MindMap Gallery Pediatric anesthesia
Summary of pediatric anesthesia knowledge in clinical anesthesiology, including physiological characteristics of pediatric development, pharmacological characteristics of pediatric anesthesia, pre-anesthesia preparation, anesthesia management, post-anesthesia treatment, etc.
Edited at 2022-08-03 11:43:01El cáncer de pulmón es un tumor maligno que se origina en la mucosa bronquial o las glándulas de los pulmones. Es uno de los tumores malignos con mayor morbilidad y mortalidad y mayor amenaza para la salud y la vida humana.
La diabetes es una enfermedad crónica con hiperglucemia como signo principal. Es causada principalmente por una disminución en la secreción de insulina causada por una disfunción de las células de los islotes pancreáticos, o porque el cuerpo es insensible a la acción de la insulina (es decir, resistencia a la insulina), o ambas cosas. la glucosa en la sangre es ineficaz para ser utilizada y almacenada.
El sistema digestivo es uno de los nueve sistemas principales del cuerpo humano y es el principal responsable de la ingesta, digestión, absorción y excreción de los alimentos. Consta de dos partes principales: el tracto digestivo y las glándulas digestivas.
El cáncer de pulmón es un tumor maligno que se origina en la mucosa bronquial o las glándulas de los pulmones. Es uno de los tumores malignos con mayor morbilidad y mortalidad y mayor amenaza para la salud y la vida humana.
La diabetes es una enfermedad crónica con hiperglucemia como signo principal. Es causada principalmente por una disminución en la secreción de insulina causada por una disfunción de las células de los islotes pancreáticos, o porque el cuerpo es insensible a la acción de la insulina (es decir, resistencia a la insulina), o ambas cosas. la glucosa en la sangre es ineficaz para ser utilizada y almacenada.
El sistema digestivo es uno de los nueve sistemas principales del cuerpo humano y es el principal responsable de la ingesta, digestión, absorción y excreción de los alimentos. Consta de dos partes principales: el tracto digestivo y las glándulas digestivas.
Pediatric anesthesia
Physiological characteristics of children's development
respiratory system
cricoid cartilage and glottis
The narrowest point in infants is the cricoid cartilage
The glottis is narrowest after 6 years of age
Children are prone to functional airway closure at the end of expiration, resulting in a large difference in alveolar-arterial oxygen partial pressure.
The airway is relatively narrow and the airway resistance is large
The airway and chest wall have good compliance, but the surrounding tissues have poor support for them, making it difficult to maintain negative intrathoracic pressure.
Hypoxemia is prone to occur during perioperative period
The alveolar area is 1/3 of an adult’s
High basal metabolism
Limited respiratory function reserve
Inhalation anesthetics induce and wake up faster
Larger alveolar ventilation per minute
Functional residual capacity is similar to that of adults
Any increase in mechanical dead space will have a great impact on children's breathing
Low tidal volume
Physiological dead space accounts for 30% of tidal volume
Anything that causes increased respiratory effort can cause respiratory muscle fatigue, leading to apnea, carbon dioxide accumulation, and even respiratory failure.
Diaphragm and intercostal muscles are immature
Some children younger than 5 years old cannot switch to breathing through the mouth when their nasal cavities are blocked. Pay attention to keeping the nasal cavities open.
circulatory system
Establishment of fetal circulation and systemic circulation
fetal circulation
right to left shunt
foramen ovale
arterial catheter
Can cause severe hypoxemia
Common causes
premature birth
Infect
acidosis
hypoxia
carbon dioxide accumulation
low temperature
congenital heart malformation
systemic circulation establishment
Diversion channel closed
heart
Imperfect myocardial development and poor ventricular compliance
Sensitive to volume therapy
Inability to tolerate significant increases in afterload
Well tolerated increased heart rate
Bradycardia requires emergency treatment
Give oxygen
atropine
Low peripheral vascular resistance
Newborn 80/50mmhg
6 months 90/60mmhg
16 years old 120/70mmhg
Kidneys and fluid balance
renal insufficiency
Drugs excreted by the kidneys have extended half-life
Babies are prone to dehydration
There is more extracellular fluid than intracellular fluid
liver
Liver insufficiency
Poor drug degradation ability and long drug half-life
Newborns and premature infants
premature baby
Low liver glycogen reserves
Poor ability to process proteins
newborn
Low protein content in plasma
High concentrations of free drugs in plasma
gastrointestinal system
Stomach pH is alkaline at birth and becomes normal 2 days later
swallowing reflex
Not fully developed between 4 and 5 months
High incidence of gastroesophageal reflux in neonates
Developmental abnormalities of the gastrointestinal system
Can be found 1-2 days after birth
thermoregulation
The body temperature regulation mechanism of newborns is underdeveloped, there is less subcutaneous fat, the body surface area is relatively large, and heat is easily dissipated.
