...using a tourniquet for creating a bloodless field for surgical exploration, maybe?

Operative Techniques in Hand, Wrist, and Elbow Surgery
https://books.google.de/books?isbn=1496347579
Thomas R. Hunt - 2016 - ‎Medical
The surgeon should anticipate the need for tendon graft or transfer for ... Approach Wound exploration and débridement are performed in a bloodless field, with ...

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Note added at 1 day 1 hr (2019-04-25 11:11:35 GMT)
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I guess what it boils down to is: are we talking about medical procedures, or: what is a "medical procedure"? I personally would classify a negative or inconclusive investigation as a finding/outcome or condition (situation) rather than a medical procedure, but you may, of course, argue that an investigation is a procedure.
Same with your table: while the heading says "actes opératoires", the items are mostly what I would call "conditions" or intraoperative "findings", yet, you may read the items as "Repair/Treamtment of..." (implying what is explicitly stated in the last item, "Évacuation hématome"), which would make them "procedures".

My answer, and my reservations regarding "negative/inconclusive examination", are of course based on my own understanding of the term "medical procedure" which may or may not apply to your query.

Hello all,

I'm no expert, but this entry got me thinking. It's a tough one because French is rather abstract. So my suggestion comes from the meanings and nuances of 'blanc' that I could come up with with the help of a dictionary. I think here it might mean a something like a mock procedure or exam, something preliminary before another "real" procedure is performed.

Just a guess. Maybe it'll help