Paediatrics Flashcards
What is Poiseuille’s law?
As the diameter of a tube decreases, the resistance to flow increases exponentially. Which explains why children are more at risk from restrictions of the airway (Caroline, 2013).
How does a child’s head differ from and adults?
An infant’s head is 2/3rds the size it will be in adulthood. Head is 19% of BSA at birth reducing to 9% at around 15. This is important to consider with regard to heat loss and head injuries; the greater relative mass resulting in a higher incidence of head injuries. By school-age years the head is usually proportional to the body (Caroline,2013).
How does a child’s neck and airway differ from an adults?
The necks of children are relatively short and, critically, their airways are much narrower when compared with adult airways. As a result, it is much easier for the airway to become life-threateningly compromised by infection, inflammation or foreign bodies, or by the child’s relatively large tongue. In their first few months of life, infants are obligate nose breathers meaning that significant amounts of mucus in the nasal passages can cause serious respiratory distress. Their epiglottis is relatively flaccid and u-shaped which has implications when trying to view the vocal cords during intubation. In adults, the most restricted part of the airway occurs at the vocal cords but in children this occurs at the level of the cricoid cartilage (Caroline, 2013).
How does a child’s immune system and metabolism differ from an adults?
Anatomically and physiologically children, up to the age of 5, are still acquiring their own immune systems. Their defences are not yet fully mature making them more susceptible to infection. As the are still growing, they have a greater demand for oxygen, fluids and glucose. Their glucose reserves are very limited.
