Paediatrics Flashcards
What 4 main anatomical reasons result in children being more likely to suffer from respiratory issues
- Narrower airway
- Shorter airway
- Tonsils disproportionately large
- Epiglottis disproportionately large
Why do children have less surface area for gas exchange?
They have fewer alveoli than adults
Why does the larynx sit higher and further forward in children?
Because they have a ‘shorter neck’
Children are obligate ……….. breathers?
Nose
What structure is primarily drives breathing in children?
The diaphragm
Why are children’s chest walls easily collapsible?
Cartilaginous skeleton has not fully ossified
What can children’s immature neurological reflexes for blood gas lead to more easily?
Acidosis
Why do children consume more energy at rest?
Through the work of breathing
Higher BMR
How many times more oxygen do children consume compared to adults?
2x
What can be triggered by laryngeal stimulation in children?
The aponeic response
What four main things can activate the aponeic response?
- Foreign bodies
- Airway adjuncts
- Infection
- Irritation
How are childrens ribs orientated differently?
They are more horizontal - restricting upward movement
What two cavities does the diaphragm separate?
The abdominal and thoracic cavities
Up to what age approximately are children diaphragmatic breathers?
~5years old
Why does the paediatric diaphragm have a reduced range of movement?
It is anatomically flatter than an adults
What 2 other properties of the paediatric diaphragm lead to issues?
- Lack of type 1 muscle fibres (resistance to fatigue and fast reaction)
- Abdominal organs cause resistance on inspiration
Why do chest retractions occur in respiratory distress?
A reduction of pressure in the chest and a less self supporting rib cage
What two locations will paradoxical breathing primarily be seen?
- Substernally
2. Below the scapula
What happens to respiratory rate as age increases?
It decreases
At birth how much of the heart is made up of myocardium?
~30%
What two properties result from there being less myocardium?
- Less mass
2. Less compliance
Why do the myocardium cells have less compliance in children?
There are fewer mitochondria in paediatric myocardium compared to adults
Why do children have the capacity for less stroke volume?
Anatomically smaller hearts that are less pliable
Is cardiac output higher in children than in adults?
Yes
What is the equation for cardiac output?
HR x SV
Why is heart rate in children less sensitive to adrenaline and noradrenaline?
Due to the lack of receptors
Are heart murmurs common in children?
Yes (innocent murmurs)
Why are children at an increased risk of dehydration?
Due to their volume:surface area ratio their loose more fluid
Tachypnoeic
List some signs and symptoms of dehydration in children
- Lack of wet nappies
- Irritable
- Sunken eyes
- Tachycardia
- Lethargy
- Dry membranes
- Skin turgour (lack of)
- Low B.P.
What happens to intersitial fluid distribution as a child ages?
It decreases
What does increased extracellular fluid in children increase the risk of?
Dehydration
How does a childs anatomically large liver impact respiratory function?
Causes pressure on the Diaphragm
Why are children more susceptible to hypoglycemia?
Liver enzymes are immature
Store less glycogen
Limited muscle (less AA stores)
What are foetal bones layed down as initially in development?
Cartilage
Why must one be cautious when gaining IO access in paeds?
The presence of growth plates in long bones
What is the preferred IO site in paediatrics?
Proximal tibia
Childrens nervous systems are anatomically complete at birth however what does not occur fully until age 7?
Full nerve myelination
Why do paediatric patients have issues with heat retention?
Their homeostatic mechanisms and reflexes are immature
What happens to the number of synapses at a young age?
Increases rapidly as new connections are formed
What is synaptic pruning?
The elimination of of excess synapses to increase the efficiency of the neural network?
By what % does the number of synapses reduce by between the ages of 2-10 years?
50%
How are synaptic connections strengthened in children?
Synapses that are frequently used such as those with sensory, cognitive and motor functions
Which synaptic connections are ‘pruned’?
Those connections that have been weakly reinforced and no longer are needed for normal functioning
Young children are generally able to recover better from brain injury. Why is this?
Extra/redundant synaptic connections that have not been pruned can be used in place of damaged pathways to preserve certain functions
Why is Intramuscular injection best avoided in children?
Due to their low muscle mass
What is the preferred IM injection site in children?
Anterolateral thigh (vastus lateralis)
Children have less fat stores than adults. How does this affect doses given?
Less drug is taken up into fat thus the dose of fat soluble drugs given is reduced
How does a childs increased ECF volume affect drug doses?
Increased ECF leads to drug dilution
Therefore and increased dose/kg is needed
Children metabolise drugs via the liver like adults however why are they at increased overdose risk?
The immaturity of the liver and its enzymes
Higher BMR –> Increased dose/kg
What can children have impaired drug excretion?
Immature renal function (increased half life - metabolism poor)
Why may the use of glucagon be ineffective when treating a hypoglycaemic paediatric patient?
They store less glycogen… therefore have less to be released
