocephalus.
 First signs- bulging of fontanels without head
enlargement.
 Tense, bulging, non-pulsatile anterior fontanel
 Dilated scalp veins, esp. when crying
 Thin skull bones with separated sutures (cracked
pot sounds on percussion)
 Protruding forehead or bossing.
12/28/2019BY TAMRAT.K26

27.  Depressed eyes or setting-sun eyes (eyes rotating or
downward with sclera visible above pupil)
 Pupils sluggish with unequal response to light
 Irritability, lethargy, feeds poorly, changes in LOC,
arching of back (opisthotonos), lower extremity
spasticity.
 May cry when picked up or rocked; quiets when
allowed to lay still.
 Swallowing difficulties, stridor, apnea, aspiration,
respiratory difficulties and arm weakness may indicate
brain stem compression.
 If hydrocephalus progresses, difficulty sucking and
feeding, and a high-pitched shrill cry results. (lower
brain stem dysfunction) 12/28/2019BY TAMRAT.K27

28.  Emesis, somnolence, seizures, and
cardiopulmonary distress follows and
hydrocephalus progresses.
 Severely affected infants may not survive
neonatal period.
12/28/2019BY TAMRAT.K28

29. Diagnostic Evaluation
 Antenatal- fetal ultrasound as early as 14 weeks
 Infancy- based on head circumference crosses
one or more grid lines on the infant growth chart
within a 4 week period and there are progressive
neuro signs.
 CT and MRI to localize site of obstruction; reveal
large ventricles
12/28/2019BY TAMRAT.K29

30. Therapeutic management
Goals:
 Relieve hydrocephaly
 Treat complications
 USUALLY SURGICAL!
12/28/2019BY TAMRAT.K30

31. Surgical Treatment
 Therapy of choice!
 Direct removal of source of obstruction
(neoplasm, cyst, or hematoma)
 Most require shunt procedure to drain CSF from
ventricles to extracranial area; usually
peritoneum(VP shunt), or right atrium (VA shunt)
for absorption.
12/28/2019BY TAMRAT.K31

32. Anesthetic management
 Ventriculo-peritoneal (VP) shunt insertion can be
performed as an emergency or an elective procedure.
 Anesthesia management for VP shunt insertion
provides specific challenges.
a. Airway management in small patients with large
heads because of hydrocephalus
b. Maintaining adequate cerebral perfusion and
preventing increase in ICP during the surgery,
especially during periods of stimulation such as
intubation and tunneling of shunt
c. Selection of anaesthetic agents which prevents
increases in ICP while also allowing rapid
emergence.
 Awake tracheal intubation, crying, struggling, and
straining can increase intracranial pressure.
12/28/2019BY TAMRAT.K32

33. 12/28/2019BY TAMRAT.K33
Pre-anaesthetic check-up
 Usual components of PAC
 Comorbidities of the patient and clinical
assessment of the evidence of ICP elevation.

34. 12/28/2019BY TAMRAT.K34
Induction of anaesthesia
 Standard monitoring, invasive monitoring is not
normally required, unless there is comorbidities.
 Paediatric patients without an intravenous access can
be induced using inhalational
 Antibiotic prophylaxis to reduce the incidence of
wound infection.
 Except for ketamine, all intravenous induction agents
can be used.
 Succinylcholine can be used for muscle relaxation if
the risk of aspiration outweighs the problems of
transient increases in ICP.
 Otherwise non depolarizing Neuromuscular blockers

35. 12/28/2019BY TAMRAT.K35
 Intubation can prove to be challenging in patients
with increased head circumference.
Positioning
 supine with the head rotated to the opposite
side.
 Adequate padding of the eyes
 aware of possible endotracheal tube migration
while the patient is positioned for surgery

36. 12/28/2019BY TAMRAT.K36
Maintenance of anaesthesia
 A balanced technique of anaesthesia is usually
advised
 Involving NDMRs, inhalational agents (up to 1.5 MAC)
and opioids.
 Nitrous oxide increases cerebral blood flow and is
therefore not recommended
 An increased depth of anaesthesia or administration
of short acting opioids is advised during initial incision
and tunnelling for distal catheter to attenuate increase
in heart rate and ICP.
 Prevention of hypothermia is important (mild to
moderate advantageous)

37. Post operative consideration
 Infants may remain intubated if they were
experiencing periods of apnea or bradycardia
before surgery because of the intracranial
abnormalities.
 If not, the trachea can be extubated as soon
as the protective reflexes of the airway have
recovered.
 pain mgt Local anaesthetic infiltration can be
employed for post operative pain control along
with paracetamol, NSAIDS and opioids (under
observation). 12/28/2019BY TAMRAT.K37

38. Major Complications
 Shunt infection is most serious complication
 Mechanical difficulties
kinking, plugging, migration of tubing.
 Look for signs of increased ICP; fever,
inflammation and abdominal pain.
Article
12/28/2019BY TAMRAT.K38

39. Anaesthesia for Cleft Lip and Palate
Surgery
12/28/2019BY TAMRAT.K39

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42.  Cleft lip and palate are the commonest craniofacial
abnormalities.
 A cleft lip, with or without a cleft palate, occurs in 1 in
600 live births.
 A cleft palate alone, is a separate entity and occurs in
1 in 2000 live births.
 Embryologically, clefts arise because of failure of
fusion or breakdown of fusion between the nasal and
maxillary processes and the palatine shelves at
around 8 weeks of life.
 If its not repaired children suffer from facial
disfigurement and potentially social isolation, feeding
problems and abnormal speech. 12/28/2019BY TAMRAT.K42

