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Pediatric Anesthesia for the Occasional Pediatric Anesthetist
Kimberly Westra CRNA, DNP, MSN, MBA (c)
Pediatric Anesthesia
● Children are not little adults
● Reduced frequency of pediatric cases results in exposure to pediatric cases, deskilling, reduced pediatric crisis management scenarios
Pediatric Pearls● Physiological &
anatomical variations require a availability of size appropriate equipment for Neonate to School Aged Child
● Invasive lines, regional procedures, airway devices are size specific
Pediatric Anesthesia
● Teams versus Generalist approach to Pediatrics
● Resources available ● Size appropriate
equipment color coded ● Monitors ● Airway ● Lines
Pediatric Anesthesia
● Large Heads ● Large Tongues ● Narrow Nasal
Passages ● Obligate Nose
Breathers till 5 months ● Position Head with
Support to align airway axis
Pediatric Airway & Obstruction Issues
Pediatric Airway & Overextension
Pediatric Airway Ideal Positions
Pediatric Airway
● Anterior Airway ● Glottis at C-4 and
cephalad ● Glottis U shaped &
long ● Trachea short ● Cricoid narrowest up
until about age 10 ● Glottic Abnormalities
Pediatric Respiratory ● Less alveoli & smaller
in parenchymal size ● Lung compliance
decreased ● Chest wall compliance
increased with cartilaginous rib cage
● Diaphragm easily fatigued
● Less type 1 muscles
Pediatric Respiratory
● Low Oxygen Reserves ● Underdeveloped
respiratory drive centers thus hypoxic & hypercarbia drives less effective
● Increase Oxygen consumption 7mg/kg/min
Pediatric Airway
● Pousielles Law for pediatric airways
● Resistance to airflow exponentially increased
● Mainstem risk ● Cuffed ETT vs Non
cuffed ETT
Pediatric Cardiac
● Fixed Stroke Volume ● Immature Sympathetic
& Baroreceptor response
● May see limited Tachycardia response to hypovolemia & hypotension
● Cardiac Output dependent upon HR
Pediatric Vital Sign Ranges
Pediatric Renal
● Decreased glomerular filtration rate
● Decrease creatinine clearance
● Decrease exertion of sodium, glucose, creatinine
● Decrease Bicarbonate Reabsorption
Pediatric RenalDecreased ability to regulate osmolarity! Close attention to fluid management Use of micro drip IV tubing versus drip chamber Use of stop cocks for easy flushing Access to close port on IV catheter
Pediatric Metabolic
● Low Glycogen Stores especially neonate & infants*
● Hypoglycemia: ● Neonates 30mg/dl ● Infant 40mg/dl ● Higher risk with Premies
and/or Hyperalimentation
Pediatric Metabolic● IV Fluids Neonate &
Infants: ● D5LR ● D5 ½ NSS ● D5 ¼ NSS ● Children: LR as
appropriate length/type of procedure
Pediatric Thermoregulation
● Risk of Hypothermia increased due to:
● Lack of Shivering under 1 yr.
● High body surface area to body weight
● Thin skin ● Low Fat content
Thermoregulation● Use Brown Fat for
thermogenesis ● Higher risk of
iatrogenic hypo/hyperthermia
● Must “prep room” with increasing temp in advance
● Use Active warming devices
Pediatric Pharmacology● Protein Binding
decreased ● Hepatic
Biotransformation reduced/impaired
● Neuromuscular junction immature
● Volume of distribution for water soluble meds70-75% children
Pediatric Pharmacology
● Use dose calculators to reduce risk of over or under dosing
● EHMR often have dose calculators
● pharmacy print outs to keep on paper charts
● Use of appropriate syringe size
● Label accuracy!
