Arterial vs. Venous blood in different lab measurements (CBC, Chemistry, Blood Gas)

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Description

Hi, thanks for all the important work you all do on MIMIC.

I'm trying to compare glucose levels in Arterial and Venous blood.
For this purpose, I saw that for part of the Blood Gas measurements the specimen type (Arterial blood vs. Venous blood) is available (following the CHARTTIME's trick in #488, #1161 and bg.sql script).

However, for the rest of the glucose measurements (for example ITEMID=50931 of the chemistry measurement) I couldn't find any information on the specimen type and I wonder if it is possible to assess whether the blood was obtained from Arterial or Venous blood.

I thought it might be beneficial to use the following heuristic - First, generate the central line and arterial line durations based on the queries mentioned in #371, and then 'Map' each glucose measurement to Venous vs. Arterial based on the existence of the central/arterial line (I saw that there are overlapping in part of the rows, so I'll exclude these measurements).

Your comment/advice would be greatly appreciated!

Many thanks in advance,

Dan

Start with bg.sql and the queries referenced in #371, and review the related discussion in #488 and #1161. Compare the available blood-gas specimen information with chemistry measurements such as ITEMID=50931 and document whether arterial or venous origin can be assessed reliably; completion should include clear guidance for researchers.