Discuss the determinants of intracranial pressure (80% of marks). Outline how it can
be measured (20% of marks).
It was expected answers would include an explanation of the Monro-Kellie Doctrine. Many
candidates gave insufficient details of compensatory mechanisms especially regarding
decreased total cerebral blood volume (primarily venous) in response to increased intracranial
Most candidates had all the information but had difficulty synthesising the information to write a
cohesive answer. Factors affecting ICP could be divided into factors affecting CBV, factors
affecting CSF and factors affecting brain tissue. Under factors affecting CBV the effect of blood
gases, autoregulation, temperature, metabolism, drugs and venous obstruction could have been detailed.