Outline the effects of critical illness on drug pharmacokinetics, including examples.
The effects of critical illness on the physiological factors that influence drug pharmacokinetics was used to analyse the candidates understanding of this core pharmacological principle. Better responses were able to identify the key elements perturbed by critical illness as well as outlining outline the potential cause and effect on the specific PK aspect being discussed. Stronger answers also included specific drug examples. The failure to utilise a structure (absorption, distribution, metabolism, and elimination) with very superficial detail and limited examples limited marks and was common in poorly scoring answers.
This question is identical to Question 13 from the first paper of 2013. The college comments in 2013 were a bit less vague. Apart from examples and ADME structure, it appears they were also looking for a direction of change, which they did not mention this time.
Absorption
Distribution
Metabolism
Elimination
Boucher, Bradley A., G. Christopher Wood, and Joseph M. Swanson. "Pharmacokinetic changes in critical illness." Critical care clinics 22.2 (2006): 255-271.
Roberts, Derek J., and Richard I. Hall. "Drug absorption, distribution, metabolism and excretion considerations in critically ill adults." Expert opinion on drug metabolism & toxicology 9.9 (2013): 1067-1084.
Smith, Brian S., et al. "Introduction to drug pharmacokinetics in the critically ill patient." CHEST Journal 141.5 (2012): 1327-1336.