Inhalational Agents & Pediatrics
● Neonates very sensitive to hemodynamic effects of gases: caution for overdose
● Blood flow to vessel rich increase so rapid inhalation induction therefore rapid rise in alveolar concentration
Inhalational Agents & Pediatrics
● Neonates very sensitive to hemodynamic effects of gases: caution for overdose
● Blood flow to vessel rich increase so rapid inhalation induction therefore rapid rise in alveolar concentration
Pediatric Anesthesia Medications
● Ketamine: ● IV 1-2mg/kg ● IM 3- 5mg/kg ● IV Adjunct to propofol
for asthmatics ● Caution for peds with
cardiac issues/risks ● Dissociative effect/
caution if PTSD
Pediatric Anesthesia Medication
● Midazolam: ● IV 0.05-0.2mg/kg ● PO 0.3-0.7mg/kg
timing is essential for ideal anxiolytic effect
● Education for parents safety in preoperative holding
● Separation anxiety education
Pediatric Anesthesia Medications
● Propofol Induction Dosing may be higher
● Caution for Propofol infusion/TIVA cases for Propofol Infusion Syndrome! Cases as low as 90mcg/kg/minute as little as 8 hrs.
Propofol Infusion Syndrome
● Propofol Infusions may result in:
● Multisystem Organ Failure
● Metabolic Acidosis ● Hepatomegaly ● Rhabdomyolysis ● Death
Pediatric Anesthesia Medications● Opioids: ● Neonates very
sensitive to opioids ● Neonates have
increased bioavailibity ● Neonates opioids cross
blood brain barrier ● Neonate respiratory
center sensitive to opioids
Why? Cytochrome P 450 not
mature until 1 month Reduced Hepatic
Conjugation Reduced clearance of
Morphine Metabolites Concomitant Co
morbidities
Pediatric Anesthesia Medications
● Opioids: ● Children actually have
increased rates of flow thus rapid biotransformation & elimination
● Medication Labeling accuracy
● Dose Calculators in EHMR
Pediatric Anesthesia Pain Control
● Fentanyl IV ● Morphine IV caution
in neonates ● Tylenol Suppository ● Tylenol IV? (>2yrs) ● Local to field ● Regional ● Distraction & the
Digital Age
Pediatric Medications: Relaxants
● Faster Onset Time up to 50%! (30-60 sec)
● Succinylcholine (SUX) still only Depolarizing
● SUX: Hyperkalemia, Masseter Muscle Spasm, BRADY, Sinus Arrest! Must pretreat Atropine/Glyco
Pediatric Anthesis Medications● Non Depolarizing
Muscle Relaxants: ● Rocuronium: ● Ideal Induction Agent
rapid onset, can be used for Modified RSI
● Dosing 0.6 or 0.9mg/kg RSI
● Caution dosing may last up to 90 mins
Pediatric Muscle Relaxants
● Questions to ask: ● Do I really need to use
muscle relaxants, length of case, surgical skill, risk of recuraritization
● Can I combine Inhalational/IV technique to limit the need for NDMR?
Pediatric Anesthesia Medications
● Reversal Agents & Residual NDMR a significant concern!
● Monitor neuromuscular blockage Adductor Pollicis versus Orbicularis Oculi
Pediatric Anesthesia Medications
● Reversals: ● Neostigmine
0.03-0.07mg/kg must co administer anticholinergic! Vagal tonic pediatric physiology....separate syringes!
Pediatric Anesthesia Medications
● Reversal ● Anticholinergics: ● Atropine 0.01-0.02mg/
kg ● Glycopyrrolate
0.01mg/kg ● Pretreat & timing
Pediatric Anesthesia Medications
● Antiemetics: ● Zofran ● Reglan ● Promethazine ● Droperidol (black box) ● Multimodal technique:
use of nsaids, local, regional
Pediatric Anesthesia Adjuncts
● Locals: encourage use in surgical field
● Aspiration essential ● Remember max doses ● Lidocaine 3mg/kg ● Lidocaine w epi 7mg/
kg ● Marcaine 2-3mg/kg
Pediatric Preoperative Care
● NPO status? ● Keep peds hydrated ● NPO clears 2 hrs. ● NPO breast milk 4 hrs. ● NPO Formula 6 hrs. ● NPO Solids 8 hrs.
IV or Inhaled Induction IV discussion typically
around 8 or 9 yrs. Discuss with family/pt
Maturity of pt versus chronological age
IV access using Topical local/cream
Pediatric Preoperative Care
● Separation anxiety ● Educate family ● PO anxiolytics ● Distraction & Digital
Age ● Parental Presence?
