With respect to the use of Parenteral Nutrition (PN) in critically ill patients, briefly discuss using the following headings in your answer:
a) Supplemental PN – rationale, timing, along with your evidence-based approach to supplemental PN. (60% marks)
b) Principles of prescription of Total Parenteral Nutrition (TPN) for a critically ill ICU patient. (40% marks)
This question was poorly answered with a common lack of details in specific areas, which were a lack of evidence, or evidence that was incorrectly cited / interpreted. There commonly no clear approach provided about the candidates own practice. Furthermore, in part b) of the question, there was minimal details about required vascular access and ongoing monitoring.
If one were still surprised by such things, one might retort that vascular access and monitoring are not a part of the TPN prescription, as (for example) they are usually not charted along with the TPN constituents on the fluid/medication chart. The questions reads like a repeat of Question 7 from the first paper of 2015, except this time the candidates were also expected to answer something that wasn't asked. An answer which ticks all the boxes for the examiners would resemble the following:
a) Supplemental PN
Rationale for supplemental PN
Timing of supplemental PN
Evidence to support this practice
b) TPN prescription:
The monitoring guidance comes from BAPEN (Parenteral Nutrition Monitoring) which is in turn based mainly on ESPEN and NICE guidelines, but it may be a bit dated (2016)
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