Anesthesia for Common Pediatric Procedures Flashcards
What is myelodysplasia?
spina bifida
failure of the neural tube to close resulting in herniation of the spinal cord and meninges through a defecy
Meningocele
only contains meninges
Myelomeningocele
contains meninges and neural elements
Hydrocephalus
condition in which excess cerebrospinal fluid builds up within the fluid containing cavities or ventricles of the brain
What is the most common CNS defect that occurs in the first month of gestation?
myelodysplasia
What are risk factors for myelodysplasia?
folate deficiency
chromosomal abnormalities
Where do myelodysplasia commonly occur?
lumbosacral region
What is normal present with myelodysplasia?
hydrocephalus and paralysis may occur below the leison
Why is myelodysplasia urgent?
surgery within 24-28 hours due to risk of infection or worsening cord function
Preoperative considerations for myelodysplasia repair
assess level of leison and degree of deficit
review systems and rule out congenital abnormalities
CBC and TS
Intraoperative considerations for myelodysplasia repair
routine monitors, may use intraoperative monitoring (avoid muscle relaxation if MEPs are utilized)
positioning
induce with inhalation or IV
potential BL if its a large defect
prone to hypothermia
latex free
Post-operative considerations for myelodysplasia
goal is to extubate
assess the need for postoperativel apnea monitoring
How is hydrocephalus caused?
by a congenital defect (arnold-chiari aqueduct stenosis) or by acquired disease (trauma, infection, tumor)
What is a ventriculoscopy?
use of fiber optic scope through cranial burr holes to visualize lateral, third adn occasional fourth ventricle
alternatively shunts may be positioned under the ultrasound guidance
What is a Vetriculo-peritoneal shunt?
lateral ventricle to peritoneum
most common and allows for growth
What is an ventriculo-atrial shunt?
lateral ventricle to right atrium
What is an endoscopic third ventriculostomy (ETV)
burr hole created in the floow of the 3rd ventricle allowign CSF to flow directly into the basal cisterns
Preoperative considerations for CSF shunts
assess baseline neurological status and ICP
avoid pre-meds if ICP is increased
assess for vomitting history and dehydration
routine HP
if child had repeated shunt revisions
review previous anesthesia history
IV 1-2
Induction considerations for CSF shunts
standard monitors
propofol, fentanyl, roc
isoflurane or sevoflurane
GETA
protect and pad eyes
antibiotics cefazolin 30mg/kg IV
Maintenance for VP shunt
hyperventilation is not wanted because it can make the cannulation of the ventricle more difficult
What do you need to be aware of with VA shunts?
be caution of air embolism/ PPV while the vein is open
Emergence for VP shunt
reversal of paralytic
anti-emetic
extubate
fully awake to permit for rapid neurological assessment
Where can the three fractures occur in the humerus?
Proximal of humerus
mid shaft of the humerus
distal of the humerus (near your elbow) [More complex injury and sometimes involves loos bone fragments
What is idiopathic scoliosis?
no definite cause
most common form >70% of the condition and mainly affects adolescent girls
What is neuromuscular scoliosis?
caused by conditions of muscle weakness or spasiticity (such as CP), muscular dystrophy, spinal cord injury
Which form of scoliosis is associated with more bleeding?
nueromuscular scoliosis
What is the most common elbow fracture in children?
supracondlylar fractures
results from falling on an outstretched hand and extended elbow
What are complications of a supracondlylar fracture?
compartment syndrome
nerve palsies
late deformities
Anesthesia considerations for upper arm fractures
supine with table turned 90 degrees
GETA (LMA vs ETT)
usually ETT b/c full stomach + RSI
30-60 minutes for pinning
30-90minutes for open reduction
timing of emergence if case or splint is placed after closing
When is surgical treatment recommended for scoliosis?
surgical treatment is recommended for patients whose curves are greater then 45 while still growing or continuing to progress >45 when growth stopped
What is the goal of surgical treatment?
prevent curve progression
obtain some curve correction
What does surgical treatment of posterior spinal instrumentation include?