43. Surgical Timing
 Cleft lip : 1 to 5 months
 Cleft palate: 6-8 months and older
Benefits of Delaying Surgery
 Decrease in anesthetic risk
 Diagnosis of other anomalies
 Better repair of lip and nose
 Allows more time for parents to make mental
adjustments to child with deformity
12/28/2019BY TAMRAT.K43

44. Preoperative evaluation
In addition to the standard preoperative history and
examination special care needs to be taken in
assessing the following:
 Associated congenital abnormalities.
 Congenital heart disease
 Chronic rhinorhoea
 Chronic airway obstruction/sleep apnoea.
 Right ventricular hypertrophy and corpulmonale
 Anticipated difficult intubation
 Nutrition/hydration.
 Need for premedication.
12/28/2019BY TAMRAT.K44

45.  Cleft lip and palate is associated with about 150
different syndromes
 The combination of a cleft palate, micrognathia
and upper airway obstruction constitutes the
Pierre-Robin Syndrome.
 Other common syndromes are the Goldenhar
Syndrome and Treacher Collins Syndrome
12/28/2019BY TAMRAT.K45

46. 12/28/2019BY TAMRAT.K46

47.  Congenital heart disease occurs in 5 - 10%
 Chronic rhinorhoea common in children
presenting cleft palate closure and is due to reflux
into the nose during feeds. It needs to be
distinguished from active infection that could
require postponement of the surgery.
 Parents of infants with cleft palates tell history of
snoring or sleep apnea.
 Right ventricular hypertrophy and corpulmonale
may result from recurrent hypoxia
 They are very sensitive to any respiratory
depressant effects of anaesthetic agents,
benzodiazepines opioid analgesics. 12/28/2019BY TAMRAT.K47

48.  A difficult intubation is especially common in
with either retrognathia (receding lower jaw) or
bilateral clefts.
 Nutrition/hydration
 Need for premedication.
 Sedative premedication is not indicated
 Atropine may be prescribed to dry oral
secretions and block vagal reflexes.
12/28/2019BY TAMRAT.K48

49. Intraoperative Management
 If available RAE/armored ET tubes are best
 Induction of anaesthesia is most safely performed
by inhalational anaesthesia
 Endotracheal intubation may be difficult,
especially in children with a craniofacial
syndrome
 variety of techniques such as blind nasal
intubation, fibreoptic intubation, the use of
bougies or retrograde techniques may need to be
employed.
12/28/2019BY TAMRAT.K49

50. Studies
 Gunawardana and Arteau-Gauthier et al. studied risk
factors for difficult laryngoscopy in children with CP. These
children did not have any identified syndrome. 5–7% of
patients in these studies had difficult laryngoscopy, a
higher incidence than in other pediatric patients.
 Large or bilateral clefts, micrognathia and age less than 6
months were associated with increased incidence of
difficult laryngoscopy.
 Large and bilateral clefts can be difficult because the blade
of the laryngoscope can fall into the cleft. Should this
occur, one can pack the cleft with gauze to improve the
laryngoscopy. No patients in these studies were
associated with difficult mask ventilation. Since mask
ventilation is not difficult in most of these patients, an
inhaled induction with volatile anesthetic with control of
ventilation is appropriate in most of these patients in
experienced hands.
12/28/2019BY TAMRAT.K50

51.  The surgeon or anesthetist will insert an oral pack
 A head ring and a roll under the shoulders is
frequently used.
 Problems with the endotracheal tube are
common.
 Check after position
12/28/2019BY TAMRAT.K51

52.  Maintenance of anaesthesia with an inhalational
agent can be with spontaneous ventilation or
controlled ventilation.
 A spontaneous breathing technique with
halothane. (adva?)
 Controlled ventilation with muscle paralysis.
 Infiltration of local anaesthetic and adrenaline into
the surgical field.
12/28/2019BY TAMRAT.K52

53.  paracetamol 20mg/kg orally as premedication
or rectal paracetamol post induction (40mg/kg)
 Morphine sulphate 0.1-0.2mg/kg intravenously
is commonly used and provides good early
postoperative analgesia.
 NSAIDS, although very effective analgesics.
 cleft palates will occasionally require blood
transfusion.
 Appropriate intravenous fluids should be
given.
 Attention to temperature control
12/28/2019BY TAMRAT.K53

54. Extubation
 Acute airway obstruction is a very real risk at the
end of the procedure following extubation.
 Remove the throat packs and dry surgical field.
 Suctioning should be kept to a minimum to
avoid disrupting the surgical repair.
 Oropharyngeal airways are best avoided, if
possible.
 Extubation should be undertaken only after the
return of consciousness with protective reflexes
intact.
 A tongue stitch will often be placed in patients
with preoperative airway obstruction. 12/28/2019BY TAMRAT.K54

55. Postoperative Management
 Close observation for blood loss or airway
obstruction at PACU
 Supplemental oxygen
 Additional analgesia
 Infraorbital Nerve Block
12/28/2019BY TAMRAT.K55

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References
 Barash Clinical Anesthesia 8th ed.
 Update in Anaesthesia, anesthesia for cleft lip
and cleft palate.
 Essentials of Pediatric Neuroanesthesia.

57. 12/28/2019BY TAMRAT.K57
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