Enhance thermal insulation
electric blanket
Warmed infusion
Inhaled gas heating and humidification
Babies younger than 3 months old cannot produce heat through the chill response
Mainly relies on brown fat to produce heat, and this metabolism is controlled by sympathetic nerves
General anesthesia can affect brown fat metabolism, leading to lower body temperature during surgery
Lowering body temperature can cause the depth of general anesthesia to deepen easily
Respiratory and circulatory depression
Prolonged drug metabolism
Inadequate ventilation during surgery
Reflux and aspiration
Central Nervous System
pain is present
The endings that conduct pain sensation in newborns already exist
Physiological and biochemical responses to painful stimuli
Highly permeable blood-brain barrier
Opioid tapering
Bilirubin also easily enters the blood-brain barrier
Increased minimum alveolar effective concentration of inhaled anesthetics in children
High metabolic rate
The central nervous system is relatively mature
Characteristics of Pediatric Anesthetic Pharmacology
Overview
Water-soluble drugs have a large distribution volume and require a larger dose to achieve the required blood concentration (such as succinylcholine)
Since newborns and infants have low fat content, drugs that rely on fat redistribution to terminate their effects have a longer effect time (sodium thiopental)
Likewise, drugs that are redistributed to muscles have a longer duration of action (fentanyl)
The blood-brain barrier is not fully developed at birth
Drug concentration in the brain is higher than in adults
Immature liver and kidney function and low protein binding rate in infants and young children can lead to delayed drug metabolism.
inhalation anesthetic
The therapeutic range between the anesthetic effect of inhaled anesthetic drugs and respiratory and circulatory depression is small, and close monitoring must be performed during the operation.
nitrous oxide
Congenital diaphragmatic hernia or umbilical hernia
necrotizing enteritis
Enflurane
epilepsy
Isoflurane
Obvious pungent odor
Sevoflurane
Commonly used
Desflurane
Strongly irritating to the respiratory tract
intravenous anesthetic
Propofol
Doses greater than adults
Ketamine
etomidate
use less
Depth of anesthesia is difficult to control
Large infusion volume
midazolam
Commonly used
opioid analgesics
morphine
Avoid use under 1 year of age
Children have a low tolerance for fibrin
High blood-brain barrier permeability in children
Can easily cause increased blood drug concentration
Morphine has low protein binding in neonates
Significant ventilation depression
prone to constipation
Contraction of gastrointestinal smooth muscles and sphincters
Increases biliary and bronchial smooth muscle tension
Fentanyl
Most commonly used in infants and young children
Watch out for bradycardia
Alfentanil
Pay attention to prevent vomiting and respiratory depression
sufentanil
Mainly used for pediatric cardiac surgery
remifentanil
Watch for bradycardia, apnea, chest wall stiffness and vomiting
Muscle relaxants
Succinylcholine
Large dosage
Intravenous 1.5-2mg/kg
Watch out for bradycardia
pancuronium bromide
Long lasting
0.1mg/kg
side effects, tachycardia
atracurium
Can induce histamine release
asthma
0.3-0.5mg/kg
Homeopathic Atracurium
0.15-0.2mg/kg
Vecuronium bromide
0.1mg/kg
No histamine release, no cardiovascular side effects
Rocuronium
0.6mg/kg
Rapid onset of action
Cardiovascular side effects and histamine release are rare
Preparation before anesthesia
Preoperative visit
Explain and reduce fear
Medical history
allergy
congenital malformation
bleeding tendency
Difficulty breathing or hypoxic episodes
Medication and surgery
Physical examination
loose teeth
Are tonsils serious?
