Describe the factors that affect airway resistance.
Important factors to be discussed in this answer were anatomical site, laminar versus
turbulent flow, airway calibre and factors that affect it such as oedema and sympathetic tone.
The effect of lung volume on airway resistance is usefully described in a diagram.
The differences in infants earned extra marks
Syllabus B1d, 2h
Reference: Nunn 6th edition p39-47.