metal implants that are attached to the spine, and then connected to a single rod or two rods
posterior vs anterior (may require one lung ventilation)
Anesthesia implications for posterior spine instrumentation
prone positioning
6+ hours
potential for significant blood loss
intraoperative neurological monitoring utilized when possible wake up test
step down or icu postoperatively
Pre-operative anesthesia implications for posterior spine
standard pediatric pre op evaluation
CBC coagulation BMP HCG in females
comorbidites
TC set up 2 units, cell saver
Nerve monitoring goals and paralytic use
prepare patient or family for puffy face from prone position
What is the cobb angle?
the degree of lateral curvature
- can impair respiratory function
What is the respiratory compliance of patients with scoliosis?
restrictive
decreased TLC and VC
At what VC is respiratory reserve adequate?
<70%
At what VC is respiratory reserve compromised and may require post operative ventilation?
<40%
What are patients with neuromuscular scoliosis more sensitive too?
require post-operative ventilation s/c to muscle weakness
Succinylcholine needs to be avoided in patients with
mucular dystrophies, motor neuron disease, intrinsic muscle disorders d/t risk of MH, hyperkalemia, and cardiac arrest
Describe the case set up for spinal fusions
cell saver, fluid warmer, blood tubing
aline PIVx2 (CVL if difficult access)
prepare prone position with superman arms
bilateral bite blocks
posterior EKG placement, prone pillow, spinal underbody bair hugger
standard airway, induction meds, BIS, cerebral ox, emergency meds and OG
ensure room temperature is increased into OR
What drugs are compatible with MEPs, SSEPs, and EMG monitoring?
dexmedetomidine, opioids
low dose of dex does not affect MEPS/SSEPs, but may in high doses
What should dex gtt be kept below?
0.03mcg/kg/hr
What is avoided for MEP SSEP EMG
nitrous and inhalation agents
What enhances SSEPS and MEPs ?
ketamine enhances the amplitude
given as a bolus or discontinue as an infusion
IOM team should be informed
What drug at high doses can increase latency and decrease amplitude of EP?
propofol
keep doses <130-150mcg/kg/min
What are complications of spinal cord surgery?
spinal cord ischemia
massive blood loss
embolism
accidental extubation
corneal abrasion
visual loss
neurological sequel with loss SSEPs or MEPs
Postoperative Anesthesia care for spinals
plan for extubation if possible
chest xray at end of procedure with patient supine on the inpatient bed
(ensure surgeon is happy with xray)
pain score 7-9-> hydromorphone PCA
ICU or step down
LOS 2-6 days
What is a nissen?
laparoscopic nissen fundoplication is minimally invasive procedure which is done to restore the function of the lower esophageal sphincter by wrapping the stomach around the esophagus
What is infantile hypertrophic pyloric stenosis?
thickening or swelling of the pylorus- the muscle between the stomach and the intestines that causes severe and forceful vomiting in the first few months of life
enlargement of the pylorus cuases a narrowing (stenosis) of the opening from the stomach to the instestines, which blocks the stomach from contents from moving into the intestine
Anesthesia implications for Nissen
gastric reflex management has failed
involves mobilizing the muscles around the esophagus at the level of lower esophageal spinchter
GA ETT
often laproscopic
not associated with large blood loss, fluid shifts or pain
positioning of bougie within the esophagus and insufflation via the gastric tube to ensure no leaks at the anastomosis
What is hypertrophic pyloric stenosis?
palpable obstructive lesion “olive shaped” enlargement of pylorus
usually diagnoses between 2-12 week
How does hypertrophic pyloric stenosis present?
post prandial projectile emesis, palpable pylorus, visible peristalic waves
persistent volmiting depletes sodium, potassium, chloride and hydrogen ions causing hypochloremic metabolic alkalosis
– kidneys attempt to compensate by excreting sodium bicarbonate
hyponatremia/dehydration worsen and kidneys attempt to conserve sodium at the expense of hydrogen
What is the surgical correction for a hypertrophic pyloric stenosis?
plyoromyotomy
“semi-elective” urgent, but must be medically managed first
(Dehydration, electrolytes, acid base)
What should be avoided in metabolic alkalosis?
