Extracting nutrition information from mimic_icu

[lkernl]

I'm interested in distinguishing between periods of time that ICU patients received any type of nutrition (e.g. enteral, parenteral, or oral intake) and when they didn't (to use as a covariate in further analysis). Would you have any recommendations as to how to determine this in the MIMIC-IV database?

Specific questions:

1. So far, I have extracted all itemids that contain 'Nutrition' in the category column in the d_items table in mimic_icu and filtered all rows with these itemids from the inputevents table. Does this seem like a good approach or am I missing something?
2. Does "PO Intake" (itemid 226452) reflect oral food intake (i.e. does it also count as nutrition) or is it more likely to be water intake?
3. Also, do you consider this information to reliably capture whether a patient received any type of nutrition at a specific moment in time? For example, how well is oral food intake recorded?

Thank you in advance for your help!