Cardiopulmonary function
Fever and dehydration
Feeling good
Auxiliary inspection
anemia
Hypoglycemia
Hypokalemia
Hypocalcemia
Coagulopathy
acute infection
Fasting before surgery
<6 months/6 months to 36 months/>36 months
4-2/6-3/8-3
solid food, milk-sugar fruit juice
Pre-anesthetic medication
No sedatives are required for children under 6 months of age
Most children are given adequate amounts of anticholinergic drugs before surgery
anesthesia management
induction of anesthesia
induction method
Inhaled sevoflurane
Cooperative children
After entering the room, use a mask to inhale oxygen 1-2L/kg with sevoflurane
Gradually increase sevoflurane concentration (up to 8%)
Until the eyelash reflex of the child disappears, the concentration is controlled below 4%.
Uncooperative children
Start and inhale high-concentration anesthetic 8% oxygen 6-8L/kg
Once consciousness disappears, the intravenous access can be opened and induction completed.
Precautions
If you hold your breath
Determine whether there is airway obstruction and laryngospasm
If laryngospasm occurs, intravenous muscle relaxants
Management of children with full stomach
Treatment principles are similar to adults
Oxygen saturation drops rapidly during rapid induction in children, and sufficient oxygen and nitrogen removal are required before induction.
To prevent an increase in intragastric pressure, it is best to use non-depolarizing muscle relaxants
Management of difficult airway
Children with epiglottitis, tracheobronchitis, and foreign bodies in the larynx
Inspiratory stridor and crying can cause airway collapse, thereby aggravating airway obstruction and leading to hypoxia and respiratory failure.
Sevoflurane is commonly used for induction, and venipuncture is performed after the child falls asleep.
During induction, if stridor worsens or laryngospasm occurs, appropriate pressurization ventilation should be performed
Choose an uncuffed catheter and reduce the inner diameter of the catheter accordingly
Complete airway obstruction, difficulty in mask ventilation, or difficulty in endotracheal intubation
emergency tracheotomy
Endotracheal tube selection
Selection of endotracheal tubes for children over 1 year old
Selection for children under 1 year old
premature birth
Full term
1-6 months
6 months-12 months
Pediatric ventilation device
Pediatric regional anesthesia
Monitoring during anesthesia
stethoscope
The simplest and most valuable
electrocardiogram
blood pressure
cuff
Upper arm length 1/2
Invasive artery
Only used for major surgeries or surgeries where heavy bleeding is expected
body temperature
Pulse oxygen
End tidal carbon dioxide
urine output
Perioperative fluid management
Preoperative loss
Fasting time*maintenance volume per hour
4-2-1
1/2 is replenished in the 1st hour, 1/4 is replenished in the 2nd and 3rd hours
intraoperative loss
Anesthesia related
vasodilation
loss of airway
Surgery related
Superficial surgery 2ml/kg
Medium surgery 4ml/kg
Major surgery 6ml/kg
Major intra-abdominal surgery can reach up to 10ml/kg
Is it necessary to supplement hemoglobin during surgery?
Consider the ratio of blood loss to total blood volume
Calculate the maximum allowable blood loss MABL
Estimated blood volume*(initial hematocrit-tolerable Hct)/initial Hct
Tolerable Hct
25-30%
Within 3 months
35%
Blood loss <1/3MABL
Balance solution (1:3)
1/3-1MABL
Colloid (1:1)
>1MABL
blood transfusion
Clotting factors and others
fresh frozen plasma
platelets
Post-anesthesia treatment
hypoxia
main reason
upper respiratory tract obstruction
lingual suffix
laryngospasm
hypoventilation
Pain restricts breathing
pain
Evaluate
visual analog scale
Physiological and behavioral parameters
deal with
Patient/nurse controlled analgesia
Opioids
peripheral nerve block
nonsteroidal drugs