Support, Assess Parents, Facility Protocols
Recent URI? ….more Febrile? Auscultate HR:
Murmur...innocent or symptomatic
Labs: type of procedure, childhood history: minimal labs, no labs
Pediatric Anesthesia
● URI? ● Infectious, Viral, Allergic,
Vasomotor Rhinitis ● Increased Risks must make
balanced decision risk versus benefit include family via education
Pediatric URI & General Anesthesia
● Risks: ● Increased risk of
wheezing up to 10X ● Increase risk of
Laryngospasm up to 5X
● Increased risks of hypoxemia, atelectasis, prolonged stay, ICU
Risks with URI 2-4 weeks time window for GA in pediatrics
Delay for non emergent cases to reduce risk of adverse event or outcome
Pediatric Anesthesia
● Environment: ● Preoperative limit
invasive interaction, allow child to remain in parents arm/hold
● Interactions age & developmental appropriate
Pediatric Anesthesia
● Environment ● OR: Limit noise, be
alert to visual fields, equipment, discussions
● Art of Distraction ● Language used
important: sleepy breeze versus put to sleep.
Pediatric Monitoring
● Pulse Oximeter!! ● HR typically too fast
or too slow ● BP cuff size
appropriate ● Neonates remember to
put pulse oximeter on right extremity or earlobe -Preductal
Pediatric Monitors
● Temperature! Accurate & early placement (MH)
● Invasive Lines available size appropriate
● Lab tubes size appropriate
Pediatric Anesthesia
● IV access challenging ● Often multiple sticks,
most experienced provider
● Vein illuminator ● Intraosseous
alternatively
Common Blades: Miller Wis Hipple Macintosh Phillips Video laryngoscopy
elective use
Pediatric Airway
● Endotracheal Cuffed versus Non cuffed
● Traditionally non cuffed ETT however in recently changing to cuffed ETT over 2 yrs.
● LMA used in variety of cases that traditionally ETT!
Pediatric Airway
● Neonate Uncuffed 2.5 to 4 ETT
● Uncuffed ETT: 4 + Age/4
● Cuffed ETT: 3 ½ + Age/4
● Depth is 3X ETT
Pediatric Anesthesia
● LMA pediatric sizes down to size 1 for neonate/infant
● Often forgotten as a bridge to ETT in problematic airway
● LMA placement gently to avoid damaging delicate tissues
Pediatric Ventilation● Volume ventilation
versus Pressure control modes?
● Volume Ventilation using circle systems newer machines 6-10cc/kg
● Pressure Control setting variable, conservative management
Pediatric Fluid Management
● Follow 4,2,1 Rule: ● First 10kg=4cc/kg/hr. ● Second 10kg=2cc/kg/
hr. ● >20kg=1cc/kg/hr. ● Replace 50% 1st hr. ● Replace 25% 2nd hr. ● Replace 25% 3rd hr.
Pediatric Fluid Management
● Minor Surgery add 2cc/kg
● Major Surgery add up to 10cc/kg
● Close calculation of EBL especially premies, neonates, infants
● Smaller folks have lower Allowable Loss!
Pediatric Blood Loss
● Estimated Blood Volume:
● Premies 95cc/kg ● Term Neonates 85cc/
kg ● Up to 1 yr. 80cc/kg Visualize, weight
sponges, labs
Pediatric Blood Loss● Initially replace with
NSS at 3X loss in cc ● What are the comorbid
conditions? ● PRBC replacement
usually starts @ 10cc/kg
● If EBL=1.5X blood volumes give FFP, platelets, possible cryo
FFP and platelets are 10cc/kg
Consider Coagulopathy Send advanced
coagulation studies: D dimer, bleeding time, fibrinogen levels
Pediatric Anesthesia Concerns
● Laryngospasm!! ● Involuntary spasm of
laryngeal musculature ● Stimulation of superior
laryngeal nerve ● Numerous causes:
light extubation, secretion on cords, recent URI, smoke exposure
Pediatric Anesthesia Concerns
● Laryngospasm: ● Positive Pressure
(CPAP) with mask seal ● SUX IV 0.1-0.5mg/kg ● SUX IM 2-4mg/kg ● Propofol 0.5-1mg/kg
(with CPAP)
Pediatric Anesthesia Concerns
● Post intubation stridor: ● Large ETT ● Repeated ETT
attempts ● Repeated ETT
movement ● Longer ENT
procedures/local Tonsils
Pediatric Anesthesia Concerns
● Post Intubation Stridor treatment:
● Preventative Dexamethasone
● Racemic EPI nebulized Treatment
● Cool mist in PACU ● Prolonged PACU/
admission
Pediatric Emergencies
● Pyloric Stenosis: ● male>female ● 4-6 weeks old ● Metabolic disarray: ● Hypochloremia,
hyponatremia, dehydration from vomiting
Correct metabolic issues prior to surgery
EMPTY stomach lateral, prone
RSI, ETT Careful lab monitoring
for lingering metabolic acidosis
Transfer?