LR
because lactate will metabolize to bicarbonate
Anesthesia implications for pyloric stenosis
prior to induction must suction stomach with OG
high aspiration risk
RSI with cricoid pressure
pre-oxygenate-> prop-> succinycholine/roc
cuffed ETT
quick procedure
extubate awake
What is a congenital diaphragmatic hernia? Early vs Late?
anatomic defects permit intrusion of abdominal contents into thoracic cavity
Early: abdominal mass inhibits normal cardiopulmonary growth
severity of lung hypoplasia (associated with morbidity and mortality- negatively correlates with gestational age at the time the hernia occurs)
late: occurs near or even after delivery; are associated with mature, well developed lungs and minimal problems with ventilation
What type of CDH is more likely to have concurrent birth defects and chromosomal abnormalities?
bochdalek-type hernia
95%
what are the hallmark signs of CDH?
hypoxia, scaphoid abdomen, evidence of bowel in the thorax
Why is CDH potentially lethal?
due to pulmonary HTN, pulmonary dysplasia, associated with cardiac or congenital defects
What are three major life-threatening changes in CDH to the infant?
hypoplastic lungs
intrapulmonary shunting and inadequate gas exchange
decreased total cross sectional area results in pulmonary arteriole hypertension
What does surgery for CDH cause?
surgery transiently worsens pulmonary HTN and may cause persistent fetal circulation (fetal circulation repoens PDDA and shunts blood which results in bypassing of the lungs)
What do CDH outcomes rely on?
function of the underlying pulmonary hypoplasia and pulmonary hypertension
Anesthesia management foro CDH repair
initial management includes definitive airway control and optimizaiton of oxygenation and ventilation
avoid mask ventilation to limit gastric insufflation (placement of NG and gastric decompression)
supine or lateral
pre and post ductal monitoring (provides an early warning sign of R to L shunting (pulm HTN)
reactive pulmonary vasculature (avoid increases in pulmonary vasculature resistance)
piv x2 cvl aline serial abgs
ebl 5-10ml/kg
paralysis, narotics, limited VA
limit inspired O2, avoid nitrous
supportive care during transport
What are conditions that increase pulmonary vasculature resistance?
hypoxemia
acidosis
hypotension
How has CDH treatment improved in recent years?
strategy of delaying surgery to ensure stabilization of the transitional circulation adopting a lung protective, or gentle ventilatory strategy to use small tidal volumes and low PEEP
higher PCO2 (permissive hypercapnea)
What is inhaled nitric oxide?
specific pulmonary vasodilator (avoiding systemic hypotension)
used for refractory pulmonary hypertension to decrease R to L shunting and improve oxygenation
short acting, must be delivered through a special apparatus
What is ECMO
temporizing measure permitting lungs to rest and mature while providing an appropriate gas exchange through membrane oxygenators
multiple inclusion and exclusion criteria (IVH contraindication)
VV (venovenous) or venoarterial (VA) location of inflow and outflow catheters
VV- double lumen resides in the internal jugular vein
VA is two catheters one in the jugular and other in the carotid artery
Why is sedation important in CDH?
to limit the catecholamine response with may increase pulmonary vasculature resistance
How should severe cardiovascular compromise be treated in CDH?
volume support and inotropic support
What is a circumcision?
removal of the foreskin form the human penis
the most common procedure
foreskin opened adhesions are removed and foreskin is separated from the glans
What is hypospadias?
condition in which the opening of the urethra is on the underside of the penis instead of at the tip
location of the opening can vary and can be anywhere from the underneath the tip of the penis (more common) to the base of the penis (less common)
What are indications for a circumcision?
phimosis, recurrent balanitis, parental preference
approximately 1 hour
most common complication is bleeding
Anesthesia implications for hypospadias
ga lma or ett
1-4 hours
regional is controversial (concern for venous pooling and poor outcomes