Pediatric Foreign Body ● Foreign Body
Aspiration: ● Sudden onset ● Wheezing, respiratory
distress ● Supra versus
Subglottic location ● RSI, avoid further
advancing object, Magill's ready!
Rigid Bronchoscopy Multiple manipulations
of airway leading to possible trauma, iatrogenic injury, swelling of tissues, airway
Postoperative intubation, steroids
Pediatric Radiography of Foreign Body
Pediatric Foreign Body● Ingestion of object to
gastric pathway ● Avoid turning gastric
FB into airway FB ● Magill's ready ● Often multiple
attempts with Pediatric endoscopist
● Risk of injury upon removal
Malignant Hyperthermia● Children under 19 yrs.
account for 43-54% reported MH events
● 1:15,000 ● Triggering Agents: ● VOLATILES & SUX ● Genetic abnormality for
ryanodine receptor cause hypermetabolic state
Malignant Hyperthermia● Can Occur at
ANYTIME after exposure to trigger!
● MH Signs: Tachycardia, Hypercarbia, Hyperthermia, Cardiac disturbances, hemodynamic instability, rhabdomyolysis,
MH Signs: Myoglobinurinemia,
metabolic/respiratory acidosis, CK elevations, muscle rigidity
Atypical MH forms can be problematic to identify
Malignant Hyperthermia
● Treatment: ● Stop Offending Agents ● Call for Help: MH ● Hyperventilate with
“clean 100%” Oxygen ● Dantrolene 2.5mg/KG ● Revised Dantrolene
formulation
Contact MHAUS Support Cardiac
dysrhythmias (no calcium channel blockers)
NaHCO3 IV Active Cooling Invasive Monitors, ICU
Malignant Hyperthermia● Known History: ● Avoid triggering
agents ● Use TIVA & Nitrous as
needed. ● Cleanse machine based
on Manufacturer OEM guidelines
● Change circuit/sodasorb
Communication across all teams
Depending upon location/type of care facility...transfer to tertiary facility
MHAUS Hotline: 1-800-MH-HYPER
Malignant Hyperthermia
Pediatric Summary
● Pediatric Specialist versus Generalist
● Maintain Pediatric Anesthesia Proficiency to promote safety
● Use on site resources & cognitive aids for pediatrics
Pediatric Anesthesia Summary
● Smaller margin of safety with care of pediatric population
● What type of facility? ● Resources appropriate ● Transfer indicated? ● Ask for help in
pediatric cases if deskilled!
Summary
● Evolution of pediatric specialty centers & tertiary care facilities has lead to lower routine pediatric case volumes in community & non pediatric care centers
● Support for anesthesia providers knowledge base & skill sets!
Review & Reflect
Question: Pediatric anesthesia care
primary focuses on reduction in medication dosing due to smaller patient sizes? True of False.
Review & Reflect
● Pediatrics anesthesia care should include a comprehensive approach that reviews medical history, current clinical indicators/issues and psychosocial factors? True or False
Review & Reflect
● Malignant Hyperthermia considerations are less prominent in pediatric anesthesia care as compared to adult anesthesia care? True or False
Review & Reflect
● Malignant Hyperthermia considerations are less prominent in pediatric anesthesia care as compared to adult anesthesia care? True or False
Thanks for your Attention